Ajouter README.md

meta
fix
2025-05-21 10:38:18 +02:00 · 2025-05-09 11:50:32 +02:00 · 2025-05-09 11:13:29 +02:00 · 2025-05-06 18:20:08 +02:00 · 2025-05-05 23:18:26 +02:00 · 2024-05-12 11:17:03 +02:00
22 changed files with 1176 additions and 752 deletions
--- a/400.php
+++ b/400.php
@ -0,0 +1,27 @@
+<?php http_response_code(400); ?>
+<!DOCTYPE html>
+<html lang='fr'>
+    <head>
+        <?php require("head.php"); ?>
+        <title>Requête incorrecte</title>
+    </head>
+    <body>
+        <nav class="navbar mb-4">
+            <h1 class="display-4 text-center m-auto">Sudoku</h1>
+        </nav>
+        <main class="container my-4">
+            <header>
+                <h1 class="mb-4">Requête incorrecte</h1>
+            </header>
+            L'adresse URL doit être de la forme :<br/>
+            <?=$dirUrl?>/?<em>grille</em><br/>
+            <em>grille</em> étant une suite de 81 caractères représentant la grille de gauche à droite puis de haut en bas, soit :
+            <ul>
+                <li>un chiffre entre 1 et 9 pour les cases connues</li>
+                <li>un tiret (-) pour les case vides</li>
+            </ul>
+            Exemple :<br/>
+            <a href='<?=$newGridUrl?>'><?=$newGridUrl?></a>
+        </main>
+    </body>
+</html>
--- a/README.md
+++ b/README.md
@ -0,0 +1,5 @@
+# Sudoku
+
+Web sudoku assistant
+
+![screenshot](https://git.malingrey.fr/adrien/sudoku/raw/branch/master/thumbnail.png)
--- a/app.js
+++ b/app.js
@ -1,295 +0,0 @@
-const VALUES = "123456789"
-const SUGESTION_DELAY = 60000 //ms
-
-let boxes = []
-let rows = Array.from(Array(9), x => [])
-let columns = Array.from(Array(9), x => [])
-let regions = Array.from(Array(9), x => [])
-let suggestionTimer= null
-let highlightedValue = ""
-let history = []
-let accessKeyModifiers = "AccessKey+"
-let penStyle = "ink-pen"
-
-window.onload = function() {
-    let rowId = 0
-    for (let row of grid.getElementsByTagName('tr')) {
-        let columnId = 0
-        for (let box of row.getElementsByTagName('input')) {
-            let regionId = rowId - rowId%3 + Math.floor(columnId/3)
-            if (!box.disabled) {
-                box.onfocus = onfocus
-                box.oninput = oninput
-                box.onblur = onblur
-            }
-            box.oncontextmenu = oncontextmenu
-            box.rowId = rowId
-            box.columnId = columnId
-            box.regionId = regionId
-            boxes.push(box)
-            rows[rowId].push(box)
-            columns[columnId].push(box)
-            regions[regionId].push(box)
-            columnId++
-        }
-        rowId++
-    }
-    boxes.forEach(box => {
-        box.neighbourhood = new Set(rows[box.rowId].concat(columns[box.columnId]).concat(regions[box.regionId]))
-        box.neighbourhood.delete(box)
-        box.neighbourhood = Array.from(box.neighbourhood)
-        searchCandidatesOf(box)
-    })
-    
-    enableButtons()
-    highlightAndTab()
-    
-    if (/Win/.test(navigator.platform) || /Linux/.test(navigator.platform)) accessKeyModifiers = "Alt+Maj+"
-    else if (/Mac/.test(navigator.platform)) accessKeyModifiers = "⌃⌥"
-    for(node of document.querySelectorAll("*[accesskey]")) {
-        node.title += " [" + (node.accessKeyLabel || accessKeyModifiers + node.accessKey) + "]"
-    }
-    
-    document.onclick = function (event) {
-        contextMenu.style.display = "none"
-    }
-    suggestionTimer = setTimeout(showSuggestion, 30000)
-}
-
-function searchCandidatesOf(box) {
-    box.candidates = new Set(VALUES)
-    box.neighbourhood.forEach(neighbour => box.candidates.delete(neighbour.value))
-    if (!box.disabled)
-        box.title = box.candidates.size + (box.candidates.size <= 1 ? " possibilité [Clic-droit]" : " possibilités [Clic-droit]")
-}
-
-function onfocus() {
-    if (penStyle == "pencil" && this.value == "") {
-        this.value = this.placeholder
-        this.placeholder = ""
-        this.classList.add("pencil")
-    } else {
-        this.select()
-    }
-}
-
-function oninput() {
-    history.push({box: this, value: this.previousValue, placeholder: this.previousPlaceholder})
-    undoButton.disabled = false
-    if (penStyle != "pencil") {
-        refresh(this)
-    }
-}
-
-function undo() {
-    if (history.length) {
-        previousState = history.pop()
-        previousState.box.value = previousState.value
-        previousState.box.placeholder = previousState.placeholder
-        refresh(previousState.box)
-        if (history.length < 1) undoButton.disabled = true
-    }
-}
-
-function refresh(box) {
-    box.neighbourhood.concat([box]).forEach(neighbour => {
-        searchCandidatesOf(neighbour)
-        neighbour.setCustomValidity("")
-        neighbour.required = false
-    })
-    
-    enableButtons()
-    highlightAndTab()
-    
-    for (neighbour1 of box.neighbourhood) {
-        if (neighbour1.value.length == 1) {
-            for (area of [
-                {name: "région", neighbours: regions[neighbour1.regionId]},
-                {name: "ligne", neighbours: rows[neighbour1.rowId]},
-                {name: "colonne", neighbours: columns[neighbour1.columnId]},
-            ])
-                for (neighbour2 of area.neighbours)
-                    if (neighbour2 != neighbour1 && neighbour2.value == neighbour1.value) {
-                        for (neighbour of [neighbour1, neighbour2]) {
-                            neighbour.setCustomValidity(`Il y a un autre ${neighbour.value} dans cette ${area.name}.`)
-                        }
-                    }
-        } else {
-            if (neighbour1.candidates.size == 0) {
-                neighbour1.setCustomValidity("Aucun chiffre possible !")
-                neighbour1.required = true
-            }
-        }
-    }
-            
-    if (box.form.checkValidity()) { // Correct grid
-        if (boxes.filter(box => box.value == "").length == 0) {
-            alert(`Bravo ! Vous avez résolu la grille.`)
-        } else {
-            if (suggestionTimer) clearTimeout(suggestionTimer)
-            suggestionTimer = setTimeout(showSuggestion, SUGESTION_DELAY)
-        }
-    } else { // Errors on grid
-        box.form.reportValidity()
-        box.select()
-    }
-}
-
-function onblur() {
-    if (this.classList.contains("pencil")) {
-        this.placeholder = this.value
-        this.value = ""
-        this.classList.remove("pencil")
-    }
-    this.previousValue = this.value
-    this.previousPlaceholder = this.placeholder
-}
-
-function enableButtons() {
-    for (button of buttons.getElementsByTagName("button")) {
-        if (boxes.filter(box => box.value == "").some(box => box.candidates.has(button.textContent))) {
-            button.disabled = false
-        } else {
-            button.disabled = true
-            if (highlightedValue == button.textContent) highlightedValue = ""
-        }
-    }
-}
-
-function highlight(value) {
-    if (value == highlightedValue) {
-        highlightedValue = ""
-    } else {
-        highlightedValue = value
-    }
-    for (button of buttons.getElementsByTagName("button")) {
-        if (button.textContent == highlightedValue) button.classList.add("pressed")
-        else button.classList.remove("pressed")
-    }
-    highlightAndTab()
-    boxes.filter(box => box.value == "" && box.tabIndex == 0)[0].focus()
-}
-
-function highlightAndTab() {
-    if (highlightedValue) {
-        boxes.forEach(box => {
-            if (box.value == highlightedValue) {
-                box.classList.add("same-value")
-                box.tabIndex = -1
-            }
-            else { 
-                box.classList.remove("same-value")
-                if (box.candidates.has(highlightedValue)) {
-                    box.classList.remove("forbidden-value")
-                    box.tabIndex = 0
-                } else {
-                    box.classList.add("forbidden-value")
-                    box.tabIndex = -1
-                }
-            }
-        })
-    } else {
-        boxes.forEach(box => {
-            box.classList.remove("same-value", "forbidden-value")
-            box.tabIndex = 0
-        })
-    }
-}
-
-function shuffle(iterable) {
-    array = Array.from(iterable)
-    if (array.length > 1) {
-        let i, j, tmp
-        for (i = array.length - 1; i > 0; i--) {
-            j = Math.floor(Math.random() * (i+1))
-            tmp = array[i]
-            array[i] = array[j]
-            array[j] = tmp
-        }
-    } 
-    return array
-}
-
-easyFirst = (box1, box2) => box1.candidates.size - box2.candidates.size
-
-function showSuggestion() {
-    const emptyBoxes = boxes.filter(box => box.value == "" && box.candidates.size == 1)
-    if (emptyBoxes.length) {
-        shuffle(emptyBoxes)[0].placeholder = "💡"
-    } else {
-        clearTimeout(suggestionTimer)
-        suggestionTimer = null
-    }
-}
-
-function oncontextmenu(event) {
-    event.preventDefault()
-    while (contextMenu.firstChild) contextMenu.firstChild.remove()
-    const box = event.target
-    if (box.candidates.size) {
-        candidatesArray = Array.from(box.candidates).sort().forEach(candidate => {
-            li = document.createElement("li")
-            li.innerText = candidate
-            li.onclick = function (event) {
-                contextMenu.style.display = "none"
-                box.value = event.target.innerText
-                oninput.apply(box)
-            }
-            contextMenu.appendChild(li)
-        })
-    } else {
-        li = document.createElement("li")
-        li.innerText = "Aucun chiffre possible"
-        li.classList.add("error")
-        contextMenu.appendChild(li)
-    }
-    contextMenu.style.left = `${event.pageX}px`
-    contextMenu.style.top = `${event.pageY}px`
-    contextMenu.style.display = "block"
-    return false
-}
-
-function useInkPen() {
-    inkPenButton.classList.add("pressed")
-    pencilButton.classList.remove("pressed")
-    penStyle = "ink-pen"
-}
-
-function usePencil() {
-    pencilButton.classList.add("pressed")
-    inkPenButton.classList.remove("pressed")
-    penStyle = "pencil"
-}
-
-function erase(someBoxes) {
-    for (box of someBoxes) {
-        box.value = ""
-        box.placeholder = ""
-        searchCandidatesOf(box)
-        refresh(box)
-    }
-    enableButtons()
-    highlightAndTab()
-}
-
-function erasePencil() {
-    if (confirm("Effacer les chiffres écrits au crayon ?")) {
-        boxes.filter(box => !box.disabled).forEach(box => {
-            box.placeholder = ""
-        })
-    }
-}
-
-function eraseAll() {
-    if (confirm("Effacer tous les chiffres écrits au crayon et au stylo ?")) {
-        boxes.filter(box => !box.disabled).forEach(box => {
-            box.value = ""
-            box.placeholder = ""
-            box.setCustomValidity("")
-            box.required = false
-        })
-        boxes.forEach(searchCandidatesOf)
-        enableButtons()
-        highlightAndTab()
-    }
-}
--- a/classes.php
+++ b/classes.php
@ -1,5 +1,7 @@
 <?php
-    const UNKNOWN = ".";
+    const UNKNOWN = "-";
+
+    $validGrids = array();

    function isKnown($box) {
        return $box->value != UNKNOWN;
@ -24,16 +26,20 @@
    }
        
    class Box {
-        public $values = array("1", "2", "3", "4", "5", "6", "7", "8", "9");
+        public $values = array('1', '2', '3', '4', '5', '6', '7', '8', '9');
+        public $value = UNKNOWN; 
+        public $rowId;
+        public $columnId;
+        public $regionId;
+        public $candidates;
+        public $candidateRemoved = array();
+        public $neighbourhood = array();

        function __construct($rowId, $columnId, $regionId) {
-            $this->value = UNKNOWN;
            $this->rowId = $rowId;
            $this->columnId = $columnId;
            $this->regionId = $regionId;
            $this->candidates = $this->values;
-            $this->candidateRemoved = array();
-            $this->neighbourhood = array();
        }
        
        function searchCandidates() {
@ -46,14 +52,19 @@
    }
    
    class Grid {
-        function __construct() {
-            $this->boxes = array();
+
+        private $boxes = array();
+        private $rows;
+        private $columns;
+        private $regions;
+
+        function __construct($gridStr="") {
            $this->rows = array_fill(0, 9, array());
            $this->columns = array_fill(0, 9, array());
            $this->regions = array_fill(0, 9, array());
            for ($regionRowId = 0; $regionRowId < 3; $regionRowId++) {
-                for($regionColumnId = 0; $regionColumnId < 3; $regionColumnId++) {
-                    for ($rowId = 3*$regionRowId; $rowId < 3*($regionRowId+1); $rowId++) {
+                for ($rowId = 3*$regionRowId; $rowId < 3*($regionRowId+1); $rowId++) {
+                    for($regionColumnId = 0; $regionColumnId < 3; $regionColumnId++) {
                        for ($columnId = 3*$regionColumnId; $columnId < 3*($regionColumnId+1); $columnId++) {
                            $regionId = 3*$regionRowId + $regionColumnId;
                            $box = new Box($rowId, $columnId, $regionId);
@ -72,49 +83,89 @@
                    if ($box != $neighbour && !in_array($neighbour, $box->neighbourhood))
                        $box->neighbourhood[] = $neighbour;
            }
+
+            if ($gridStr) {
+                $this->import($gridStr);
+            } else {
+                $this->generate();
+            }
+        }
+
+        function import($gridStr) {
+            foreach ($this->boxes as $i => $box) { 
+                $box->value = $gridStr[$i];
+            }
+            forEach($this->boxes as $box) {
+                forEach($box->neighbourhood as $neighbour)
+                    array_unset_value($box->value, $neighbour->candidates);
+            }
        }

        function generate() {
            // Init with a shuffle row
            $values = array("1", "2", "3", "4", "5", "6", "7", "8", "9");
            shuffle($values);
-            forEach($values as $columnId => $value) {
-                $box = $this->rows[0][$columnId];
-                $box->value = $value;
+            forEach($this->rows[0] as $columnId => $box) {
+                $box->value = $values[$columnId];
                forEach($box->neighbourhood as $neighbour)
                    array_unset_value($box->value, $neighbour->candidates);
            }
            // Fill grid
            $this->solutionsGenerator(true)->current();
            
-            // Remove clues while there is still a unique solution
-            shuffle($this->boxes);
-            $nbClues = count($this->boxes);
-            foreach($this->boxes as $testBox) {
-                $testBoxes = array($testBox);
-                if ($nbClues >=30)
-                    $testBoxes[] = $this->rows[8-$testBox->rowId][8-$testBox->columnId];
-                if ($nbClues >=61) {
-                    $testBoxes[] = $this->rows[8-$testBox->rowId][$testBox->columnId];
-                    $testBoxes[] = $this->rows[$testBox->rowId][8-$testBox->columnId];
+            // Group boxes with their groupedSymetricals
+            $groupedSymetricals = array(array($this->rows[4][4]));
+            for ($rowId = 0; $rowId <= 3; $rowId++) {
+                for ($columnId = 0; $columnId <= 3; $columnId++) {
+                    $groupedSymetricals[] = array(
+                        $this->rows[$rowId][$columnId],
+                        $this->rows[8-$rowId][8-$columnId],
+                        $this->rows[8-$rowId][$columnId],
+                        $this->rows[$rowId][8-$columnId]
+                    );
                }
-                $testBoxes = array_filter($testBoxes, "isKnown");
-                $erasedValues = array();
-                forEach($testBoxes as $testBox) {
-                    $erasedValues[] = $testBox->value;
+                $groupedSymetricals[] = array(
+                    $this->rows[$rowId][4],
+                    $this->rows[8-$rowId][4]
+                );
+            }
+            for ($columnId = 0; $columnId <= 3; $columnId++) {
+                $groupedSymetricals[] = array(
+                    $this->rows[4][$columnId],
+                    $this->rows[4][8-$columnId]
+                );
+            }
+
+            // Remove clues randomly and their groupedSymetricals while there is still a unique solution
+            shuffle($groupedSymetricals);
+            foreach($groupedSymetricals as $symetricals) {
+                shuffle($symetricals);
+                foreach ($symetricals as $testBox) {
+                    $erasedValue = $testBox->value;
                    $testBox->value = UNKNOWN;
                    forEach($testBox->neighbourhood as $neighbour)
                        $neighbour->searchCandidates();
-                }
-                if ($this->isValid()) {
-                    $nbClues -= count($testBoxes);
-                } else {
-                    forEach($testBoxes as $i => $testBox) {
-                        $testBox->value = $erasedValues[$i];
+                    if (!$this->isValid()) {
+                        $testBox->value = $erasedValue;
                        forEach($testBox->neighbourhood as $neighbour) array_unset_value($testBox->value, $neighbour->candidates);
                    }
                }
            }
+            $validGrids[] = $this->toString();
+        }
+
+        function containsDuplicates() {
+            foreach(array_merge($this->rows, $this->columns, $this->regions) as $area) {
+                $knownBoxes = array_filter($area, "isKnown");
+                foreach($knownBoxes as $box1) {
+                    foreach($knownBoxes as $box2) {
+                        if (($box1 != $box2) && ($box1->value == $box2->value)) {
+                            return true;
+                        }
+                    }
+                }
+            }
+            return false;
        }

        function countSolutions($max=2) {
@ -122,10 +173,13 @@
            $solutionsWithoutDuplicates = array();
            $nbSolutions = 0;
            foreach($solutions as $solution) {
-                $solutionsWithoutDuplicates[$solution] = true;
-                $nbSolutions = count($solutionsWithoutDuplicates);
-                if ($nbSolutions >= $max) {
-                    $solutions->send(true);
+                if (!in_array($solution, $solutionsWithoutDuplicates)) {
+                    $solutionsWithoutDuplicates[] = $solution;
+                    $nbSolutions ++;
+                    if ($nbSolutions >= $max) {
+                        $solutions->send(true);
+                        break;
+                    }
                }
            }
            return $nbSolutions;
@ -141,20 +195,12 @@
                if ($randomized) shuffle($emptyBoxes);
                usort($emptyBoxes, "easyFirst");
                $testBox = $emptyBoxes[0];
-                $nbTries = 0;
                if ($randomized) shuffle($testBox->candidates);
                $stop = null;
                foreach($testBox->candidates as $testBox->value) {
-                    $correctGrid = true;
                    foreach(array_filter($testBox->neighbourhood, "isUnknown") as $neighbour)
                        $neighbour->candidateRemoved[] = array_unset_value($testBox->value, $neighbour->candidates);
-                    foreach(array_filter($testBox->neighbourhood, "isUnknown") as $neighbour) {
-                        if (count($neighbour->candidates) == 0) {
-                            $correctGrid = false;
-                            break;
-                        }
-                    }
-                    if ($correctGrid) {
+                    if ($this->candidatesOnEachUnknownBoxeOf($testBox->neighbourhood)) {
                        $solutions = $this->solutionsGenerator($randomized);
                        foreach($solutions as $solution) {
                            $stop = (yield $solution);
@ -175,11 +221,20 @@
            }
        }

+        function candidatesOnEachUnknownBoxeOf($area) {
+            foreach($area as $box) {
+                if (($box->value == UNKNOWN) && (count($box->candidates) == 0)) {
+                    return false;
+                }
+            }
+            return true;
+        }
+        
        function toString() {
            $str = "";
            foreach($this->rows as $row) {
                forEach($row as $box) {
-                    $str .= ($box->value? $box->value : UNKNOWN);
+                    $str .= $box->value;
                }
            }
            return $str;
--- a/favicon.php
+++ b/favicon.php
@ -1,61 +0,0 @@
-<?php
-    header ("Content-type: image/png");
-    const UNKNOWN = ".";
-    $gridStr = strip_tags($_GET['grid']);
-    $size = (int) $_GET['size'];
-    $icon = imagecreate($size, $size);
-    $transparent = imagecolorallocate($icon, 1, 1, 1);
-    imagecolortransparent($icon, $transparent);
-    $gridBorder = imagecolorallocate($icon, 0, 0, 0);
-    $known = imagecolorallocate($icon, 102, 102, 255);
-    $unknown = imagecolorallocate($icon, 255, 255, 255);
-    
-    if ($size == 16) {
-        ImageLine($icon,  2,  1, 12,  1, $gridBorder);
-        ImageLine($icon,  2,  5, 12,  5, $gridBorder);
-        ImageLine($icon,  2,  9, 12,  9, $gridBorder);
-        ImageLine($icon,  2, 13, 12, 13, $gridBorder);
-        ImageLine($icon,  1,  2,  1, 12, $gridBorder);
-        ImageLine($icon,  5,  2,  5, 12, $gridBorder);
-        ImageLine($icon,  9,  2,  9, 12, $gridBorder);
-        ImageLine($icon, 13,  2, 13, 12, $gridBorder);
-        $x = 1;
-        $y = 0;
-        foreach(str_split($gridStr) as $i => $value) {
-            $x++;
-            if ($i % 3 == 0) $x++;
-            if ($i % 9 == 0) {
-                $y++;
-                $x = 2;
-            }
-            if ($i % 27 == 0) $y++;
-            if ($value == UNKNOWN) $pixelColor = $unknown;
-            else $pixelColor = $known;
-            ImageSetPixel($icon, $x, $y, $pixelColor);
-        }
-    } else {
-        $boxSize = floor(($size-5) / 9);
-        $start = 1;
-        $end = 9*$boxSize + 2;
-        for ($y=0; $y < $size; $y += 3*$boxSize + 1)
-            ImageLine($icon,  $start,  $y, $end,  $y, $gridBorder);
-        for ($x=0; $x < $size; $x += 3*$boxSize +1)
-            ImageLine($icon,  $x,  $start,  $x, $end, $gridBorder);
-        $x = 0;
-        $y = 0;
-        $boxSizeMinusOne = $boxSize - 1;
-        foreach(str_split($gridStr) as $i => $value) {
-            if ($i % 3 == 0) $x++;
-            if ($i % 27 == 0) $y++;
-            if ($value == UNKNOWN) $color = $unknown;
-            else $color = $known;
-            imagefilledrectangle($icon, $x, $y, $x+$boxSizeMinusOne, $y+$boxSizeMinusOne, $color);
-            $x += $boxSize;
-            if ($i % 9 == 8) {
-                $y += $boxSize;
-                $x = 0;
-            }
-        }
-    }
-    imagepng($icon);
-?>
--- a/favicon.png
+++ b/favicon.png
--- a/game.php
+++ b/game.php
@ -1,129 +0,0 @@
-<?php
-    require("classes.php");
-
-    $gridStr = basename(strip_tags($_SERVER["REQUEST_URI"]));
-    // URL contains grid
-    if (preg_match("#^[1-9.]{81}$#", $gridStr)) {
-?>
-<!DOCTYPE html>
-<html lang='fr'>
-    <head>
-        <meta charset='utf-8' />
-        <meta name='viewport' content='width=device-width' />
-        <title>Sudoku</title>
-        <link rel='stylesheet' type='text/css' href='style.css' />
-        <script src='app.js'></script>
-        <link rel="icon" type="image/png" href="favicon.php?size=16&grid=<?=$gridStr?>" sizes="16x16">
-        <link rel="icon" type="image/png" href="favicon.php?size=32&grid=<?=$gridStr?>" sizes="32x32">
-    </head>
-    <body>
-        <header>
-            <h1>Sudoku</h1>
-        </header>
-        <section>
-            Remplissez la grille de sorte que chaque ligne, colonne et région (carré de 3×3 cases) contienne tous les chiffres de 1 à 9.
-        </section>
-        <form id='sudokuForm'>
-            <div>
-                <table id='grid' class='grid'>
-                    <tbody>
-<?php
-        for ($row = 0; $row < 9; $row++) {
-?>
-                        <tr>
-<?php
-            for ($column = 0; $column < 9; $column++) {
-                $value = $gridStr[9*$row+$column];
-?>
-                            <td>
-<?php
-                if ($value == UNKNOWN) {
-?>
-                                <input type='number' min='1' max='9' step='1' value='' title='Valeurs possibles [Clic-droit]'/>
-<?php
-                } else {
-?>
-                                <input type='number' min='1' max='9' step='1' value='<?=$value?>' disabled/>
-<?php
-                }
-?>
-                            </td>
-<?php
-            }
-?>
-                        </tr>
-<?php
-        }
-?>
-                    </tbody>
-                </table>
-            </div>
-            <div id='buttons' class='highlight-buttons'>
-<?php
-        for($value=1; $value<=9; $value++) {
-            echo "                <button type='button' onclick='highlight(\"$value\")' title='Surligner les $value'  accesskey='$value'>$value</button>\n";
-        }
-?>
-            </div>
-            <div>
-                <button id='inkPenButton' type='button' onclick='useInkPen()' title='Stylo' class='pressed'>
-                    <img src="img/ink-pen.png" alt='Stylo' width=16 height=16/>
-                </button>
-                <button id='pencilButton' type='button' onclick='usePencil()' title='Crayon'>
-                    <img src="img/pencil.png" alt='Crayon' width=16 height=16/>
-                </button>
-                <button type='button' onclick='erasePencil()' title='Effacer le crayon'>
-                    <img src="img/pencil-eraser.png" alt="Gomme blanche" width=16 height=16/>
-                </button>
-                <button class="warning" type='button' onclick='eraseAll()' title='Effacer tout'>
-                    <img src="img/ink-eraser.png" alt="Gomme bleue" width=16 height=16/>
-                </button>
-                <button id='undoButton' type='button' onclick='undo()' disabled title='Annuler' accesskey='z'>
-                    <img src="img/undo.png" alt="Annuler" width=16 height=16/>
-                </button>
-                <!--<input id='colorPicker' type='color' title='Changer de couleur de stylo' value='#00008b'/> -->
-            </div>
-        </form>
-        <ul id="contextMenu" class="context-menu">
-        </ul>
-        <footer>
-            <a href=''>Lien vers cette grille</a><br/>
-            <a href='.'>Nouvelle grille</a>
-        </footer>
-    </body>
-</html>
-<?php
-    } else {
-    	$grid = new Grid();
-    	$grid->generate();
-
-        header("HTTP/1.0 400 Bad Request", true, 400);
-
-    	$urlDir = $_SERVER["REQUEST_SCHEME"] . "://" . $_SERVER["HTTP_HOST"] . dirname($_SERVER["DOCUMENT_URI"]);
-        $urlExample = $urlDir . "/" . $grid->toString();
-?>
-<!DOCTYPE html>
-<html lang='fr'>
-    <head>
-        <meta charset='utf-8' />
-        <meta name='viewport' content='width=device-width' />
-        <title>Grille incorrecte</title>
-        <link rel='stylesheet' type='text/css' href='style.css' />
-        <link rel="icon" type="image/png" href="favicon.png">
-    </head>
-    <body>
-        <header>
-            <h1>Grille incorrecte</h1>
-        </header>
-        L'adresse URL doit être de la forme : <?=$urlDir?>/<em>grille</em>,<br/>
-        <em>grille</em> étant une suite de 81 caractères représentant la grille de gauche à droite puis de haut en bas, soit :
-        <ul>
-            <li>un chiffre entre 1 et 9 pour les cases connues</li>
-            <li>un point pour les case vides</li>
-        </ul>
-        Exemple : <a href='<?=$urlExample?>'><?=$urlExample?></a><br/>
-    </body>
-</html>
-<?php
-    }
-?>
--- a/head.php
+++ b/head.php
@ -0,0 +1,32 @@
+        <meta charset="utf-8" />
+        <title>Sudoku</title><meta property="og:title" content="Sudoku" />
+        <meta property="og:type" content="game" />
+        <meta name="description" property="og:description" content="Remplissez la grille de sorte que chaque ligne, colonne et région (carré de 3×3 cases) contienne tous les chiffres de 1 à 9." />
+        <link rel="canonical" href="<?=$_SERVER["REQUEST_SCHEME"]."://".$_SERVER["HTTP_HOST"].dirname($_SERVER["DOCUMENT_URI"])?>" />
+        <meta property="og:url" content="<?=$_SERVER["REQUEST_SCHEME"]."://".$_SERVER["HTTP_HOST"].$_SERVER["DOCUMENT_URI"]?>" />
+        <meta property="og:image" content="<?=$_SERVER["REQUEST_SCHEME"]."://".$_SERVER["HTTP_HOST"].dirname($_SERVER["DOCUMENT_URI"])?>/thumbnail.php?size=200&grid=<?=$currentGrid?>" />
+        <meta property="og:image:width" content="200" />
+        <meta property="og:image:height" content="200" />
+        <meta name="Language" CONTENT="fr" /><meta property="og:locale" content="fr_FR" />
+        <meta property="og:site_name" content="<?=$_SERVER["HTTP_HOST"]?>" />
+        
+        <meta name="viewport" content="width=device-width, initial-scale=1" />
+
+        <link href="https://cdn.jsdelivr.net/npm/bootstrap-dark-5@1.1.3/dist/css/bootstrap-dark.min.css" rel="stylesheet">
+        <link href="https://cdn.jsdelivr.net/npm/remixicon@3.2.0/fonts/remixicon.css" rel="stylesheet">
+        <link href="style.css" rel="stylesheet" type="text/css" />
+
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=196" sizes="196x196" rel="icon" type="image/png">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=160" sizes="160x160" rel="icon" type="image/png">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=96"  sizes="96x96"   rel="icon" type="image/png">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=16"  sizes="16x16"   rel="icon" type="image/png">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=32"  sizes="32x32"   rel="icon" type="image/png">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=152" sizes="152x152" rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=144" sizes="144x144" rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=120" sizes="120x120" rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=114" sizes="114x114" rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=57"  sizes="57x57"   rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=72"  sizes="72x72"   rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=60"  sizes="60x60"   rel="apple-touch-icon">
+        <link href="thumbnail.php?grid=<?=$currentGrid?>&size=76"  sizes="76x76"   rel="apple-touch-icon">
+        <link href="manifest.php?grid=<?=$currentGrid?>" rel="manifest">
--- a/img/ink-eraser.png
+++ b/img/ink-eraser.png
--- a/img/ink-pen.png
+++ b/img/ink-pen.png
--- a/img/pencil-eraser.png
+++ b/img/pencil-eraser.png
--- a/img/pencil.png
+++ b/img/pencil.png
--- a/img/undo.png
+++ b/img/undo.png
--- a/index.php
+++ b/index.php
@ -1,8 +1,45 @@
 <?php 
    require("classes.php");

-    $grid = new Grid();
-    $grid->generate();
-    header("Location: " . $_SERVER["REQUEST_SCHEME"] . "://" . $_SERVER["HTTP_HOST"] . dirname($_SERVER["DOCUMENT_URI"]) . "/" . $grid->toString());
-    exit();
+    $fullUrl = $_SERVER["REQUEST_SCHEME"]."://".$_SERVER["HTTP_HOST"].$_SERVER["DOCUMENT_URI"];
+    $dirUrl = dirname($fullUrl);
+    $currentGrid = strip_tags($_SERVER['QUERY_STRING']);
+
+    if (preg_match("/^[1-9-]{81}$/", $currentGrid)) {
+        session_id($currentGrid);
+        session_start(["use_cookies" => false]);
+
+        if (!array_key_exists("nbSolutions", $_SESSION)) {
+            $grid = new Grid($currentGrid);
+            $_SESSION["nbSolutions"] = $grid->containsDuplicates() ? -1 : $grid->countSolutions(2);
+        }
+        switch($_SESSION["nbSolutions"]) {
+            case -1:
+                $warning = "Cette grille contient des doublons.";
+                break;
+            case 0:
+                $warning = "Cette grille n'a pas de solution.";
+                break;
+            case 1:
+                break;
+            default:
+                $warning = "Cette grille a plusieurs solutions.";
+        }
+        require("sudoku.php");
+    } else {
+        if ($currentGrid) {
+            require("400.php");
+        } else {
+            $grid = new Grid();
+            $gridAsString = $grid->toString();
+            $newGridUrl = "$dirUrl/?$gridAsString";
+    
+            session_id($gridAsString);
+            session_start(["use_cookies" => false]);
+    
+            $_SESSION["nbSolutions"] = 1;
+
+            header("Location: $newGridUrl");
+        }
+    }
 ?>
--- a/manifest.php
+++ b/manifest.php
@ -0,0 +1,137 @@
+<?php
+    if (isset($_GET["grid"]))
+        $currentGrid = $_GET["grid"];
+    else
+        $currentGrid = ".";
+?>
+{
+    "short_name": "Sudoku",
+    "name": "Sudoku",
+    "description": "Remplissez la grille de sorte que chaque ligne, colonne et région (carré de 3×3 cases) contienne tous les chiffres de 1 à 9.",
+    "icons": [{
+        "src": "thumbnail.php?size=48&grid=<?=$currentGrid?>",
+        "sizes": "48x48",
+        "type": "image/png"
+    }, {
+        "src": "thumbnail.php?size=72&grid=<?=$currentGrid?>",
+        "sizes": "72x72",
+        "type": "image/png"
+    }, {
+        "src": "thumbnail.php?size=96&grid=<?=$currentGrid?>",
+        "sizes": "96x96",
+        "type": "image/png"
+    }, {
+        "src": "thumbnail.php?size=144&grid=<?=$currentGrid?>",
+        "sizes": "144x144",
+        "type": "image/png"
+    }, {
+        "src": "thumbnail.php?size=168&grid=<?=$currentGrid?>",
+        "sizes": "168x168",
+        "type": "image/png"
+    }, {
+        "src": "thumbnail.php?size=192&grid=<?=$currentGrid?>",
+        "sizes": "192x192",
+        "type": "image/png"
+    }],
+    "start_url": ".",
+    "background_color": "#fff",
+    "display": "standalone",
+    "scope": ".",
+    "theme_color": "#fff",
+    "orientation": "portrait-primary",
+    "shortcuts": [
+        {
+            "name": "Sudoku : cette grille",
+            "short_name": "Ce sudoku",
+            "description": "Continuer cette grille de sudoku",
+            "url": "<?=$currentGrid?>",
+            "icons": [{
+                    "src": "thumbnail.php?size=48&grid=<?=$currentGrid?>",
+                    "sizes": "48x48",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=72&grid=<?=$currentGrid?>",
+                    "sizes": "72x72",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=96&grid=<?=$currentGrid?>",
+                    "sizes": "96x96",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=144&grid=<?=$currentGrid?>",
+                    "sizes": "144x144",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=168&grid=<?=$currentGrid?>",
+                    "sizes": "168x168",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=192&grid=<?=$currentGrid?>",
+                    "sizes": "192x192",
+                    "type": "image/png"
+            }]
+        },
+        {
+            "name": "Sudoku : Grille vierge",
+            "short_name": "Sudoku vierge",
+            "description": "Grille de sudoku vierge",
+            "url": ".................................................................................",
+            "icons": [{
+                    "src": "thumbnail.php?size=48&grid=.................................................................................",
+                    "sizes": "48x48",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=72&grid=.................................................................................",
+                    "sizes": "72x72",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=96&grid=.................................................................................",
+                    "sizes": "96x96",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=144&grid=.................................................................................",
+                    "sizes": "144x144",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=168&grid=.................................................................................",
+                    "sizes": "168x168",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=192&grid=.................................................................................",
+                    "sizes": "192x192",
+                    "type": "image/png"
+            }]
+        },
+        {
+            "name": "Sudoku : Nouvelle grille",
+            "short_name": "Nouveau sudoku",
+            "description": "Nouvelle grille de sudoku",
+            "url": ".",
+            "icons": [{
+                    "src": "thumbnail.php?size=48&grid=.528.3....4.9.1...39.562......73.129...1.64.7...42.3656.13.5...28.6.4...4.5287...",
+                    "sizes": "48x48",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=72&grid=.528.3....4.9.1...39.562......73.129...1.64.7...42.3656.13.5...28.6.4...4.5287...",
+                    "sizes": "72x72",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=96&grid=.528.3....4.9.1...39.562......73.129...1.64.7...42.3656.13.5...28.6.4...4.5287...",
+                    "sizes": "96x96",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=144&grid=.528.3....4.9.1...39.562......73.129...1.64.7...42.3656.13.5...28.6.4...4.5287...",
+                    "sizes": "144x144",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=168&grid=.528.3....4.9.1...39.562......73.129...1.64.7...42.3656.13.5...28.6.4...4.5287...",
+                    "sizes": "168x168",
+                    "type": "image/png"
+                }, {
+                    "src": "thumbnail.php?size=192&grid=.528.3....4.9.1...39.562......73.129...1.64.7...42.3656.13.5...28.6.4...4.5287...",
+                    "sizes": "192x192",
+                    "type": "image/png"
+            }]
+        }
+    ]
+}
--- a/nginx-example.conf
+++ b/nginx-example.conf
@ -1,23 +0,0 @@
-location /sudoku/ {
-	alias /var/www/sudoku/;
-	index index.php;
-	try_files $uri $uri/ @sudoku;
-
-	location ~ [^/]\.php(/|$) {
-		fastcgi_split_path_info ^(.+?\.php)(/.*)$;
-		fastcgi_pass unix:/var/run/php/php7.3-fpm-sudoku.sock;
-		fastcgi_index index.php;
-		include fastcgi_params;
-		fastcgi_param REMOTE_USER $remote_user;
-		fastcgi_param PATH_INFO $fastcgi_path_info;
-		fastcgi_param SCRIPT_FILENAME $request_filename;
-	}
-}
-
-location @sudoku {
-    fastcgi_pass unix:/var/run/php/php7.3-fpm-sudoku.sock;
-    include fastcgi_params;
-    fastcgi_param REMOTE_USER $remote_user;
-    fastcgi_param PATH_INFO $fastcgi_path_info;
-    fastcgi_param SCRIPT_FILENAME sudoku/game.php;
-}
--- a/service-worker.js
+++ b/service-worker.js
@ -0,0 +1,86 @@
+/*
+Copyright 2015, 2019, 2020 Google LLC. All Rights Reserved.
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+ http://www.apache.org/licenses/LICENSE-2.0
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+// Incrementing OFFLINE_VERSION will kick off the install event and force
+// previously cached resources to be updated from the network.
+const OFFLINE_VERSION = 1;
+const CACHE_NAME = "offline";
+// Customize this with a different URL if needed.
+const OFFLINE_URL = ".";
+
+self.addEventListener("install", (event) => {
+  event.waitUntil(
+    (async () => {
+      const cache = await caches.open(CACHE_NAME);
+      // Setting {cache: 'reload'} in the new request will ensure that the
+      // response isn't fulfilled from the HTTP cache; i.e., it will be from
+      // the network.
+      await cache.add(new Request(OFFLINE_URL, { cache: "reload" }));
+    })()
+  );
+  // Force the waiting service worker to become the active service worker.
+  self.skipWaiting();
+});
+
+self.addEventListener("activate", (event) => {
+  event.waitUntil(
+    (async () => {
+      // Enable navigation preload if it's supported.
+      // See https://developers.google.com/web/updates/2017/02/navigation-preload
+      if ("navigationPreload" in self.registration) {
+        await self.registration.navigationPreload.enable();
+      }
+    })()
+  );
+
+  // Tell the active service worker to take control of the page immediately.
+  self.clients.claim();
+});
+
+self.addEventListener("fetch", (event) => {
+  // We only want to call event.respondWith() if this is a navigation request
+  // for an HTML page.
+  if (event.request.mode === "navigate") {
+    event.respondWith(
+      (async () => {
+        try {
+          // First, try to use the navigation preload response if it's supported.
+          const preloadResponse = await event.preloadResponse;
+          if (preloadResponse) {
+            return preloadResponse;
+          }
+
+          // Always try the network first.
+          const networkResponse = await fetch(event.request);
+          return networkResponse;
+        } catch (error) {
+          // catch is only triggered if an exception is thrown, which is likely
+          // due to a network error.
+          // If fetch() returns a valid HTTP response with a response code in
+          // the 4xx or 5xx range, the catch() will NOT be called.
+          console.log("Fetch failed; returning offline page instead.", error);
+
+          const cache = await caches.open(CACHE_NAME);
+          const cachedResponse = await cache.match(OFFLINE_URL);
+          return cachedResponse;
+        }
+      })()
+    );
+  }
+
+  // If our if() condition is false, then this fetch handler won't intercept the
+  // request. If there are any other fetch handlers registered, they will get a
+  // chance to call event.respondWith(). If no fetch handlers call
+  // event.respondWith(), the request will be handled by the browser as if there
+  // were no service worker involvement.
+});
--- a/style.css
+++ b/style.css
@ -1,212 +1,161 @@
-body {
-    font-family: sans-serif;
-    width: min-content;
-    margin: auto;
-}
-
-h1 {
-    text-align: center;
-    margin: 1rem;
-}
-
-section, div, footer {
-    display: flex;
-    flex-wrap: wrap;
-    align-items: center;
-    row-gap: 0.5rem;
-    column-gap: 0.5rem;
-    margin: 0.8rem auto;
-    justify-content: center;
-    text-align: center;
-}
-
-.grid {
-    border-spacing: 0;
-    border: 1px solid black;
-    border-radius: 6px;
-}
-.grid td, tr {
-    padding: 0;
-}
-.grid tr:first-child td:first-child {
-    border-top-left-radius: 5px;
-}
-.grid tr:first-child td:first-child input {
-    border-top-left-radius: 4px;
-}
-.grid tr:first-child td:last-child {
-    border-top-right-radius: 5px;
-}
-.grid tr:first-child td:last-child input {
-    border-top-right-radius: 4px;
-}
-.grid tr:last-child td:first-child {
-    border-bottom-left-radius: 5px;
-}
-.grid tr:last-child td:first-child > input {
-    border-bottom-left-radius: 4px;
-}
-.grid tr:last-child td:last-child {
-    border-bottom-right-radius: 5px;
-}
-.grid tr:last-child td:last-child input {
-    border-bottom-right-radius: 4px;
-}
-.grid tr:nth-child(3n+1) td {
-    border-top: 1px solid black;
-}
-.grid tr:nth-child(3n+2) td {
-    border-top: 1px solid grey;
-    border-bottom: 1px solid grey;
-}
-.grid tr:nth-child(3n) td {
-    border-bottom: 1px solid black;
-}
-.grid td:nth-child(3n+1) {
-    border-left: 1px solid black;
-}
-.grid td:nth-child(3n+2) {
-    border-left: 1px solid grey;
-    border-right: 1px solid grey;
-}
-.grid td:nth-child(3n+3) {
-    border-right: 1px solid black;
-}
-
-.grid input {
-    width: 2.5rem;
-    height: 2.5rem;
-    font-size: 1.5rem;
-    border: 0;
-    padding: 0;
-    text-align: center;
-    transition: background 0.5s;
-    -moz-appearance: textfield;
-}
-input::-webkit-outer-spin-button,
+input[type="number"]::-webkit-outer-spin-button,
 input::-webkit-inner-spin-button {
-    -webkit-appearance: none;
-    margin: 0;
+    -webkit-appearance: none !important;
+    margin: 0 !important;
 }
-input::-webkit-calendar-picker-indicator {
-    display: none;
+
+input[type="number"]::-webkit-calendar-picker-indicator {
+    display: none !important;
 }
-.grid input:enabled {
-    background: white;
-    color: darkblue;
+
+table {
+    border-collapse: separate;
+    border-spacing: 0;
 }
-.grid input:disabled, button:enabled {
-    color: white;
-    background: #6666ff;
-}
-.grid input.forbidden-value:enabled {
-    background: #ffff77;
-}
-.grid input.same-value:enabled {
-    background: #ffff33;
-}
-.grid input.forbidden-value:disabled {
-    color: #ffff99;
-    background: #6666ff;
-}
-.grid input.same-value:disabled, button.same-value:enabled {
-    color: #ffff99 !important;
-    background: #00cc66 !important;
-}
-.grid input.pencil, input::placeholder {
-    color: #888 !important;
-    font-size: 1rem !important;
+
+table input {
    width: 2.5rem !important;
    height: 2.5rem !important;
+    font-size: 1.3rem !important;
+    padding: 0 !important;
+    margin: 0 !important;
+    text-align: center;
+    appearance: textfield !important;
+    border-radius: 0 !important;
 }

-.highlight-buttons {
-    column-gap: 2px;
-}
-button, input[type="color"] {
-    border: 2px outset #6666ff;
-    border-radius: 4px;
-    font-size: 1.3rem;
-    padding: 4px 9px 5px 9px;
-    margin:  0px 1px 1px 1px;
-}
-button:enabled:hover {
-    border-width: 1px;
-    border-style: outset;
-    padding: 5px 9px 5px 10px;
-    margin:  1px 1px 1px 2px;
-}
-button.pressed:enabled:hover {
-    border-width: 3px;
-    border-style: inset;
-    padding: 4px 6px 2px 9px;
-    margin:  1px 1px 1px 2px;
-}
-button.pressed {
-    border: 2px inset #00cc66;
-    background: #00cc66;
-    padding: 4px 8px 4px 9px;
-    margin:  1px 1px 0px 2px;
-}
-button:enabled:active {
-    border-width: 4px !important;
-    border-style: inset !important;
-    padding: 4px 4px 0px 9px !important;
-    margin:  0px 1px 0px 2px !important;
-}
-button:disabled {
-    color: #666;
-    background: darkgrey;
-    border: 1px outset darkgrey;
-    padding: 5px 10px 6px 10px;
-    margin:  0px 1px 1px 1px;
-}
-button.warning {
-    background: #ff5050;
-    border-color: #ff5050;
-}
-input[type="color"] {
-    padding: 0;
+table td.table-primary input,
+table td.table-active input,
+table.table-success input,
+td.table-danger input:disabled,
+table input:not([disabled]) {
+    background: transparent !important;
+    color: inherit !important;
 }

-a {
-    text-decoration: none;
+table input:not([disabled]):hover {
+    background: #9fb9b945 !important;
 }

-.context-menu {
-    display: none;
-    z-index: 1000;
-    position: absolute;
-    overflow: hidden;
-    border: 1px solid #CCC;
-    white-space: nowrap;
-    font-family: sans-serif;
-    background: #EEE;
-    color: #333;
-    border-top-right-radius: 3px;
-    border-bottom-left-radius: 3px;
-    border-bottom-right-radius: 3px;
-    padding: 0;
-    margin: 0;
+table input:disabled {
+    background-position: center !important;
+}
+
+tr:nth-child(3n+1) td input {
+    border-top-width: 3px !important;
+}
+
+tr:last-child td input {
+    border-bottom-width: 3px !important;
+}
+
+td:nth-child(3n+1) input {
+    border-left-width: 3px !important;
+}
+
+td:last-child input {
+    border-right-width: 3px !important;
+}
+
+tr:first-child td:first-child {
+    border-top-left-radius: .7rem !important;
+}
+
+tr:first-child td:first-child input {
+    border-top-left-radius: .5rem !important;
+}
+
+tr:first-child td:last-child {
+    border-top-right-radius: .7rem !important;
+}
+
+tr:first-child td:last-child input {
+    border-top-right-radius: .5rem !important;
+}
+
+tr:last-child td:first-child {
+    border-bottom-left-radius: .7rem !important;
+}
+
+tr:last-child td:first-child input {
+    border-bottom-left-radius: .5rem !important;
+}
+
+tr:last-child td:last-child {
+    border-bottom-right-radius: .7rem !important;
+}
+
+tr:last-child td:last-child input {
+    border-bottom-right-radius: .5rem !important;
+}
+
+td {
+    padding: 0 !important;
+    margin: 0 !important;
+    border: 0 !important;
+}
+
+td,
+table input {
+    transition: background-color .4s, box-shadow .4s !important;
 }

 .context-menu li {
-    padding: 6px 10px;
    cursor: default;
-    list-style-type: none;
-    transition: all .3s ease;
-    user-select: none;
-    font-size: 1rem;
 }

-.context-menu li:hover {
-    background-color: #DEF;
+.table-active {
+    cursor: inherit !important;
 }

-.context-menu li.error {
-    color: #888
+.not-allowed {
+    cursor: not-allowed !important;
 }

-.context-menu li.error:hover {
-    background-color: #EEE;
+table {
+    cursor: text;
+}
+
+button,
+label {
+    /*! padding: .375rem .65rem !important; */
+    cursor: pointer;
+}
+
+button i,
+label i {
+   margin: 0 -.125rem;
+}
+
+button:disabled,
+:disabled+label {
+    cursor: not-allowed !important;
+}
+
+table input:enabled {
+    cursor: inherit;
+}
+
+.pencil {
+    color: var(--bs-secondary-color) !important;
+}
+
+#colorPickerInput{
+    width: 2.3rem;
+    height: auto;
+    padding: .375rem;
+}
+
+#colorPickerLabel {
+    color: var(--bs-body-color);
+}
+
+@media (prefers-color-scheme:dark) {
+    .pencil {
+        color: #5a5a5a !important;
+    }
+}
+
+.context-menu {
+    z-index: 100;
 }
--- a/sudoku.js
+++ b/sudoku.js
@ -0,0 +1,394 @@
+const VALUES  = "123456789"
+const UNKNOWN = '.'
+
+let boxes         = []
+let rows          = Array.from(Array(9), x => [])
+let columns       = Array.from(Array(9), x => [])
+let regions       = Array.from(Array(9), x => [])
+let areaNames     = {
+    ligne:   rows,
+    colonne: columns,
+    région:  regions,
+}
+let valueToInsert = ""
+let easyBoxes     = []
+let insertRadios  = []
+
+function shuffle(iterable) {
+    array = Array.from(iterable)
+    if (array.length > 1) {
+        let i, j, tmp
+        for (i = array.length - 1; i > 0; i--) {
+            j = Math.floor(Math.random() * (i + 1))
+            tmp = array[i]
+            array[i] = array[j]
+            array[j] = tmp
+        }
+    }
+    return array
+}
+
+window.onload = function() {
+    let rowId = 0
+    for (let row of grid.getElementsByTagName('tr')) {
+        let columnId = 0
+        for (let box of row.getElementsByTagName('input')) {
+            let regionId = rowId - rowId % 3 + Math.floor(columnId / 3)
+            if (!box.disabled) {
+                box.onfocus      = onfocus
+                box.oninput      = oninput
+                box.onblur       = onblur
+                box.onclick      = onclick
+                box.onmouseenter = onmouseenter
+                box.onmouseleave = onmouseleave
+            }
+            box.oncontextmenu = oncontextmenu
+            box.rowId         = rowId
+            box.columnId      = columnId
+            box.regionId      = regionId
+            boxes.push(box)
+            rows[rowId].push(box)
+            columns[columnId].push(box)
+            regions[regionId].push(box)
+            columnId++
+        }
+        rowId++
+    }
+
+    if (localStorage["tool"] == "sight") sightCheckbox.checked = true
+    else if (localStorage["tool"] == "highlighter") highlighterCheckbox.checked = true
+
+    colorPickerInput.value = window.getComputedStyle(grid).getPropertyValue("--bs-body-color")
+
+    boxes.forEach(box => {
+        box.neighbourhood = new Set(rows[box.rowId].concat(columns[box.columnId]).concat(regions[box.regionId]))
+        box.andNeighbourhood = Array.from(box.neighbourhood)
+        box.neighbourhood.delete(box)
+        box.neighbourhood = Array.from(box.neighbourhood)
+    })
+
+    insertRadios = Array.from(insertRadioGroup.getElementsByTagName("input")).slice(1)
+
+    for (label of document.getElementsByTagName("label")) {
+        label.control.label = label
+    }
+    let accessKeyModifiers = (/Win/.test(navigator.userAgent) || /Linux/.test(navigator.userAgent)) ? "Alt+Maj+"
+                           : (/Mac/.test(navigator.userAgent)) ? "⌃⌥"
+                           : "AccessKey+"
+    for (node of document.querySelectorAll("*[accesskey]")) {
+        shortcut = ` [${node.accessKeyLabel||(accessKeyModifiers+node.accessKey)}]`
+        if (node.title) node.title += shortcut
+        else if (node.label) node.label.title += shortcut
+    }
+
+    loadGame(history.state)
+}
+
+window.onpopstate = (event) => loadGame(event.state)
+
+function loadGame(state) {
+    if (state) {
+        boxes.forEach((box, i) => {
+            if (!box.disabled) {
+                box.value = state.boxesValues[i]
+                box.placeholder = state.boxesPlaceholders[i]
+            }
+        })
+        restartLink.classList.remove("disabled")
+        undoButton.disabled = false
+        fixGridLink.href = "?" + state.boxesValues.map(value => value || UNKNOWN).join("")
+    } else {
+        boxes.filter(box => !box.disabled).forEach(box => {
+            box.value = ""
+            box.placeholder = ""
+        })
+        restartLink.classList.add("disabled")
+        undoButton.disabled = true
+        fixGridLink.href = ""
+    }
+
+    checkBoxes()
+    enableRadio()
+    highlight()
+}
+
+function searchCandidatesOf(box) {
+    box.candidates = new Set(VALUES)
+    box.neighbourhood.forEach(neighbour => box.candidates.delete(neighbour.value))
+    if (!box.disabled) {
+        switch (box.candidates.size) {
+            case 0:
+                box.title = "Aucune possibilité !"
+            break
+            case 1:
+                box.title = "Une seule possibilité [Clic-droit]"
+            break
+            default:
+                box.title = box.candidates.size + " possibilités [Clic-droit]"
+        }
+    }
+}
+
+function onfocus() {
+    if (pencilRadio.checked) {
+        this.type        = "text"
+        this.value       = this.placeholder
+        this.placeholder = ""
+        this.classList.add("pencil")
+    } else {
+        this.select()
+    }
+    if (penColor && inkPenRadio.checked) {
+        this.style.setProperty("color", penColor)
+    }
+    this.style.caretColor = valueToInsert ? "transparent" : "auto"
+}
+
+function onclick() {
+    if (inkPenRadio.checked) {
+        if (valueToInsert) {
+            this.value = valueToInsert
+            this.oninput()
+        } else {
+            this.select()
+        }
+    } else if (pencilRadio.checked) {
+        if (valueToInsert) {
+            this.value = Array.from(new Set(this.value + valueToInsert)).join("")
+            this.oninput()
+        }
+    } else if (eraserRadio.checked) {
+        this.value = ""
+        this.placeholder = ""
+        this.oninput()
+    }
+}
+
+function oninput() {
+    if (inkPenRadio.checked) {
+        checkBoxes()
+        enableRadio()
+        highlight()
+        fixGridLink.href = "?" + boxes.map(box => box.value || UNKNOWN).join("")
+    }
+    saveGame()
+}
+
+function checkBoxes() {
+    boxes.forEach(box => {
+        box.setCustomValidity("")
+        box.classList.remove("is-invalid")
+        box.parentElement.classList.remove("table-danger")
+        searchCandidatesOf(box)
+        if (box.candidates.size == 0) {
+            box.setCustomValidity("Aucun chiffre possible !")
+            box.classList.add("is-invalid")
+        }
+    })
+
+    for (let [areaName, areas] of Object.entries(areaNames))
+        for (area of areas)
+            area.filter(box => box.value).sort((box, neighbour) => {
+                if(box.value == neighbour.value) {
+                    area.forEach(neighbour => neighbour.parentElement.classList.add("table-danger"))
+                    for (neighbour of [box, neighbour]) {
+                        neighbour.setCustomValidity(`Il y a un autre ${box.value} dans cette ${areaName}.`)
+                        neighbour.classList.add("is-invalid")
+                    }
+                }
+                return box.value - neighbour.value
+            })
+
+    if (sudokuForm.checkValidity()) { // Correct grid
+        if (boxes.filter(box => box.value == "").length == 0) {
+            grid.classList.add("table-success")
+            setTimeout(() => {
+                if (confirm(`Bravo ! Vous avez résolu la grille. En voulez-vous une autre ?`))
+                    location = "."
+            }, 400)
+        } else {
+            grid.classList.remove("table-success")
+        }
+    } else { // Errors on grid
+        grid.classList.remove("table-success")
+        sudokuForm.reportValidity()
+    }
+}
+
+function enableRadio() {
+    for (radio of insertRadios) {
+        if (boxes.filter(box => box.value == "").some(box => box.candidates.has(radio.value))) {
+            radio.disabled = false
+            radio.label.title = `Insérer un ${radio.value} [${radio.accessKeyLabel||(accessKeyModifiers+radio.accessKey)}]`
+        } else {
+            radio.disabled = true
+            radio.label.title = `Tous les ${radio.value} sont posés.`
+            if (valueToInsert == radio.value) {
+                insertRadio0.checked = true
+                valueToInsert = ""
+                grid.style.cursor = "text"
+            }
+        }
+    }
+}
+
+function highlight() {
+    hintButton.disabled = true
+    easyBoxes = []
+    boxes.forEach(box => {
+        if (valueToInsert && box.value == valueToInsert) {
+            box.parentElement.classList.add("table-primary")
+            box.tabIndex = -1
+        } else {
+            box.parentElement.classList.remove("table-primary")
+            box.tabIndex = 0
+        }
+        
+        if (valueToInsert && highlighterCheckbox.checked && !box.candidates.has(valueToInsert)) {
+            box.parentElement.classList.add("table-active")
+            box.tabIndex = -1
+        } else {
+            box.parentElement.classList.remove("table-active")
+            box.tabIndex = 0
+        }
+        
+        if (!box.value && box.candidates.size == 1) {
+            hintButton.disabled = false
+            easyBoxes.push(box)
+        }
+    })
+    highlighterCheckbox.label.title = "Surligner les lignes, colonnes et régions contenant déjà " + (valueToInsert ? "un " + valueToInsert : "le chiffre sélectionné")
+}
+
+function onblur() {
+    if (this.classList.contains("pencil")) {
+        this.placeholder = this.value
+        this.value = ""
+        this.type = "number"
+        this.classList.remove("pencil")
+    }
+}
+
+function saveGame() {
+    history.pushState({
+        boxesValues: boxes.map(box => box.value),
+        boxesPlaceholders: boxes.map(box => box.placeholder)
+    }, "")
+    restartLink.classList.remove("disabled")
+    undoButton.disabled = false
+}
+
+function onmouseenter(event) {
+    if (sightCheckbox.checked){
+        box = event.target
+        box.andNeighbourhood.forEach(neighbour => {
+            neighbour.parentElement.classList.add("table-active")
+        })
+
+        box.neighbourhood.forEach(neighbour => {
+            if (valueToInsert && neighbour.value == valueToInsert) {
+                for (neighbour of [box, neighbour]) {
+                    neighbour.parentElement.classList.add("table-danger", "not-allowed")
+                }
+            }
+        })
+    }
+}
+
+function onmouseleave(event) {
+    if (sightCheckbox.checked){
+        box = event.target
+        box.andNeighbourhood.forEach(neighbour => {
+            neighbour.parentElement.classList.remove("table-active", "table-danger", "not-allowed")
+        })
+    }
+}
+
+function insert(radio) {
+    if (radio.value && valueToInsert == radio.value) {
+        radio.blur()
+        insertRadio0.checked = true
+        insert(0)
+    } else {
+        valueToInsert = radio.value
+        grid.style.cursor = valueToInsert ? "pointer" : "text"
+        highlight()
+    }
+}
+
+let penColor
+
+function changeColor() {
+    penColor = colorPickerInput.value
+    colorPickerLabel.style.color = colorPickerInput.value
+}
+
+function restart() {
+    if (confirm("Effacer toutes les cases ?")) {
+        restartButton.disabled = true
+        location.hash = ""
+    }
+}
+
+function showHint() {
+    if (easyBoxes.length) {
+        shuffle(easyBoxes)
+        let box = easyBoxes.pop()
+        box.placeholder = "💡"
+        box.focus()
+        return box
+    }
+    hintButton.disabled = true
+}
+
+function oncontextmenu(event) {
+    event.preventDefault()
+    while (contextMenu.firstChild) contextMenu.firstChild.remove()
+    const box = event.target
+    if (box.candidates.size) {
+        Array.from(box.candidates).sort().forEach(candidate => {
+            li = document.createElement("li")
+            li.innerText = candidate
+            li.classList = "list-group-item list-group-item-action"
+            li.onclick = function(e) {
+                contextMenu.style.display = "none"
+                valueToInsert = e.target.innerText
+                grid.style.cursor = "pointer"
+                document.getElementById("insertRadio" + valueToInsert).checked = true
+                box.onclick()
+            }
+            li.oncontextmenu = function(e) {
+				e.preventDefault()
+				li.onclick(e)
+            }
+            contextMenu.appendChild(li)
+        })
+    } else {
+        li = document.createElement("li")
+        li.innerText = "Aucune possibilité !"
+        li.classList = "list-group-item list-group-item-action disabled"
+        contextMenu.appendChild(li)
+    }
+    contextMenu.style.left = `${event.pageX}px`
+    contextMenu.style.top = `${event.pageY}px`
+    contextMenu.style.display = "block"
+
+    document.onclick = function(event) {
+        contextMenu.style.display = "none"
+        document.onclick = null
+    }
+    return false
+}
+
+document.onkeydown = function(event) {
+    if (event.key == "Escape" && contextMenu.style.display == "block") {
+        event.preventDefault()
+        contextMenu.style.display = "none"
+    }
+}
+
+window.onbeforeunload = function(event) {
+    saveGame()
+    if (sightCheckbox.checked) localStorage["tool"] = "sight"
+    else if (highlighterCheckbox.checked) localStorage["tool"] = "highlighter"
+}
--- a/sudoku.php
+++ b/sudoku.php
@ -0,0 +1,90 @@
+<!DOCTYPE html>
+<html lang='fr' prefix="og: https://ogp.me/ns#">
+
+    <head>
+<?php require_once("head.php") ?>
+    </head>
+
+    <body>
+        <nav class="navbar mb-4">
+            <h1 class="display-4 text-center m-auto">Sudoku</h1>
+        </nav>
+        <div class="row g-0">
+            <main class="col-md-6 order-md-1">
+                <div class="text-center m-auto" style="width: min-content;">
+                    <div class='d-flex justify-content-between mb-2'>
+                        <div class='btn-group'>
+                            <input type='radio' id='inkPenRadio' class='btn-check' name='penRadioGroup' checked />
+                            <label for='inkPenRadio' class='btn btn-primary' title='Écrire un chiffre'><i class="ri-ball-pen-fill"></i></label>
+                            <input type='radio' id='pencilRadio' class='btn-check' name='penRadioGroup' />
+                            <label for='pencilRadio' class='btn btn-primary' title='Prendre des notes'><i class="ri-pencil-fill"></i></label>
+                            <input type='radio' id='eraserRadio' class='btn-check' name='penRadioGroup' />
+                            <label for='eraserRadio' class='btn btn-primary' title='Effacer une case'><i class="ri-eraser-fill"></i></label>
+                        </div>
+                        <input type="color" class="btn-check" id="colorPickerInput" title="Changer la couleur" oninput="changeColor()"/>
+                        <label id="colorPickerLabel" for="colorPickerInput" class="btn btn-primary" title="Changer de couleur"><i class="ri-palette-fill"></i></label>
+                        <div class='btn-group'>
+                            <input type='checkbox' id='sightCheckbox' class='btn-check' onclick='highlighterCheckbox.checked = false; highlight()' />
+                            <label for='sightCheckbox' class='btn btn-info' title='Surligner la ligne, la colonne et la région de la case survolée'><i class="ri-focus-3-line"></i></label>
+                            <input type='checkbox' id='highlighterCheckbox' class='btn-check' onclick='sightCheckbox.checked = false; highlight()' />
+                            <label for='highlighterCheckbox' class='btn btn-info' title='Surligner les lignes, colonnes et régions contenant déjà le chiffre sélectionné'><i class="ri-mark-pen-fill"></i></label>
+                        </div>
+                        <button id="hintButton" type="button" class='btn btn-info' onclick="showHint()" title="Montrer une case avec une seule possibilité" accesskey="H" disabled=""><i class="ri-lightbulb-line"></i></button>
+                        <a id='restartLink' class='btn btn-primary disabled' href="" title='Recommencer'><i class="ri-restart-line"></i></a>
+                        <button id='undoButton' type='button' class='btn btn-primary' onclick='window.history.back()' disabled title='Annuler' accesskey='Z'><i class="ri-arrow-go-back-fill"></i></button>
+                    </div>
+                    <form id='sudokuForm' class='needs-validation' novalidate>
+                        <table id='grid' class='table mb-2'>
+                            <tbody>
+<?php for ($row = 0; $row < 81; $row += 9): ?>
+                                <tr class="input-group d-inline-block w-auto">
+    <?php for ($column = 0; $column < 9; $column++): $value = $currentGrid[$row+$column]; ?>
+        <?php if ($value == UNKNOWN): ?>
+                                    <td><input type='number' min='1' max='9' step='1' value=''  class='form-control' /></td>
+        <?php else: ?>
+                                    <td><input type='number' min='1' max='9' step='1' value='<?=$value?>' class='form-control' disabled /></td>
+        <?php endif ?>
+    <?php endfor?>
+                                </tr>
+<?php endfor?>
+                            </tbody>
+                        </table>
+                    </form>
+                    <div class='d-flex mb-4'>
+                        <div id='insertRadioGroup' class='radioGroup btn-group flex-fill'>
+                            <input type='radio' class='btn-check' id='insertRadio0' value=''  name='insertRadioGroup' onclick='insert(this)' accesskey='0' checked  /><label for='insertRadio0' class='btn btn-primary' title='Clavier'><i class="ri-input-cursor-move"></i></label>
+<?php for($value=1; $value<=9; $value++): ?>
+                            <input type='radio' class='btn-check' id='insertRadio<?=$value?>' value='<?=$value?>' name='insertRadioGroup' onclick='insert(this)' accesskey='<?=$value?>' disabled />
+                            <label for='insertRadio<?=$value?>' class='btn btn-primary' title='Insérer un <?=$value?>'><?=$value?></label>
+<?php endfor ?>
+                        </div>
+                    </div>
+                    <div class='mb-3'>
+<?php if (isset($warning)): ?>
+                        <strong>⚠️ <?=$warning?> ⚠️</strong><br/>
+<?php else: ?>
+                    Remplissez la grille de sorte que chaque ligne, colonne et région (carré de 3×3 cases) contienne tous les chiffres de 1 à 9.
+<?php endif?>
+                    </div>
+                </div>
+            </main>
+            <aside class="col-md-3 text-center text-md-start">
+                <div class="d-flex flex-column flex-shrink-0 p-3">
+                    <ul class="nav nav-pills flex-column">
+                        <li><a href="." class="nav-link link-body-emphasis">Nouvelle grille</a></li>
+                        <li><a href="" class="nav-link link-body-emphasis">Lien vers cette grille</a></li>
+                        <li><a href="?---------------------------------------------------------------------------------" class="nav-link link-body-emphasis">Grille vierge</a></li>
+                        <li><a id="fixGridLink" href="" class="nav-link link-body-emphasis">Figer la grille</a></li>
+                        <li><a href="https://git.malingrey.fr/adrien/Sudoku" class="nav-link link-body-emphasis">Code source</a></li>
+                        <li><a href=".." class="nav-link link-body-emphasis">Autres jeux</a></li>
+                    </ul>
+                </div>
+            </aside>
+        </div>
+        <ul id='contextMenu' class='context-menu modal-content shadow list-group w-auto position-absolute'></ul>
+        <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0-alpha3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ENjdO4Dr2bkBIFxQpeoTz1HIcje39Wm4jDKdf19U8gI4ddQ3GYNS7NTKfAdVQSZe" crossorigin="anonymous"></script>
+        <script src='sudoku.js' defer></script>
+        <script>navigator?.serviceWorker.register('service-worker.js')</script>
+    </body>
+
+</html>
--- a/thumbnail.php
+++ b/thumbnail.php
@ -0,0 +1,120 @@
+<?php
+    require("classes.php");
+    if (isset($_GET["grid"]) && preg_match("/^[1-9-]{81}$/", $_GET["grid"]))
+        $currentGrid = $_GET["grid"];
+    else
+        $currentGrid = "-528-3----4-9-1---39-562------73-129---1-64-7---42-3656-13-5---28-6-4---4-5287---";
+    header ("Content-type: image/png");
+    if (isset($_GET['size']))
+        $size = (int) $_GET['size'];
+    else
+        $size = 196;
+
+    $thumbnail = imagecreate($size, $size);
+    $transparent = imagecolorallocate($thumbnail, 1, 1, 1);
+    imagecolortransparent($thumbnail, $transparent);
+    $darkerBorder = imagecolorallocate($thumbnail, 150, 155, 160);
+    $lighterBorder = imagecolorallocate($thumbnail, 210, 225, 230);
+    $emptyBoxBC = imagecolorallocate($thumbnail, 255, 255, 255);
+    $clueBC = imagecolorallocate($thumbnail, 255, 255, 255);
+    $clueFC = imagecolorallocate($thumbnail, 150, 155, 160);
+    
+    if ($size <= 36) {
+        $boxSize = floor(($size-4) / 9);
+        $gridSize = 9*$boxSize + 4;
+        $start = floor(($size-$gridSize) / 2);
+        $end = $start + $gridSize;
+        $lineStart = $start + 1;
+        $lineEnd = $end - 2;
+        for ($i = $start; $i < $end; $i += 3*$boxSize + 1) {
+            ImageLine($thumbnail,  $lineStart,  $i, $lineEnd,  $i, $darkerBorder);
+            ImageLine($thumbnail,  $i,  $lineStart,  $i, $lineEnd, $darkerBorder);
+        }
+        $x = $start;
+        $y = $start;
+        $boxSizeMinusOne = $boxSize - 1;
+        foreach(str_split($currentGrid) as $i => $value) {
+            if ($i % 3 == 0) $x++;
+            if ($i % 27 == 0) $y++;
+            if ($value == UNKNOWN) {
+                $bgColor = $emptyBoxBC;
+            } else {
+                $bgColor = $clueFC;
+            }
+            imagefilledrectangle($thumbnail, $x, $y, $x+$boxSizeMinusOne, $y+$boxSizeMinusOne, $bgColor);
+            $x += $boxSize;
+            if ($i % 9 == 8) {
+                $y += $boxSize;
+                $x = $start;
+            }
+        }
+    } else if ($size < 82) {
+        $boxSize = floor(($size-1) / 9);
+        $gridSize = 9*$boxSize + 1;
+        $start = floor(($size-$gridSize) / 2);
+        $end = $start + $gridSize;
+        $lineStart = $start + 1;
+        $lineEnd = $end - 2;
+        for ($i = $start + $boxSize; $i < $end - $boxSize; $i += $boxSize) {
+            ImageLine($thumbnail,  $lineStart,  $i, $lineEnd,  $i, $lighterBorder);
+            ImageLine($thumbnail,  $i,  $lineStart,  $i, $lineEnd, $lighterBorder);
+        }
+        for ($i = $start; $i < $end; $i += 3*$boxSize) {
+            ImageLine($thumbnail,  $lineStart,  $i, $lineEnd,  $i, $darkerBorder);
+            ImageLine($thumbnail,  $i,  $lineStart,  $i, $lineEnd, $darkerBorder);
+        }
+        $x = $start + 1;
+        $y = $start + 1;
+        $boxSizeMinusTwo = $boxSize - 2;
+        foreach(str_split($currentGrid) as $i => $value) {
+            if ($value == UNKNOWN) {
+                $bgColor = $emptyBoxBC;
+            } else {
+                $bgColor = $clueFC;
+            }
+            imagefilledrectangle($thumbnail, $x, $y, $x+$boxSizeMinusTwo, $y+$boxSizeMinusTwo, $bgColor);
+            $x += $boxSize;
+            if ($i % 9 == 8) {
+                $y += $boxSize;
+                $x = $start + 1;
+            }
+        }
+    } else {
+        $boxSize = floor(($size-1) / 9);
+        $gridSize = 9*$boxSize + 1;
+        $start = floor(($size-$gridSize) / 2);
+        $end = $start + $gridSize;
+        $lineStart = $start + 1;
+        $lineEnd = $end - 2;
+        $fontSize = floor($boxSize/2) - 4;
+        $fdx = floor(($boxSize - imagefontwidth($fontSize)) / 2);
+        $fdy = ceil(($boxSize - imagefontheight($fontSize)) / 2) - 1;
+        $fontColor = $emptyBoxBC;
+        for ($i = $start + $boxSize; $i < $end - $boxSize; $i += $boxSize) {
+            ImageLine($thumbnail,  $lineStart,  $i, $lineEnd,  $i, $lighterBorder);
+            ImageLine($thumbnail,  $i,  $lineStart,  $i, $lineEnd, $lighterBorder);
+        }
+        for ($i = $start; $i < $end; $i += 3*$boxSize) {
+            ImageLine($thumbnail,  $lineStart,  $i, $lineEnd,  $i, $darkerBorder);
+            ImageLine($thumbnail,  $i,  $lineStart,  $i, $lineEnd, $darkerBorder);
+        }
+        $x = $start + 1;
+        $y = $start + 1;
+        $boxSizeMinusTwo = $boxSize - 2;
+        foreach(str_split($currentGrid) as $i => $value) {
+            if ($value == UNKNOWN) {
+                $bgColor = $emptyBoxBC;
+            } else {
+                $bgColor = $clueBC;
+            }
+            imagefilledrectangle($thumbnail, $x, $y, $x+$boxSizeMinusTwo, $y+$boxSizeMinusTwo, $bgColor);
+            if ($value != UNKNOWN) imagestring($thumbnail, $fontSize, $x + $fdx, $y + $fdy, $value, $clueFC);
+            $x += $boxSize;
+            if ($i % 9 == 8) {
+                $y += $boxSize;
+                $x = $start + 1;
+            }
+        }
+    }
+    imagepng($thumbnail);
+?>
--- a/thumbnail.png
+++ b/thumbnail.png
Author	SHA1	Message	Date
Adrien MALINGREY	c477355fe9	Ajouter README.md	2025-05-21 10:38:18 +02:00
adrien	f52c970bef	meta	2025-05-09 11:50:32 +02:00
adrien	cf0a5a465e	fix	2025-05-09 11:13:29 +02:00
adrien	310a1883d2	declare properties, use session without cookies	2025-05-06 18:20:08 +02:00
adrien	4b92464c94	format	2025-05-05 23:18:26 +02:00
adrien	c09ed80a52	serviceWorker in html	2024-05-12 11:17:03 +02:00
adrien	b145ae566a	hover	2024-04-09 01:38:42 +02:00
adrien	21e8f4134f	auto import	2023-12-23 13:25:04 +01:00
adrien	31a40a7e93	format	2023-12-23 13:24:44 +01:00
adrien	ad3992ac30	navbar	2023-12-23 13:24:22 +01:00
adrien	5feaa65955	global $sudokuGridSolutions	2023-12-23 13:24:12 +01:00
adrien	ed5795a6cc	save directly nbsolutions in $_SESSION	2023-12-12 18:36:37 +01:00
adrien	bdb1a094c3	back to bootstrap dark	2023-12-11 09:13:35 +01:00
adrien	85efaca248	color: inherit	2023-12-08 01:17:20 +01:00
adrien	39c564fb89	$_SESSION["sudokuGridSolutions"]	2023-12-08 01:17:06 +01:00
adrien	ba07a531d0	save nbSolutions in session	2023-12-06 15:10:06 +01:00
adrien	f510310549	use bootstrap default color theme switcher	2023-12-06 12:08:45 +01:00
adrien	5091e6a888	update 400.php style	2023-12-06 11:02:46 +01:00
adrien	67cd3594a6	fix context-menu z-index	2023-12-06 10:38:57 +01:00
adrien	4027a8b36f	md	2023-12-05 17:36:00 +01:00
adrien	e1fc974372	links on aside	2023-12-05 17:32:40 +01:00
adrien	853d93f8ff	fixes	2023-11-25 22:38:03 +01:00
adrien	ddc1a51899	sight fixes	2023-11-25 22:37:44 +01:00
adrien	77886a6878	fix area on showDuplicates	2023-11-25 21:51:56 +01:00
adrien	80bc9f083d	refactor with bind	2023-11-25 21:40:35 +01:00
adrien	1365ef65dd	optimize with sort	2023-11-25 19:55:59 +01:00
adrien	ad414d0da8	refactor	2023-11-25 19:03:21 +01:00
adrien	57d06c3b53	fix check on onpopstate	2023-11-25 18:47:11 +01:00
adrien	84d9222a1c	undo button is back	2023-11-25 11:58:18 +01:00
adrien	fa979cb973	use window.history	2023-11-25 04:40:40 +01:00
adrien	7245e0f073	ternary accessKeyModifiers	2023-11-02 10:37:07 +01:00
adrien	2429845dd6	navigator.platform is depreciated	2023-11-02 10:28:39 +01:00
adrien	956966fbe9	html format	2023-11-02 08:45:59 +01:00
adrien	ddcabbdd39	html format	2023-11-02 08:40:13 +01:00
adrien	743f7fa72d	format	2023-10-31 03:29:02 +01:00
adrien	3a243c38f0	color picker icon	2023-10-23 19:28:03 +02:00
adrien	beebb14464	improve color picker	2023-10-23 17:25:21 +02:00
adrien	24806a289f	improve color picker	2023-10-23 16:43:19 +02:00
adrien	4a0d03f445	add color picker	2023-10-23 09:16:46 +02:00
adrien	2e5125c298	uncheck radio if clicked twice	2023-10-17 23:33:39 +02:00
adrien	959deb5e14	icon margin	2023-06-21 08:38:19 +02:00
adrien	562cd7964b	negative icon margin	2023-06-21 08:25:20 +02:00
adrien	e437a01e30	more button padding	2023-06-18 12:32:00 +02:00
adrien	f811000ea0	less button padding	2023-06-18 12:08:43 +02:00
adrien	35f1bee053	update thumbnail	2023-04-30 10:59:58 +02:00
adrien	79a20f323a	update manifest	2023-04-30 10:27:41 +02:00
adrien	e80fef6c08	force favicon and manifest reload	2023-04-30 03:43:18 +02:00
adrien	7c65480bdd	CDN	2023-04-22 16:14:46 +02:00
adrien	7043fb8bb6	CDN	2023-04-22 16:09:00 +02:00
adrien	15ed790caf	smartphone friendly	2023-04-21 03:40:11 +02:00
adrien	c0c815e757	new thumbnail	2023-04-21 01:53:16 +02:00
adrien	5bd46082d5	move insertRadio0	2023-04-16 16:11:09 +02:00
adrien	de7b013716	text cursor	2023-04-16 15:14:08 +02:00
adrien	dab898c391	focus	2023-04-16 03:37:24 +02:00
adrien	f53e09b52e	remix icons	2023-04-16 03:36:30 +02:00
adrien	176e72c465	small changes	2023-04-05 21:54:42 +02:00
adrien	cedd63dd90	source code	2023-03-31 02:33:57 +02:00
adrien	60b5f74e94	restart on no hash	2023-03-31 02:22:07 +02:00
adrien	c47cd498c0	fix onhashchange	2023-03-31 02:15:39 +02:00
adrien	6ee740cebd	onhashchange	2023-03-31 01:55:12 +02:00
adrien	785f1460fb	save to location.hash	2023-03-31 01:47:22 +02:00
adrien	80fa25c092	fix disable insertRadio	2023-03-31 01:35:47 +02:00
adrien	ac91453013	table-success	2023-03-30 21:26:14 +02:00
adrien	8c62d6bb0e	text insert radio to the right	2023-03-30 19:38:36 +02:00
adrien	8f412bdd0f	keyboard button	2023-03-30 03:42:32 +02:00
adrien	dee27c9ca7	ui	2023-03-30 02:55:15 +02:00
adrien	0f83b8de42	Merge branch 'master' of https://git.malingrey.fr/adrien/sudoku	2023-03-30 02:23:06 +02:00
adrien	ab11f85215	add sight function	2023-03-30 02:22:59 +02:00
adrien	9191b6836c	fix insertRadio filter	2023-03-30 01:21:34 +02:00
adrien	b5345e1a4d	optimize	2023-03-30 01:12:02 +02:00
adrien	fa970170d4	bootstrap css	2023-03-29 23:28:48 +02:00
adrien	573608b63c	alternate stylesheet	2021-11-08 19:19:27 +01:00
adrien	ca22cb129d	V2.8	2021-04-17 15:55:41 +02:00
adrien	80d368446a	Merge branch 'master' of https://git.malingrey.fr/adrien/sudoku	2020-11-23 00:02:44 +01:00
adrien	f7d6dbf3f3	save at will, not automatically	2020-11-23 00:02:12 +01:00
adrien	cfc535b772	save at will (not automatically)	2020-11-22 23:53:57 +01:00
adrien	019ce058cd	small changes	2020-11-18 02:59:18 +01:00
adrien	a75b898ea6	little enhancements	2020-11-16 20:21:30 +01:00
adrien	cd22ded40e	show same value even when highlight disabled	2020-11-16 03:45:37 +01:00
adrien	5836f53a24	manage url args	2020-11-14 12:45:49 +01:00
adrien	9b2f1f9d78	freeze grid, fix containsDuplicates	2020-11-14 01:24:43 +01:00
adrien	3b8e9b85ea	fixes	2020-11-14 00:41:03 +01:00
adrien	8121768fe4	rename to .php	2020-11-14 00:00:44 +01:00
adrien	e1cd9ca1a2	check unknown grid	2020-11-13 21:08:04 +01:00
adrien	58c50f0e1d	php session	2020-11-13 13:10:56 +01:00
adrien	bda833f6e3	404!	2020-11-13 05:08:21 +01:00
adrien	df2bfa1333	show when no candidates	2020-11-13 02:55:51 +01:00
adrien	c09d51555d	automatically insert only candidate on click	2020-11-13 02:12:58 +01:00
adrien	b20c6b72bd	PWA saves curent grid for when offline	2020-11-13 01:40:29 +01:00
adrien	576cd3619f	cursors!	2020-11-11 05:25:40 +01:00
adrien	d84d77e083	code cleanup	2020-11-09 17:37:29 +01:00
adrien	a475c7fbf3	style cursor on tool selected	2020-11-09 13:20:10 +01:00
adrien	2ac980bb82	use input radio and checkbox instead of buttons	2020-11-09 12:30:14 +01:00
adrien	ccb8e91728	fix undo	2020-11-09 02:19:25 +01:00
adrien	ef758fac04	write values on click, choose highlighting, svg icons	2020-11-09 01:24:09 +01:00
adrien	d5655b7a9a	fix context menu input	2020-11-03 13:34:30 +01:00
adrien	e23dfc9f7f	web app	2020-11-02 21:12:43 +01:00
adrien	1826e1e671	more readable colors	2020-10-30 20:00:57 +01:00
adrien	2fe57eeab4	save game	2020-10-30 19:47:01 +01:00
adrien	8295fed903	generate favicon	2020-10-30 19:44:22 +01:00