document.addEventListener('DOMContentLoaded', () => {
    // --- Get Elements ---
    const gridContainer = document.getElementById('grid-container');
    const targetCoordsDisplay = document.getElementById('target-coords');
    const feedbackDisplay = document.getElementById('feedback');
    const itemNameDisplay = document.getElementById('item-name');
    const yAxisLabelsContainer = document.getElementById('y-axis-labels');
    const xAxisLabelsContainer = document.getElementById('x-axis-labels');
    const xAxisContainer = document.getElementById('x-axis-container');
    const scoreDisplay = document.getElementById('score-display');

    // --- Game Settings ---
    const gridSize = 8;
    const cellSize = 40; // Pixels

    // --- Items to Find ---
    const itemsToFind = [
        { name: "a sparkling diamond", emoji: "💎" }, { name: "a red apple", emoji: "🍎" },
        { name: "a yummy pizza slice", emoji: "🍕" }, { name: "a fast rocket", emoji: "🚀" },
        { name: "a cute puppy", emoji: "🐶" }, { name: "a bright star", emoji: "⭐" },
        { name: "a cool robot", emoji: "🤖" }, { name: "a friendly ghost", emoji: "👻" },
        { name: "a birthday cake", emoji: "🎂" }, { name: "a magical unicorn", emoji: "🦄" }
    ];
    const totalItems = itemsToFind.length;

    // --- Game State ---
    let targetX = -1;
    let targetY = -1;
    let currentItemIndex = 0;
    let foundCurrent = false;
    let score = 0;

    // --- Initialize Grid and Axes ---
    function initializeGameArea() {
        gridContainer.innerHTML = '';
        xAxisLabelsContainer.innerHTML = '';
        yAxisLabelsContainer.innerHTML = '';
        score = 0;
        currentItemIndex = 0;
        updateScoreDisplay();

        // CSS variable for reference if needed, though direct style is used now
        document.documentElement.style.setProperty('--cell-size', `${cellSize}px`);

        const gridTotalSize = gridSize * cellSize;
        const yAxisWidth = 20; // Must match CSS .y-axis-label width
        const yAxisMargin = 5; // Must match CSS #y-axis-labels margin-right

        // --- Configure Grid Container Styles Explicitly ---
        gridContainer.style.width = `${gridTotalSize}px`;
        gridContainer.style.height = `${gridTotalSize}px`;
        gridContainer.style.display = 'grid'; // **Ensure grid layout**
        gridContainer.style.gridTemplateColumns = `repeat(${gridSize}, ${cellSize}px)`; // **Ensure columns**
        gridContainer.style.gridTemplateRows = `repeat(${gridSize}, ${cellSize}px)`; // **Ensure rows**
        // ---

        // Configure Axis Containers
        yAxisLabelsContainer.style.height = `${gridTotalSize}px`; // Match grid height
        xAxisLabelsContainer.style.width = `${gridTotalSize}px`; // Inner label container matches grid width
        xAxisContainer.style.width = `${yAxisWidth + yAxisMargin + gridTotalSize}px`; // Outer width includes Y-axis space
        xAxisLabelsContainer.style.marginLeft = `${yAxisWidth + yAxisMargin}px`; // Align labels under grid

        // Create Y-axis labels (1 to N, bottom-up visually)
        for (let y = 1; y <= gridSize; y++) {
            const label = document.createElement('div');
            label.classList.add('axis-label', 'y-axis-label');
            label.textContent = y;
            label.style.height = `${cellSize}px`;
            yAxisLabelsContainer.appendChild(label);
        }

        // Create X-axis labels (1 to N, left-to-right)
        for (let x = 1; x <= gridSize; x++) {
            const label = document.createElement('div');
            label.classList.add('axis-label', 'x-axis-label');
            label.textContent = x;
            label.style.width = `${cellSize}px`;
            xAxisLabelsContainer.appendChild(label);
        }

        // Create grid cells
        // Loop Y from gridSize down to 1 so that Y=1 is the bottom row visually
        for (let y = gridSize; y >= 1; y--) {
            // Loop X from 1 to gridSize as usual (left-to-right)
            for (let x = 1; x <= gridSize; x++) {
                const cell = document.createElement('div');
                cell.classList.add('grid-cell');
                cell.dataset.x = x; // Store correct X coordinate
                cell.dataset.y = y; // Store correct Y coordinate
                cell.style.width = `${cellSize}px`; // Explicit size
                cell.style.height = `${cellSize}px`; // Explicit size
                cell.addEventListener('click', handleCellClick);
                gridContainer.appendChild(cell);
            }
        }
        console.log("Grid, Axes, and Score Initialized.");
    }

     // --- Update Score Display ---
     function updateScoreDisplay() {
        scoreDisplay.textContent = `Score: ${score} / ${totalItems}`;
    }

    // --- Set a New Target Item and Location ---
    function setNewTarget() {
        foundCurrent = false;

        // --- Game Over Check ---
        if (currentItemIndex >= totalItems) {
            let finalMessage = `All done! Your final score: ${score} / ${totalItems}! 🎉`;
            if (score === totalItems) {
                finalMessage += " Perfect score! 🥳";
            } else if (score >= totalItems / 2) {
                finalMessage += " Great job! 👍";
            }
            feedbackDisplay.textContent = finalMessage;
            feedbackDisplay.className = 'correct-feedback';
            targetCoordsDisplay.textContent = "(✔,✔)";
            itemNameDisplay.textContent = 'all the items';
            // Optional: Add a visible reset button here instead of forcing refresh
            return;
        }

        const currentItem = itemsToFind[currentItemIndex];

        // --- Find Empty Cell for New Target ---
        let newTargetFound = false;
        let attempts = 0; // Prevent infinite loop
        const maxAttempts = gridSize * gridSize * 2; // Generous limit

        while (!newTargetFound && attempts < maxAttempts) {
            targetX = Math.floor(Math.random() * gridSize) + 1;
            targetY = Math.floor(Math.random() * gridSize) + 1;
            const potentialCell = gridContainer.querySelector(`.grid-cell[data-x="${targetX}"][data-y="${targetY}"]`);

            // Check if the cell exists AND is visually empty (no emoji)
            if (potentialCell && potentialCell.textContent.trim() === '') {
                newTargetFound = true;
            }
            attempts++;
        }

        // Handle unlikely case where no empty cell is found
        if (!newTargetFound) {
             console.error("Could not find an empty cell for the next target!");
             feedbackDisplay.textContent = "Uh oh, the map is full! Please refresh.";
             return;
         }

        // --- Update Display ---
        itemNameDisplay.textContent = currentItem.name;
        targetCoordsDisplay.textContent = `(${targetX}, ${targetY})`;
        feedbackDisplay.textContent = `Where is ${currentItem.name}? (${currentItemIndex + 1}/${totalItems})`;
        feedbackDisplay.className = '';

        // Reset temporary styles from previous round
        document.querySelectorAll('.grid-cell').forEach(cell => {
            cell.classList.remove('just-found', 'incorrect');
        });
        console.log(`Round ${currentItemIndex + 1}: Find ${currentItem.name} at (${targetX}, ${targetY})`);
    }

    // --- Handle Cell Click ---
    function handleCellClick(event) {
        // Prevent action if round/game is over or cell already found
        if (foundCurrent || currentItemIndex >= totalItems) return;

        const clickedCell = event.target;
        if (clickedCell.classList.contains('found-item')) return;

        const clickedX = parseInt(clickedCell.dataset.x);
        const clickedY = parseInt(clickedCell.dataset.y);

        // Clear any lingering incorrect styles
        document.querySelectorAll('.grid-cell.incorrect').forEach(cell => {
            cell.classList.remove('incorrect');
        });

        // --- Check if Correct ---
        if (clickedX === targetX && clickedY === targetY) {
            foundCurrent = true;
            score++;
            updateScoreDisplay();

            const currentItem = itemsToFind[currentItemIndex];

            feedbackDisplay.textContent = `You found ${currentItem.name}! 👍`;
            feedbackDisplay.className = 'correct-feedback';

            clickedCell.textContent = currentItem.emoji; // Add emoji
            clickedCell.classList.add('just-found'); // Temporary highlight

            // After highlight animation, switch to permanent 'found' style
            setTimeout(() => {
                clickedCell.classList.remove('just-found');
                clickedCell.classList.add('found-item');
            }, 600); // Duration should be >= pulse animation time

            currentItemIndex++; // Move to next item

            setTimeout(setNewTarget, 1800); // Delay before next target

        } else {
            // --- Incorrect Guess ---
            feedbackDisplay.textContent = "Not quite! Try again. 🤔";
            feedbackDisplay.className = 'incorrect-feedback';
            clickedCell.classList.add('incorrect');

            // Remove incorrect style after shake animation
            setTimeout(() => {
                // Check if still marked incorrect (user might click fast)
                if (clickedCell.classList.contains('incorrect')) {
                    clickedCell.classList.remove('incorrect');
                }
            }, 500); // Match shake animation duration
        }
    }

    // --- Start the Game ---
    initializeGameArea();
    setNewTarget();

}); // End DOMContentLoaded