// 3D First Person Game with Physics and Interactions
document.addEventListener('DOMContentLoaded', () => {
    const canvas = document.getElementById('gameCanvas');
    const gl = canvas.getContext('webgl') || canvas.getContext('experimental-webgl');
    
    if (!gl) {
        alert('WebGL not supported in your browser!');
        return;
    }

    // Set canvas to full window size
    canvas.width = window.innerWidth;
    canvas.height = window.innerHeight;

    // Camera settings
    const camera = {
        position: [0, 1.6, 5],
        rotation: [0, 0, 0],
        fov: 75,
        near: 0.1,
        far: 1000,
        speed: 0.2,
        height: 1.6
    };

    // Game state
    const game = {
        score: 0,
        collectedItems: 0,
        maxItems: 10,
        isRunning: true,
        startTime: Date.now()
    };
// Player movement state
    const movement = {
        forward: false,
        backward: false,
        left: false,
        right: false,
        jump: false,
        isGrounded: false,
        velocityY: 0,
        gravity: -0.005
    };

    // Physics settings
    const physics = {
        friction: 0.98,
        maxSpeed: 0.3,
        jumpForce: 0.15
    };
    // Game controls
    let isMouseLocked = false;
    let mouseSensitivity = 0.002;
    const raycaster = new THREE.Raycaster();
    const pointer = new THREE.Vector2();
// Initialize scene
    const scene = new THREE.Scene();
    const renderer = new THREE.WebGLRenderer({ canvas, antialias: true });
    renderer.setSize(canvas.width, canvas.height);
    renderer.setClearColor(0x222222);

    // Camera (using Three.js PerspectiveCamera)
    const threeCamera = new THREE.PerspectiveCamera(
        camera.fov,
        canvas.width / canvas.height,
        camera.near,
        camera.far
    );
    threeCamera.position.set(...camera.position);
    // Enhanced lighting
    const ambientLight = new THREE.AmbientLight(0x404040, 0.5);
    scene.add(ambientLight);
    
    const directionalLight = new THREE.DirectionalLight(0xffffff, 0.8);
    directionalLight.position.set(1, 5, 1);
    directionalLight.castShadow = true;
    directionalLight.shadow.mapSize.width = 2048;
    directionalLight.shadow.mapSize.height = 2048;
    scene.add(directionalLight);

    // Hemisphere light for natural outdoor lighting
    const hemiLight = new THREE.HemisphereLight(0xffffbb, 0x080820, 0.5);
    scene.add(hemiLight);

    // Fog for depth
    scene.fog = new THREE.FogExp2(0x222222, 0.02);
// Create a simple maze environment
    createEnvironment(scene);

    // Event listeners for keyboard
    // Enhanced controls with jump
    window.addEventListener('keydown', (e) => {
        switch (e.key.toLowerCase()) {
            case 'w': movement.forward = true; break;
            case 's': movement.backward = true; break;
            case 'a': movement.left = true; break;
            case 'd': movement.right = true; break;
            case ' ': 
                if (movement.isGrounded) {
                    movement.jump = true;
                    movement.isGrounded = false;
                    movement.velocityY = physics.jumpForce;
                }
                break;
            case 'e': checkInteraction(); break;
        }
    });
    window.addEventListener('keyup', (e) => {
        switch (e.key.toLowerCase()) {
            case 'w': movement.forward = false; break;
            case 's': movement.backward = false; break;
            case 'a': movement.left = false; break;
            case 'd': movement.right = false; break;
            case ' ': movement.jump = false; break;
        }
    });
// Mouse movement controls
    canvas.addEventListener('click', () => {
        canvas.requestPointerLock = canvas.requestPointerLock || 
                                   canvas.mozRequestPointerLock || 
                                   canvas.webkitRequestPointerLock;
        canvas.requestPointerLock();
    });

    document.addEventListener('pointerlockchange', lockChangeAlert, false);
    document.addEventListener('mozpointerlockchange', lockChangeAlert, false);

    function lockChangeAlert() {
        isMouseLocked = document.pointerLockElement === canvas || 
                       document.mozPointerLockElement === canvas;
    }

    document.addEventListener('mousemove', (e) => {
        if (!isMouseLocked) return;
        
        camera.rotation[1] -= e.movementX * mouseSensitivity;
        camera.rotation[0] = Math.max(-Math.PI/2.5, Math.min(Math.PI/2.5, 
            camera.rotation[0] - e.movementY * mouseSensitivity
        ));
    });

    // Handle window resize
    window.addEventListener('resize', () => {
        canvas.width = window.innerWidth;
        canvas.height = window.innerHeight;
        threeCamera.aspect = canvas.width / canvas.height;
        threeCamera.updateProjectionMatrix();
        renderer.setSize(canvas.width, canvas.height);
    });
    // Enhanced game loop with physics
    const clock = new THREE.Clock();
    function animate() {
        if (!game.isRunning) return;
        
        requestAnimationFrame(animate);
        const delta = clock.getDelta();
        
        // Movement vectors
        const forwardVector = new THREE.Vector3(
            Math.sin(camera.rotation[1]),
            0,
            Math.cos(camera.rotation[1])
        ).normalize();
        
        const sideVector = new THREE.Vector3(
            Math.sin(camera.rotation[1] + Math.PI/2),
            0,
            Math.cos(camera.rotation[1] + Math.PI/2)
        ).normalize();

        // Apply forces
        const velocity = new THREE.Vector3();
        
        if (movement.forward) velocity.add(forwardVector);
        if (movement.backward) velocity.sub(forwardVector);
        if (movement.left) velocity.sub(sideVector);
        if (movement.right) velocity.add(sideVector);
        
        // Apply physics
        velocity.multiplyScalar(camera.speed);
        velocity.y = movement.velocityY;
        
        // Limit speed
        if (velocity.length() > physics.maxSpeed) {
            velocity.normalize().multiplyScalar(physics.maxSpeed);
        }
        
        // Apply friction
        velocity.multiplyScalar(physics.friction);
        
        // Update position
        threeCamera.position.add(velocity);
        
        // Gravity
        if (!movement.isGrounded) {
            movement.velocityY += movement.gravity;
        } else {
            movement.velocityY = 0;
        }
        
        // Ground check
        checkGroundCollision();
        
        // Update camera rotation
        threeCamera.rotation.set(
            camera.rotation[0],
            camera.rotation[1],
            0,
            'YXZ'
        );
renderer.render(scene, threeCamera);
    }

    animate();
});
    // Create game environment with collectibles and obstacles
    function createEnvironment(scene) {
        const tileSize = 5;
        const gridSize = 11;
        const wallHeight = 3;
        
        // Floor with texture
        const floorGeometry = new THREE.PlaneGeometry(tileSize * gridSize, tileSize * gridSize);
        const floorTexture = new THREE.TextureLoader().load('https://raw.githubusercontent.com/mrdoob/three.js/dev/examples/textures/terrain/grasslight-big.jpg');
        floorTexture.wrapS = floorTexture.wrapT = THREE.RepeatWrapping;
        floorTexture.repeat.set(gridSize, gridSize);
        const floorMaterial = new THREE.MeshStandardMaterial({ 
            map: floorTexture,
            roughness: 0.9,
            metalness: 0
        });
        const floor = new THREE.Mesh(floorGeometry, floorMaterial);
        floor.rotation.x = -Math.PI / 2;
        floor.receiveShadow = true;
        scene.add(floor);

        // Walls with better materials
        const wallMaterial = new THREE.MeshStandardMaterial({ 
            color: 0xcccccc,
            roughness: 0.7,
            metalness: 0.1
        });
        
        // Create maze grid
        const mazeGrid = Array(gridSize).fill().map(() => Array(gridSize).fill(0));
        
        // Basic maze structure
        for (let x = 0; x < gridSize; x++) {
            for (let z = 0; z < gridSize; z++) {
                // Border walls
                if (x === 0 || x === gridSize-1 || z === 0 || z === gridSize-1) {
                    mazeGrid[x][z] = 1;
                }
                // Inner pattern
                else if (Math.random() > 0.7 && !(x === 1 && z === 1)) {
                    mazeGrid[x][z] = 1;
                }
            }
        }
        
        // Ensure there's always a path
        mazeGrid[1][1] = 0;  // Start position
        mazeGrid[gridSize-2][gridSize-2] = 0;  // Exit position
        // Build maze from grid
        for (let x = 0; x < gridSize; x++) {
            for (let z = 0; z < gridSize; z++) {
                if (mazeGrid[x][z]) {
                    const wallX = (x - (gridSize-1)/2) * tileSize;
                    const wallZ = (z - (gridSize-1)/2) * tileSize;
                    
                    const wallGeometry = new THREE.BoxGeometry(
                        tileSize, wallHeight, tileSize
                    );
                    const wallMesh = new THREE.Mesh(wallGeometry, wallMaterial);
                    wallMesh.position.set(wallX, wallHeight/2, wallZ);
                    wallMesh.castShadow = true;
                    wallMesh.receiveShadow = true;
                    scene.add(wallMesh);
                }
            }
        }
walls.forEach(wall => {
        const wallGeometry = new THREE.BoxGeometry(...wall.size);
        const wallMesh = new THREE.Mesh(wallGeometry, wallMaterial);
        wallMesh.position.set(...wall.position);
        scene.add(wallMesh);
    });
        // Create collectible items
        for (let i = 0; i < game.maxItems; i++) {
            let x, z;
            do {
                x = Math.floor(Math.random() * gridSize);
                z = Math.floor(Math.random() * gridSize);
            } while (mazeGrid[x][z] || (x === 1 && z === 1));
            
            const itemX = (x - (gridSize-1)/2) * tileSize;
            const itemZ = (z - (gridSize-1)/2) * tileSize;
            
            const itemGeometry = new THREE.SphereGeometry(0.5, 16, 16);
            const itemMaterial = new THREE.MeshStandardMaterial({ 
                color: 0x00ff00,
                emissive: 0x00ff00,
                emissiveIntensity: 0.5,
                metalness: 0.3,
                roughness: 0.4
            });
            const item = new THREE.Mesh(itemGeometry, itemMaterial);
            item.position.set(itemX, 1, itemZ);
            item.userData.isCollectible = true;
            item.castShadow = true;
            scene.add(item);
        }
        
        // Create exit door
        const exitX = ((gridSize-2) - (gridSize-1)/2) * tileSize;
        const exitZ = ((gridSize-2) - (gridSize-1)/2) * tileSize;
        
        const exitGeometry = new THREE.BoxGeometry(tileSize/2, wallHeight/2, tileSize/2);
        const exitMaterial = new THREE.MeshStandardMaterial({
            color: 0xff0000,
            emissive: 0xff0000,
            emissiveIntensity: 0.3
        });
        const exit = new THREE.Mesh(exitGeometry, exitMaterial);
        exit.position.set(exitX, wallHeight/4, exitZ);
        exit.userData.isExit = true;
        scene.add(exit);
}
    // Collision detection
    function checkGroundCollision() {
        const groundRay = new THREE.Raycaster(
            threeCamera.position,
            new THREE.Vector3(0, -1, 0),
            0,
            camera.height * 1.1
        );
        
        const intersects = groundRay.intersectObjects(scene.children.filter(obj => obj !== floor));
        movement.isGrounded = intersects.length > 0;
    }

    // Interaction system
    function checkInteraction() {
        raycaster.setFromCamera(pointer, threeCamera);
        const intersects = raycaster.intersectObjects(scene.children);
        
        if (intersects.length > 0) {
            const obj = intersects[0].object;
            
            if (obj.userData.isCollectible) {
                // Collect item
                scene.remove(obj);
                game.collectedItems++;
                game.score += 100;
                updateUI();
                
                if (game.collectedItems === game.maxItems) {
                    document.getElementById('hint').textContent = "Find the red exit!";
                }
            } else if (obj.userData.isExit && game.collectedItems === game.maxItems) {
                // Game completed
                game.isRunning = false;
                const timeElapsed = Math.floor((Date.now() - game.startTime) / 1000);
                document.getElementById('title').innerHTML = `
                    <h1 class="text-xl font-bold">Game Completed!</h1>
                    <p>Score: ${game.score + timeElapsed * 10}</p>
                    <p>Time: ${timeElapsed}s</p>
                `;
            }
        }
    }

    // UI update
    function updateUI() {
        document.getElementById('score').textContent = `Score: ${game.score}`;
        document.getElementById('items').textContent = `Items: ${game.collectedItems}/${game.maxItems}`;
    }

    // Initialize UI elements
    const ui = document.getElementById('ui');
    const gameInfo = document.createElement('div');
    gameInfo.id = 'game-info';
    gameInfo.style.position = 'absolute';
    gameInfo.style.top = '20px';
    gameInfo.style.right = '20px';
    gameInfo.style.backgroundColor = 'rgba(0,0,0,0.5)';
    gameInfo.style.padding = '10px';
    gameInfo.style.borderRadius = '5px';
    gameInfo.style.color = 'white';
    gameInfo.innerHTML = `
        <div id="score">Score: 0</div>
        <div id="items">Items: 0/${game.maxItems}</div>
        <div id="hint">Collect all green spheres!</div>
    `;
    ui.appendChild(gameInfo);

// Include Three.js and PointerLockControls from CDN
const threeScript = document.createElement('script');
threeScript.src = 'https://cdn.jsdelivr.net/npm/three@0.132.2/build/three.min.js';
document.head.appendChild(threeScript);

const pointerLockScript = document.createElement('script');
pointerLockScript.src = 'https://cdn.jsdelivr.net/npm/three@0.132.2/examples/js/controls/PointerLockControls.js';
document.head.appendChild(pointerLockScript);