import * as THREE from 'three';
import * as CANNON from 'cannon-es';
// import { OrbitControls } from 'three/addons/controls/OrbitControls.js'; // Optional for debugging

// --- DOM Elements ---
const sceneContainer = document.getElementById('scene-container');
const statsElement = document.getElementById('stats-display');
const inventoryElement = document.getElementById('inventory-display');
const logElement = document.getElementById('log-display');

// --- Config ---
const ROOM_SIZE = 10;
const WALL_HEIGHT = 4;
const WALL_THICKNESS = 0.5;
const CAMERA_Y_OFFSET = 15; // Camera height
const PLAYER_SPEED = 5; // Movement speed units/sec
const PLAYER_RADIUS = 0.5;
const PLAYER_HEIGHT = 1.8;
const PROJECTILE_SPEED = 15;
const PROJECTILE_RADIUS = 0.2;

// --- Three.js Setup ---
let scene, camera, renderer;
let playerMesh; // Visual representation of the player
const meshesToSync = []; // Array to hold { mesh, body } pairs for sync
const projectiles = []; // Active projectiles { mesh, body, lifetime }

// --- Physics Setup ---
let world;
let playerBody; // Physics body for the player
const physicsBodies = []; // Keep track of bodies to remove later if needed
const cannonDebugRenderer = null; // Optional: Use cannon-es-debugger

// --- Game State ---
let gameState = {
    inventory: [],
    stats: { hp: 30, maxHp: 30, strength: 7, wisdom: 5, courage: 6 },
    position: { x: 0, z: 0 }, // Player's logical grid position (optional)
    monsters: [], // Store active monster data { id, hp, body, mesh, ... }
    items: [], // Store active item data { id, name, body, mesh, ... }
};
const keysPressed = {}; // Track currently pressed keys

// --- Game Data (Keep relevant parts, add monster/item placements) ---
const gameData = {
    // Structure: "x,y": { type, features, items?, monsters? }
    "0,0": { type: 'city', features: ['door_north'] },
    "0,1": { type: 'forest', features: ['path_north', 'door_south', 'item_potion'] }, // Add item marker
    "0,2": { type: 'forest', features: ['path_south', 'monster_goblin'] }, // Add monster marker
    // ... Add many more locations based on your design ...
};

const itemsData = {
    "Healing Potion": { type: "consumable", description: "Restores 10 HP.", hpRestore: 10, model: 'sphere_red' },
    "Key": { type: "quest", description: "Unlocks a door.", model: 'box_gold'},
    // ...
};

const monstersData = {
    "goblin": { hp: 15, attack: 4, defense: 1, speed: 2, model: 'capsule_green', xp: 5 },
    // ...
};

// --- Initialization ---

function init() {
    initThreeJS();
    initPhysics();
    initPlayer();
    generateMap(); // Generate based on gameData
    setupInputListeners();
    animate(); // Start the game loop
    updateUI(); // Initial UI update
    addLog("Welcome! Move with WASD/Arrows. Space to Attack.", "info");
}

function initThreeJS() {
    scene = new THREE.Scene();
    scene.background = new THREE.Color(0x111111);

    camera = new THREE.PerspectiveCamera(60, sceneContainer.clientWidth / sceneContainer.clientHeight, 0.1, 1000);
    // Start camera slightly offset, will follow player
    camera.position.set(0, CAMERA_Y_OFFSET, 5); // Look slightly forward initially
    camera.lookAt(0, 0, 0);

    renderer = new THREE.WebGLRenderer({ antialias: true });
    renderer.setSize(sceneContainer.clientWidth, sceneContainer.clientHeight);
    renderer.shadowMap.enabled = true;
    sceneContainer.appendChild(renderer.domElement);

    // Lighting
    const ambientLight = new THREE.AmbientLight(0xffffff, 0.4);
    scene.add(ambientLight);
    const dirLight = new THREE.DirectionalLight(0xffffff, 0.8);
    dirLight.position.set(10, 20, 5);
    dirLight.castShadow = true; // Enable shadows for this light
    scene.add(dirLight);

    // Configure shadow properties if needed
    dirLight.shadow.mapSize.width = 1024;
    dirLight.shadow.mapSize.height = 1024;

    window.addEventListener('resize', onWindowResize, false);
}

function initPhysics() {
    world = new CANNON.World({
        gravity: new CANNON.Vec3(0, -9.82, 0) // Standard gravity
    });
    world.broadphase = new CANNON.NaiveBroadphase(); // Simple broadphase for now
    // world.solver.iterations = 10; // Adjust solver iterations if needed

    // Ground plane (physics only)
    const groundShape = new CANNON.Plane();
    const groundBody = new CANNON.Body({ mass: 0 }); // Mass 0 means static
    groundBody.addShape(groundShape);
    groundBody.quaternion.setFromEuler(-Math.PI / 2, 0, 0); // Rotate plane to be horizontal
    world.addBody(groundBody);
}

// --- Primitive Assembly Functions ---
function createPlayerMesh() {
    const group = new THREE.Group();
    // Simple capsule: cylinder + sphere cap
    const bodyMat = new THREE.MeshLambertMaterial({ color: 0x0077ff }); // Blue player
    const bodyGeom = new THREE.CylinderGeometry(PLAYER_RADIUS, PLAYER_RADIUS, PLAYER_HEIGHT - (PLAYER_RADIUS * 2), 16);
    const body = new THREE.Mesh(bodyGeom, bodyMat);
    body.position.y = PLAYER_RADIUS; // Position cylinder part correctly
    body.castShadow = true;

    const headGeom = new THREE.SphereGeometry(PLAYER_RADIUS, 16, 16);
    const head = new THREE.Mesh(headGeom, bodyMat);
    head.position.y = PLAYER_HEIGHT - PLAYER_RADIUS; // Position head on top
    head.castShadow = true;

    group.add(body);
    group.add(head);

    // Add a "front" indicator (e.g., small cone)
    const noseGeom = new THREE.ConeGeometry(PLAYER_RADIUS * 0.3, PLAYER_RADIUS * 0.5, 8);
    const noseMat = new THREE.MeshBasicMaterial({ color: 0xffff00 }); // Yellow nose
    const nose = new THREE.Mesh(noseGeom, noseMat);
    nose.position.set(0, PLAYER_HEIGHT * 0.7, PLAYER_RADIUS * 0.7); // Position in front, slightly down
    nose.rotation.x = Math.PI / 2; // Point forward
    group.add(nose);

    return group;
}

function createSimpleMonsterMesh(modelType = 'capsule_green') {
    const group = new THREE.Group();
    let color = 0xff0000; // Default red
    let geom;
    let mat;

    if (modelType === 'capsule_green') {
        color = 0x00ff00; // Green
        mat = new THREE.MeshLambertMaterial({ color: color });
        const bodyGeom = new THREE.CylinderGeometry(0.4, 0.4, 1.0, 12);
        const headGeom = new THREE.SphereGeometry(0.4, 12, 12);
        const body = new THREE.Mesh(bodyGeom, mat);
        const head = new THREE.Mesh(headGeom, mat);
        body.position.y = 0.5;
        head.position.y = 1.0 + 0.4;
        group.add(body);
        group.add(head);
    } else { // Default box monster
        geom = new THREE.BoxGeometry(0.8, 1.2, 0.8);
        mat = new THREE.MeshLambertMaterial({ color: color });
        const mesh = new THREE.Mesh(geom, mat);
        mesh.position.y = 0.6;
        group.add(mesh);
    }
    group.traverse(child => { if (child.isMesh) child.castShadow = true; });
    return group;
}

function createSimpleItemMesh(modelType = 'sphere_red') {
     let geom, mat;
     let color = 0xffffff; // Default white

     if(modelType === 'sphere_red') {
         color = 0xff0000;
         geom = new THREE.SphereGeometry(0.3, 16, 16);
     } else if (modelType === 'box_gold') {
          color = 0xffd700;
          geom = new THREE.BoxGeometry(0.4, 0.4, 0.4);
     } else { // Default sphere
          geom = new THREE.SphereGeometry(0.3, 16, 16);
     }
     mat = new THREE.MeshStandardMaterial({ color: color, metalness: 0.3, roughness: 0.6 });
     const mesh = new THREE.Mesh(geom, mat);
     mesh.position.y = PLAYER_RADIUS; // Place at player radius height
     mesh.castShadow = true;
     return mesh;
}

function createProjectileMesh() {
    const geom = new THREE.SphereGeometry(PROJECTILE_RADIUS, 8, 8);
    const mat = new THREE.MeshBasicMaterial({ color: 0xffff00 }); // Bright yellow
    const mesh = new THREE.Mesh(geom, mat);
    return mesh;
}

// --- Player Setup ---
function initPlayer() {
    // Visuals
    playerMesh = createPlayerMesh();
    playerMesh.position.y = PLAYER_HEIGHT / 2; // Adjust initial position based on model
    scene.add(playerMesh);

    // Physics
    // Using a capsule shape approximation (sphere + cylinder + sphere) is complex in Cannon.
    // Let's use a simpler Sphere or Box for now. Sphere is often better for rolling/movement.
    const playerShape = new CANNON.Sphere(PLAYER_RADIUS);
    playerBody = new CANNON.Body({
        mass: 5, // Give player some mass
        shape: playerShape,
        position: new CANNON.Vec3(0, PLAYER_HEIGHT / 2, 0), // Start at origin, slightly above ground
        linearDamping: 0.9, // Add damping to prevent sliding forever
        angularDamping: 0.9, // Prevent spinning wildly
        fixedRotation: true, // Prevent player body from tipping over (optional but good for top-down)
    });
     playerBody.addEventListener("collide", handlePlayerCollision); // Add collision listener
    world.addBody(playerBody);

    // Add to sync list
    meshesToSync.push({ mesh: playerMesh, body: playerBody });
}

// --- Map Generation ---
function generateMap() {
    const wallMaterial = new CANNON.Material("wallMaterial"); // For physics interactions

    for (const coordString in gameData) {
        const [xStr, yStr] = coordString.split(',');
        const x = parseInt(xStr);
        const y = parseInt(yStr); // Represents Z in 3D
        const data = gameData[coordString];

        // Create Floor Mesh (visual only, physics ground plane handles floor collision)
        const floorMesh = createFloor(data.type, x, y);
        scene.add(floorMesh); // Add floor directly to scene, not mapGroup if physics handles it

        // Create Wall Meshes and Physics Bodies
        const features = data.features || [];
        const wallPositions = [
            { dir: 'north', xOffset: 0, zOffset: -0.5, geom: geometries.wall },
            { dir: 'south', xOffset: 0, zOffset: 0.5, geom: geometries.wall },
            { dir: 'east', xOffset: 0.5, zOffset: 0, geom: geometries.wall_side },
            { dir: 'west', xOffset: -0.5, zOffset: 0, geom: geometries.wall_side },
        ];

        wallPositions.forEach(wp => {
            // Check if a feature indicates an opening in this direction
            const doorFeature = `door_${wp.dir}`;
            const pathFeature = `path_${wp.dir}`; // Consider paths as openings too
            if (!features.includes(doorFeature) && !features.includes(pathFeature)) {
                // Add Visual Wall Mesh
                const wallMesh = new THREE.Mesh(wp.geom, materials.wall);
                wallMesh.position.set(
                    x * ROOM_SIZE + wp.xOffset * ROOM_SIZE,
                    WALL_HEIGHT / 2,
                    y * ROOM_SIZE + wp.zOffset * ROOM_SIZE
                );
                wallMesh.castShadow = true;
                wallMesh.receiveShadow = true;
                scene.add(wallMesh); // Add walls directly to scene

                // Add Physics Wall Body
                const wallShape = new CANNON.Box(new CANNON.Vec3(
                    wp.geom.parameters.width / 2,
                    wp.geom.parameters.height / 2,
                    wp.geom.parameters.depth / 2
                ));
                const wallBody = new CANNON.Body({
                    mass: 0, // Static
                    shape: wallShape,
                    position: new CANNON.Vec3(wallMesh.position.x, wallMesh.position.y, wallMesh.position.z),
                    material: wallMaterial // Assign physics material
                });
                world.addBody(wallBody);
                physicsBodies.push(wallBody); // Keep track if needed for removal
            }
        });

        // Spawn Items
        if (data.items) {
            data.items.forEach(itemName => spawnItem(itemName, x, y));
        }
        // Spawn Monsters
         if (data.monsters) {
            data.monsters.forEach(monsterType => spawnMonster(monsterType, x, y));
         }

         // Add other features visually (rivers, etc. - physics interaction TBD)
         features.forEach(feature => {
             if (feature === 'river') {
                 const riverMesh = createFeature(feature, x, y);
                 if (riverMesh) scene.add(riverMesh);
             }
             // Handle other features
         });
    }
}

function spawnItem(itemName, gridX, gridY) {
    const itemData = itemsData[itemName];
    if (!itemData) {
        console.warn(`Item data not found for ${itemName}`);
        return;
    }

    const x = gridX * ROOM_SIZE + (Math.random() - 0.5) * (ROOM_SIZE * 0.5); // Randomize position within cell
    const z = gridY * ROOM_SIZE + (Math.random() - 0.5) * (ROOM_SIZE * 0.5);
    const y = PLAYER_RADIUS; // Place at reachable height

    // Visual Mesh
    const mesh = createSimpleItemMesh(itemData.model);
    mesh.position.set(x, y, z);
    mesh.userData = { type: 'item', name: itemName }; // Store game data on mesh
    scene.add(mesh);

    // Physics Body (Static Sensor)
    const shape = new CANNON.Sphere(0.4); // Slightly larger than visual for easier pickup
    const body = new CANNON.Body({
        mass: 0,
        isTrigger: true, // Sensor - detects collision but doesn't cause physical reaction
        shape: shape,
        position: new CANNON.Vec3(x, y, z)
    });
    body.userData = { type: 'item', name: itemName, mesh }; // Link body back to mesh
    world.addBody(body);

    gameState.items.push({ id: body.id, name: itemName, body: body, mesh: mesh });
    physicsBodies.push(body);
}

function spawnMonster(monsterType, gridX, gridY) {
     const monsterData = monstersData[monsterType];
     if (!monsterData) {
         console.warn(`Monster data not found for ${monsterType}`);
         return;
     }

     const x = gridX * ROOM_SIZE + (Math.random() - 0.5) * (ROOM_SIZE * 0.3); // Randomize position
     const z = gridY * ROOM_SIZE + (Math.random() - 0.5) * (ROOM_SIZE * 0.3);
     const y = PLAYER_HEIGHT / 2; // Start at roughly player height

     // Visual Mesh
     const mesh = createSimpleMonsterMesh(monsterData.model);
     mesh.position.set(x, y, z);
     mesh.userData = { type: 'monster', monsterType: monsterType };
     scene.add(mesh);

     // Physics Body (Dynamic)
     // Using a simple sphere collider for monsters for now
     const shape = new CANNON.Sphere(PLAYER_RADIUS * 0.8); // Slightly smaller than player
     const body = new CANNON.Body({
         mass: 10, // Give mass
         shape: shape,
         position: new CANNON.Vec3(x, y, z),
         linearDamping: 0.8,
         angularDamping: 0.9,
         fixedRotation: true, // Prevent tipping
     });
     body.userData = { type: 'monster', monsterType: monsterType, mesh: mesh, hp: monsterData.hp }; // Store HP on body userData
     world.addBody(body);

     gameState.monsters.push({ id: body.id, type: monsterType, hp: monsterData.hp, body: body, mesh: mesh });
     meshesToSync.push({ mesh: mesh, body: body }); // Add monster to sync list
     physicsBodies.push(body);
 }


// --- Input Handling ---
function setupInputListeners() {
    window.addEventListener('keydown', (event) => {
        keysPressed[event.key.toLowerCase()] = true;
         keysPressed[event.code] = true; // Also store by code (e.g., Space)
    });
    window.addEventListener('keyup', (event) => {
        keysPressed[event.key.toLowerCase()] = false;
         keysPressed[event.code] = false;
    });
}

function handleInput(deltaTime) {
    if (!playerBody) return;

    const moveDirection = new CANNON.Vec3(0, 0, 0);
    const moveSpeed = PLAYER_SPEED;

    if (keysPressed['w'] || keysPressed['arrowup']) {
        moveDirection.z = -1;
    } else if (keysPressed['s'] || keysPressed['arrowdown']) {
        moveDirection.z = 1;
    }

    if (keysPressed['a'] || keysPressed['arrowleft']) {
        moveDirection.x = -1;
    } else if (keysPressed['d'] || keysPressed['arrowright']) {
        moveDirection.x = 1;
    }

    // Normalize diagonal movement and apply speed
    if (moveDirection.lengthSquared() > 0) { // Only normalize if there's movement
        moveDirection.normalize();
        // Apply velocity directly - better for responsive character control than forces
        playerBody.velocity.x = moveDirection.x * moveSpeed;
        playerBody.velocity.z = moveDirection.z * moveSpeed;

        // Make player mesh face movement direction (optional)
         const angle = Math.atan2(moveDirection.x, moveDirection.z);
         // Smooth rotation? Lerp quaternion later. For now, direct set.
         playerMesh.quaternion.setFromAxisAngle(new THREE.Vector3(0, 1, 0), angle);

    } else {
        // If no movement keys pressed, gradually stop (handled by linearDamping)
        // Or set velocity to zero for instant stop:
        // playerBody.velocity.x = 0;
        // playerBody.velocity.z = 0;
    }

    // Handle 'Fire' (Space bar)
    if (keysPressed['space']) {
        fireProjectile();
        keysPressed['space'] = false; // Prevent holding space for continuous fire (debounce)
    }
}

// --- Combat ---
function fireProjectile() {
    if (!playerBody || !playerMesh) return;
    addLog("Pew!", "combat"); // Simple log

    // Create Mesh
    const projectileMesh = createProjectileMesh();
    // Create Physics Body
    const projectileShape = new CANNON.Sphere(PROJECTILE_RADIUS);
    const projectileBody = new CANNON.Body({
        mass: 0.1, // Very light
        shape: projectileShape,
        linearDamping: 0.01, // Minimal damping
        angularDamping: 0.01,
    });
    projectileBody.addEventListener("collide", handleProjectileCollision);

    // Calculate initial position and velocity
    // Start slightly in front of player, based on player's rotation
    const offsetDistance = PLAYER_RADIUS + PROJECTILE_RADIUS + 0.1; // Start just outside player radius
    const direction = new THREE.Vector3(0, 0, -1); // Base direction (forward Z)
    direction.applyQuaternion(playerMesh.quaternion); // Rotate based on player mesh orientation

    const startPos = new CANNON.Vec3().copy(playerBody.position).vadd(
        new CANNON.Vec3(direction.x, 0, direction.z).scale(offsetDistance) // Offset horizontally
    );
    startPos.y = PLAYER_HEIGHT * 0.7; // Fire from "head" height approx

    projectileBody.position.copy(startPos);
    projectileMesh.position.copy(startPos); // Sync initial mesh position

    // Set velocity in the direction the player is facing
    projectileBody.velocity = new CANNON.Vec3(direction.x, 0, direction.z).scale(PROJECTILE_SPEED);

    // Add to scene and world
    scene.add(projectileMesh);
    world.addBody(projectileBody);

    // Add to sync list and active projectiles list
    const projectileData = { mesh: projectileMesh, body: projectileBody, lifetime: 3.0 }; // 3 second lifetime
    meshesToSync.push(projectileData);
    projectiles.push(projectileData);
    physicsBodies.push(projectileBody);

    // Link body and mesh
    projectileBody.userData = { type: 'projectile', mesh: projectileMesh, data: projectileData };
    projectileMesh.userData = { type: 'projectile', body: projectileBody, data: projectileData };
}

// --- Collision Handling ---
function handlePlayerCollision(event) {
    const otherBody = event.body; // The body the player collided with
    if (!otherBody.userData) return;

    // Player <-> Item Collision
    if (otherBody.userData.type === 'item') {
        const itemName = otherBody.userData.name;
        const itemIndex = gameState.items.findIndex(item => item.id === otherBody.id);

        if (itemIndex > -1 && !gameState.inventory.includes(itemName)) {
            gameState.inventory.push(itemName);
            addLog(`Picked up ${itemName}!`, "pickup");
            updateInventoryDisplay(); // Update UI immediately

            // Remove item from world
            scene.remove(otherBody.userData.mesh);
            world.removeBody(otherBody);
            meshesToSync = meshesToSync.filter(sync => sync.body.id !== otherBody.id);
            physicsBodies = physicsBodies.filter(body => body.id !== otherBody.id);
            gameState.items.splice(itemIndex, 1);
        }
    }

    // Player <-> Monster Collision (Simple damage placeholder)
    else if (otherBody.userData.type === 'monster') {
        // Example: Player takes damage on touch
        // Implement cooldown later
        gameState.stats.hp -= 1; // Monster touch damage
        addLog(`Touched by ${otherBody.userData.monsterType}! HP: ${gameState.stats.hp}`, "combat");
        updateStatsDisplay();
         if (gameState.stats.hp <= 0) {
             gameOver("Defeated by a monster!");
         }
    }
}

function handleProjectileCollision(event) {
    const projectileBody = event.target; // The projectile body itself
    const otherBody = event.body;