const fs = require('fs');
const path = require('path');

const TILED_DIR = 'assets/tiled';
const TARGET_MAPS = ['faza1_kmetija.json', 'demo_test.json'];
const ASSET_DIRS = ['../buildings', '../terrain', '../props']; // Relative to TILED_DIR

// 1. Gather Images
const tiles = []; // ARRAY for Tiled JSON compatibility
let nextId = 0; // Start ID at 0
let grassId = null;

ASSET_DIRS.forEach(dir => {
    const fullDir = path.join(__dirname, '..', 'assets', dir.replace('../', ''));
    if (fs.existsSync(fullDir)) {
        const files = fs.readdirSync(fullDir);
        files.forEach(file => {
            if (file.endsWith('.png')) {
                const relPath = path.join(dir, file);

                // Add to array
                tiles.push({
                    id: nextId,
                    image: relPath,
                    imageheight: 64, // Placeholder, Tiled will try to read actual
                    imagewidth: 64
                });

                // Identify Grass
                if (file.includes('grass') || file.includes('resource_pile_food')) { // Fallback
                    if (grassId === null) grassId = nextId;
                }

                nextId++;
            }
        });
    }
});

console.log(`🔍 Found ${tiles.length} assets.`);
console.log(`🌿 Grass ID: ${grassId}`);

// 2. Setup Tileset Object
const autoTileset = {
    "columns": 0,
    "grid": { "height": 1, "orientation": "orthogonal", "width": 1 },
    "margin": 0,
    "name": "Auto_Assets",
    "spacing": 0,
    "tilecount": tiles.length,
    "tileheight": 256,
    "tiles": tiles, // Array!
    "tilewidth": 256,
    "type": "tileset_image_collection"
};

// 3. Process Maps
TARGET_MAPS.forEach(mapFile => {
    const mapPath = path.join(TILED_DIR, mapFile);
    if (!fs.existsSync(mapPath)) {
        console.warn(`⚠️ Map not found: ${mapPath}`);
        return;
    }

    try {
        const mapData = JSON.parse(fs.readFileSync(mapPath, 'utf8'));

        // A. Inject Tileset
        mapData.tilesets = [autoTileset];

        // B. Auto-Ground (Fill Layer 1 with Grass)
        const mapWidth = 100;
        const mapHeight = 100;
        mapData.width = mapWidth;
        mapData.height = mapHeight;

        // Find Ground Layer
        const groundLayer = mapData.layers.find(l => l.name === 'Ground');
        if (groundLayer && grassId !== null) {
            groundLayer.width = mapWidth;
            groundLayer.height = mapHeight;
            groundLayer.data = new Array(mapWidth * mapHeight).fill(grassId + 1); // +1 because GID is local ID + firstgid (1)
            // Wait, for image collections, keys match the ID.
            // But map data uses GID (Global Tile ID).
            // If firstgid is 1 (default for first tileset), then tile with ID 0 is GID 1.
            // So tile with ID X is GID X + 1.
            console.log(`✅ Filled Ground in ${mapFile} with GID ${grassId + 1}`);
        }

        // C. Demo Setup (Landmarks)
        if (mapFile === 'demo_test.json') {
            const objectLayer = mapData.layers.find(l => l.name === 'Objects');
            if (objectLayer) {
                objectLayer.width = mapWidth;
                objectLayer.height = mapHeight;
                // Add 5 random buildings
                const randomIds = tiles.slice(0, 5).map(t => t.id);
                const objData = new Array(mapWidth * mapHeight).fill(0);

                randomIds.forEach((tileId, index) => {
                    const x = 10 + (index * 10);
                    const y = 15;
                    const idx = y * mapWidth + x;
                    if (idx < objData.length) objData[idx] = tileId + 1; // +1 GID
                });
                objectLayer.data = objData;
                console.log(`✅ Placed 5 landmarks in ${mapFile}`);
            }
        }

        // Save
        fs.writeFileSync(mapPath, JSON.stringify(mapData, null, 4));
        console.log(`💾 Saved updated ${mapFile}`);

    } catch (e) {
        console.error(`❌ Error processing ${mapFile}:`, e);
    }
});