import express from 'express';
import multer from 'multer';
import cors from 'cors';
import fs from 'fs';
import path from 'path';
import { fileURLToPath } from 'url';
import { createClient } from "@libsql/client";
import dotenv from 'dotenv';

dotenv.config();

const __filename = fileURLToPath(import.meta.url);
const __dirname = path.dirname(__filename);

const app = express();
const PORT = process.env.PORT || 8080;

app.use(cors());
app.use(express.json());

// Directories
const DATA_DIR = path.join(__dirname, 'data');
const UPLOAD_DIR = path.join(__dirname, 'uploads');

// Ensure directories exist
if (!fs.existsSync(DATA_DIR)) fs.mkdirSync(DATA_DIR, { recursive: true });
if (!fs.existsSync(UPLOAD_DIR)) fs.mkdirSync(UPLOAD_DIR, { recursive: true });

// Initialize LibSQL
const db = createClient({
    url: "file:data/data.db"
});

// Initialize Schema
const initDB = async () => {
    try {
        await db.execute(`
            CREATE TABLE IF NOT EXISTS photos (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                url TEXT NOT NULL,
                title TEXT,
                description TEXT,
                date TEXT,
                location TEXT,
                camera TEXT,
                lens TEXT,
                iso TEXT,
                aperture TEXT,
                shutter TEXT,
                focalLength TEXT,
                gps_lat REAL,
                gps_lng REAL,
                file_name TEXT,
                created_at DATETIME DEFAULT CURRENT_TIMESTAMP
            )
        `);
        console.log("Database initialized");
    } catch (err) {
        console.error("Database initialization failed", err);
    }
};

initDB();

// Multer Storage
const storage = multer.diskStorage({
    destination: (req, file, cb) => {
        cb(null, UPLOAD_DIR);
    },
    filename: (req, file, cb) => {
        // Use timestamp to ensure unique filenames
        const ext = path.extname(file.originalname);
        const name = path.basename(file.originalname, ext).replace(/[^a-zA-Z0-9]/g, '-');
        cb(null, `${Date.now()}-${name}${ext}`);
    }
});

const upload = multer({ storage });

// API Routes

// Get all photos
app.get('/api/photos', async (req, res) => {
    try {
        const result = await db.execute("SELECT * FROM photos ORDER BY date DESC");
        // Map result rows to object format if needed, but LibSQL returns objects usually
        // We might need to reconstruct the nested 'settings' or 'gps' objects for the frontend
        const photos = result.rows.map(row => ({
            id: row.id,
            url: row.url,
            title: row.title,
            description: row.description,
            date: row.date,
            location: row.location,
            camera: row.camera,
            lens: row.lens,
            settings: {
                iso: row.iso,
                aperture: row.aperture,
                shutter: row.shutter,
                focalLength: row.focalLength
            },
            gps: (row.gps_lat && row.gps_lng) ? { lat: row.gps_lat, lng: row.gps_lng } : null,
            fileName: row.file_name
        }));
        res.json(photos);
    } catch (err) {
        console.error(err);
        res.status(500).json({ error: "Failed to fetch photos" });
    }
});

// Upload a photo
app.post('/api/photos', upload.single('image'), async (req, res) => {
    try {
        if (!req.file) {
            return res.status(400).json({ error: 'No image uploaded' });
        }

        const metadata = JSON.parse(req.body.metadata || '{}');
        const fileName = req.file.filename;
        const url = `/uploads/${fileName}`;

        // Insert into DB
        await db.execute({
            sql: `INSERT INTO photos (
                url, title, description, date, location, camera, lens, 
                iso, aperture, shutter, focalLength, gps_lat, gps_lng, file_name
            ) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)`,
            args: [
                url,
                metadata.title || '',
                metadata.description || '',
                metadata.date || '',
                metadata.location || '',
                metadata.camera || '',
                metadata.lens || '',
                metadata.settings?.iso || '',
                metadata.settings?.aperture || '',
                metadata.settings?.shutter || '',
                metadata.settings?.focalLength || '',
                metadata.gps?.lat || null,
                metadata.gps?.lng || null,
                fileName
            ]
        });

        // We could fetch the inserted row, but for now just return success
        // Simulating the returned object
        const newPhoto = {
            id: Date.now(), // approximation, real ID is in DB
            url,
            ...metadata
        };

        res.status(201).json(newPhoto);
    } catch (error) {
        console.error("Upload error", error);
        res.status(500).json({ error: 'Upload failed' });
    }
});

// Delete a photo
app.delete('/api/photos/:id', async (req, res) => {
    const id = parseInt(req.params.id);

    try {
        // Get filename first
        const result = await db.execute({
            sql: "SELECT file_name FROM photos WHERE id = ?",
            args: [id]
        });

        if (result.rows.length === 0) {
            return res.status(404).json({ error: 'Photo not found' });
        }

        const fileName = result.rows[0].file_name;

        // Remove from DB
        await db.execute({
            sql: "DELETE FROM photos WHERE id = ?",
            args: [id]
        });

        // Remove file
        if (fileName) {
            const filePath = path.join(UPLOAD_DIR, fileName);
            if (fs.existsSync(filePath)) {
                fs.unlinkSync(filePath);
            }
        }

        res.json({ success: true });
    } catch (err) {
        console.error("Delete error", err);
        res.status(500).json({ error: "Delete failed" });
    }
});

// Serve Uploads
app.use('/uploads', express.static(UPLOAD_DIR));

// Favicon Storage
const faviconStorage = multer.diskStorage({
    destination: (req, file, cb) => {
        cb(null, UPLOAD_DIR);
    },
    filename: (req, file, cb) => {
        cb(null, 'favicon.png');
    }
});
const uploadFavicon = multer({ storage: faviconStorage });

// Upload Favicon
app.post('/api/favicon', uploadFavicon.single('favicon'), (req, res) => {
    if (!req.file) return res.status(400).json({ error: 'No file uploaded' });
    res.json({ success: true, url: '/uploads/favicon.png' });
});

// Serve Favicon (Dynamic)
app.get('/api/favicon', (req, res) => {
    const faviconPath = path.join(UPLOAD_DIR, 'favicon.png');
    if (fs.existsSync(faviconPath)) {
        res.sendFile(faviconPath);
    } else {
        // Fallback to default
        res.status(404).send('Not found');
    }
});

// Serve Frontend (Production)
const DIST_DIR = path.join(__dirname, 'dist');
if (fs.existsSync(DIST_DIR)) {
    app.use(express.static(DIST_DIR));
    // SPA Fallback
    app.get(/.*/, (req, res) => {
        res.sendFile(path.join(DIST_DIR, 'index.html'));
    });
}

app.listen(PORT, () => {
    console.log(`Server running on port ${PORT}`);
});