require("dotenv").config();
const express = require('express');
const expressSession = require('express-session');
const FileStore = require('session-file-store')(expressSession);
const ejs = require("ejs")
const sqlite3 = require('sqlite3').verbose();
const bcrypt = require("bcrypt")
const crypto = require("crypto")
const app = express();
const port = process.env.SERVER_PORT || 3000;

const db = new sqlite3.Database('astrocom.db', (err) => {
	if (err) {
		console.error('Error connecting to database:', err);
	} else {
		console.log('Connected to SQLite database');
	}
});
// Run migrations
require("./migrations")(db)

// Check if user 1 exists, if not, create it
const saltRounds = 10;

db.get("SELECT * FROM users WHERE id = 1", [], (err, row) => {
	if (err) {
		console.error('Error checking for admin user:', err);
		return;
	}
	if (!row || process.env.RESET_ADMIN == "true") {
		// Destroy all sessions
		sessionStore.clear((err) => {
			if (err) {
				console.error('Error clearing sessions:', err);
				return;
			}
		});
		// delete all users (The big scary one lol)
		db.run("DELETE FROM users", [], (err) => {
			if (err) {
				console.error('Error deleting users:', err);
				return;
			}
		});
		// Generate 32 char random string
		const passwd = crypto.randomBytes(32).toString('hex');
		bcrypt.hash(passwd, saltRounds, (err, hash) => {
			if (err) {
				console.error('Error creating hash:', err);
				return;
			}
			db.run("INSERT INTO users (id, username, passwordHash) VALUES (1, 'admin', ?)",
				[hash],
				(err) => {
					if (err) {
						console.error('Error creating admin user:', err);
					} else {
						console.log(`Created admin user with password: ${passwd}`);
					}
				});
		});
	}
});

app.use(express.json());
app.use(express.urlencoded({ extended: true }));

const fileStoreOptions = {};
const sessionStore = new FileStore(fileStoreOptions);

app.use(expressSession({
	store: sessionStore,
	secret: process.env.SESSION_SECRET || 'default_secret',
	resave: false,
	saveUninitialized: false,
	cookie: {
		secure: process.env.NODE_ENV === 'production',
		maxAge: 24 * 60 * 60 * 1000 // 24 hours
	}
}));

app.set('view engine', 'ejs');
app.set('views', __dirname + '/views');
// Static files
app.use(express.static('public'));

// Admin routes

// admin/logout
app.get('/admin/logout', (req, res) => {
	req.session.destroy();
	res.redirect('/admin/login');
});

app.get('/admin/login', (req, res) => {
	res.render('admin/login');
});

app.get('/admin', (req, res) => {
	if (!req.session.adminAuthenticated) {
		res.redirect('/admin/login');
		return;
	}
	res.render('admin/index', { user: req.session.user });
});

app.get('/admin/create', (req, res) => {
	if (!req.session.adminAuthenticated) {
		res.redirect('/admin/login');
		return;
	}
	res.render('admin/create', { user: req.session.user });
});

app.get('/admin/route/:id', (req, res) => {
	if (!req.session.adminAuthenticated) {
		res.redirect('/admin/login');
		return;
	}
	db.get('SELECT * FROM routes WHERE id = ?', [req.params.id], (err, row) => {
		if (err) {
			console.error('Error getting route:', err);
			res.status(500).send('Internal server error');
			return;
		}
		if (!row) {
			res.status(404).send('Not Found');
			return;
		}
		res.render('admin/edit', { user: req.session.user, data: row });
	});
});

app.post('/admin/login', (req, res) => {
	const username = req.body.username;
	const password = req.body.password;
	db.get("SELECT * FROM users WHERE username = ?", [String(username)], (err, row) => {
		if (err) {
			console.error('Error getting user:', err);
			res.status(500).send('Internal server error');
			return;
		}
		if (!row) {
			res.status(401).send('Unauthorized (Not Found)');
			return;
		}
		bcrypt.compare(password, row.passwordHash, (err, result) => {
			if (err) {
				console.error('Error comparing password:', err);
				res.status(500).send('Internal server error');
				return;
			}
			if (result) {
				req.session.adminAuthenticated = true;
				req.session.user = row.username;
				res.redirect('/admin');
			} else {
				res.status(401).send('Unauthorized');
			}
		});
	});
})

app.get('/api/v1/admin/routes', (req, res) => { // Get all routes
	if (!req.session.adminAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	db.all('SELECT * FROM routes', (err, rows) => {
		if (err) {
			console.error('Error getting routes:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		res.json(rows);
	});
});

app.get('/api/v1/admin/route/:id', (req, res) => { // Get route
	if (!req.session.adminAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	db.get('SELECT * FROM routes WHERE id = ?', [req.params.id], (err, row) => {
		if (err) {
			console.error('Error getting route:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		if (!row) {
			res.status(404).json({ error: 'Not Found' });
			return;
		}
		res.json(row);
	});
});

app.post('/api/v1/admin/route', (req, res) => { // Create a new route
	if (!req.session.adminAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	const server = req.body.server;
	const port = req.body.port;
	const auth = req.body.auth || "from-astrocom";
	const secret = req.body.secret || crypto.randomBytes(15).toString('hex');
	const block_start = req.body.block_start;
	const block_length = req.body.block_length || 9999;
	const apiKey = crypto.randomBytes(32).toString('hex');
	// Validate all inputs exist
	if (!server || !port || !block_start) {
		res.status(400).json({ error: 'Bad Request' });
		return;
	}
	// Check if route already exists (OR conditions on server, and block range)
	db.get('SELECT * FROM routes WHERE server = ? OR block_start <= ? AND block_start + block_length >= ?', [server, block_start, block_start], (err, row) => {
		if (err) {
			console.error('Error checking for existing route:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		if (row) {
			res.status(409).json({ error: 'Conflict' });
			return;
		} else {
			db.run('INSERT INTO routes (server, port, auth, secret, block_start, block_length, apiKey) VALUES (?, ?, ?, ?, ?, ?, ?)',
				[server, port, auth, secret, block_start, block_length, apiKey],
				(err) => {
					if (err) {
						console.error('Error creating route:', err);
						res.status(500).json({ error: 'Internal server error' });
						return;
					}
					res.status(201).json({ message: 'Created' });
				});
		}
	});
});

app.put('/api/v1/admin/route/:id', (req, res) => { // Update a route
	// Check if authenticated
	if (!req.session.adminAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	// Check if route exists
	db.get('SELECT * FROM routes WHERE id = ?', [req.params.id], (err, row) => {
		if (err) {
			console.error('Error getting route:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		if (!row) {
			res.status(404).json({ error: 'Not Found' });
			return;
		}
		// Update route
		const server = req.body.server || row.server;
		const port = req.body.port || row.port;
		const auth = req.body.auth || row.auth;
		const secret = req.body.secret || row.secret;
		const block_start = req.body.block_start || row.block_start;
		const block_length = req.body.block_length || row.block_length;
		db.run('UPDATE routes SET server = ?, port = ?, auth = ?, secret = ?, block_start = ?, block_length = ? WHERE id = ?',
			[server, port, auth, secret, block_start, block_length, req.params.id],
			(err) => {
				if (err) {
					console.error('Error updating route:', err);
					res.status(500).json({ error: 'Internal server error' });
					return;
				}
				res.json({ message: 'Updated' });
			});
	});
});

app.delete('/api/v1/admin/route/:id', (req, res) => { // Delete a route
	if (!req.session.adminAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	db.run('DELETE FROM routes WHERE id = ?', [req.params.id], (err) => {
		if (err) {
			console.error('Error deleting route:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		res.json({ message: 'Deleted' });
	});
});

app.delete('/api/v1/admin/directory/:number', (req, res) => { // Delete a directory entry
	if (!req.session.adminAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	const number = Number(req.params.number);
	if (!number) {
		res.status(400).json({ error: 'Bad Request' });
		return;
	}
	db.run('DELETE FROM directory WHERE number = ?', [number], (err) => {
		if (err) {
			console.error('Error deleting directory entry:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		res.status(200).json({ message: 'Deleted' });
	});
});

// == END ADMIN ROUTES ==

// == User routes == // allows someone to log in with their API key and add entries to the Directory (as long as the number is within their block range)
app.get('/user', (req, res) => {
	if (!req.session.userAuthenticated) {
		res.redirect('/user/login');
		return;
	}
	res.render('user/index', { user: req.session.user });
});

app.get('/user/login', (req, res) => {
	res.render('user/login');
});

app.post('/user/login', (req, res) => {
	const apiKey = req.body.apiKey;
	db.get("SELECT * FROM routes WHERE apiKey = ?", [apiKey], (err, row) => {
		if (err) {
			console.error('Error getting route:', err);
			res.status(500).send('Internal server error');
			return;
		}
		if (!row) {
			res.status(401).send('Unauthorized');
			return;
		}
		req.session.userAuthenticated = true;
		req.session.userData = row;
		res.redirect('/user');
	});
});

app.get('/user/logout', (req, res) => {
	req.session.destroy();
	res.redirect('/user/login');
});

app.get('/api/v1/user/route', (req, res) => { // Get route
	if (!req.session.userAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	res.json(req.session.userData);
});

app.put('/api/v1/user/route', (req, res) => { // Update route
	if (!req.session.userAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	if (!req.session.userData.apiKey) {
		req.session.destroy(); // Something weird happened, destroy session
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	// Does not allow for ID to be specified, always update current users route
	const server = req.body.server || req.session.userData.server;
	const port = req.body.port || req.session.userData.port;
	const auth = req.body.auth || req.session.userData.auth;
	const secret = req.body.secret || req.session.userData.secret;
	// We don't allow block changes, admins only.
	const block_start = req.session.userData.block_start;
	const block_length = req.session.userData.block_length;
	const apiKey = req.session.userData.apiKey;
	db.run('UPDATE routes SET server = ?, port = ?, auth = ?, secret = ?, block_start = ?, block_length = ? WHERE apiKey = ?',
		[server, port, auth, secret, block_start, block_length, apiKey],
		(err) => {
			if (err) {
				console.error('Error updating route:', err);
				res.status(500).json({ error: 'Internal server error' });
				return;
			}
			res.json({ message: 'Updated' });
		});
});

app.get('/api/v1/user/directory', (req, res) => { // Get directory entries created by user
	if (!req.session.userAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	db.all('SELECT * FROM directory WHERE route = ?', [req.session.userData.id], (err, rows) => {
		if (err) {
			console.error('Error getting routes:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		res.json(rows);
	});
});

app.post('/api/v1/user/directory', (req, res) => { // Create a new directory entry
	// Check if authenticated
	if (!req.session.userAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	// Check that the number is within the block range for the current user
	var number = Number(req.body.number);
	var name = String(req.body.name);
	if (!number || !name) {
		res.status(400).json({ error: 'Bad Request' });
		return;
	}

	if (number < req.session.userData.block_start || number > req.session.userData.block_start + req.session.userData.block_length) {
		res.status(403).json({ error: 'Forbidden' });
		return;
	}

	// Remove html
	name = require("escape-html")(name);
	const route = req.session.userData.id;
	// If number already exists, update, otherwise insert
	db.get('SELECT * FROM directory WHERE number = ? AND route = ?', [number, route], (err, row) => {
		if (err) {
			console.error('Error checking for existing directory entry:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		if (row) {
			db.run('UPDATE directory SET name = ? WHERE number = ? AND route = ?',
				[name, number, route],
				(err) => {
					if (err) {
						console.error('Error updating directory entry:', err);
						res.status(500).json({ error: 'Internal server error' });
						return;
					}
					res.json({ message: 'Updated' });
				});
		} else {
			db.run('INSERT INTO directory (number, name, route) VALUES (?, ?, ?)',
				[number, name, route],
				(err) => {
					if (err) {
						console.error('Error creating directory entry:', err);
						res.status(500).json({ error: 'Internal server error' });
						return;
					}
					res.status(201).json({ message: 'Created' });
				});
		}
	});
});

app.delete('/api/v1/user/directory/:number', (req, res) => { // Delete a directory entry
	if (!req.session.userAuthenticated) {
		res.status(401).json({ error: 'Unauthorized' });
		return;
	}
	const number = Number(req.params.number);
	if (!number) {
		res.status(400).json({ error: 'Bad Request' });
		return;
	}
	db.run('DELETE FROM directory WHERE number = ? AND route = ?', [number, req.session.userData.id], (err) => {
		if (err) {
			console.error('Error deleting directory entry:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		res.status(200).json({ message: 'Deleted' });
	});
});

// == END USER ROUTES ==

// == Directory routes == (unauthenticated)

app.get("/api/v1/directory", (req, res) => {
	db.all("SELECT * FROM directory", (err, rows) => {
		if (err) {
			console.error('Error getting directory:', err);
			res.status(500).json({ error: 'Internal server error' });
			return;
		}
		res.json(rows);
	});
});

// Other public endpoints that need special handling
discordInviteCache = {time: 0, url: ""};

app.get("/discord", (req, res) => {
	// fetch from process.env.WIDGET_URL, get json body, redirect to body.instant_invite. Cache url for 5 minutes
	if (Date.now() - discordInviteCache.time < 300000) {
		res.redirect(discordInviteCache.url);
		return;
	}
	fetch(process.env.WIDGET_URL)
		.then(response => response.json())
		.then(data => {
			discordInviteCache.time = Date.now();
			discordInviteCache.url = data.instant_invite;
			res.redirect(data.instant_invite);
		})
		.catch(error => {
			console.error('Error fetching discord invite:', error);
			res.status(500).send('Internal server error');
		});
});

// Query to get a route
app.get('/api/v1/route/:apiKey/:ani/:number', (req, res) => {
	const apiKey = req.params.apiKey;
	const number = Number(req.params.number);
	const ani = Number(req.params.ani);
	db.get("SELECT * FROM routes WHERE apiKey = ? AND block_start <= ? AND block_start + block_length >= ?", [apiKey, ani, ani], (err, row) => {
		// If no row or error, return 401
		if (err || !row) {
			console.error(err);
			res.status(401).send(`${process.env.MSG_ROUTE_ADDRESS}/401`)
			return;
		}
		db.get('SELECT * FROM routes WHERE block_start <= ? AND block_start + block_length >= ?', [number, number], (err, row) => {
			if (err) {
				console.error('Error getting route:', err);
				res.status(500).send(`${process.env.MSG_ROUTE_ADDRESS}/500`)
			} else if (row) {
				// Check if the ANI is within the block range
				// If it is, return `local`
				console.log(`New Call: ${ani} -> ${number}`);
				if (ani >= row.block_start && ani <= row.block_start + row.block_length) {
					res.status(200).send('local');
				} else {
					res.status(200).send(`IAX2/${row.auth}:${row.secret}@${row.server}:${row.port}/${number}`);
				}
			} else {
				res.status(404).send(`${process.env.MSG_ROUTE_ADDRESS}/404`);
			}
		});
	});
});

app.get('/api/v1', (req, res) => { // Backwards compatibility with TandmX cause why not, it's easy
	const apiKey = req.query.auth;
	const number = Number(req.query.number);
	const ani = Number(req.query.ani);
	db.get("SELECT * FROM routes WHERE apiKey = ? AND block_start <= ? AND block_start + block_length >= ?", [apiKey, ani, ani], (err, row) => {
		// If no row or error, return 401
		if (err || !row) {
			console.error(err);
			res.status(401).send(`${process.env.MSG_ROUTE_ADDRESS}/401`)
			return;
		}
		db.get('SELECT * FROM routes WHERE block_start <= ? AND block_start + block_length >= ?', [number, number], (err, row) => {
			if (err) {
				console.error('Error getting route:', err);
				res.status(500).send(`${process.env.MSG_ROUTE_ADDRESS}/500`)
			} else if (row) {
				// Check if the ANI is within the block range
				// If it is, return `local`
				console.log(`New Call: ${ani} -> ${number}`);
				if (ani >= row.block_start && ani <= row.block_start + row.block_length) {
					res.status(200).send('local');
				} else {
					res.status(200).send(`IAX2/${row.auth}:${row.secret}@${row.server}:${row.port}/${number}`);
				}
			} else {
				res.status(404).send(`${process.env.MSG_ROUTE_ADDRESS}/404`);
			}
		});
	});
});

// Start server
app.listen(port, () => {
	console.log(`Listening on port ${port}`);
});