const express = require('express');
const { KEY_TYPE_ADMIN } = require('../database');
const { EVENT_TYPES } = require('../constants/eventTypes');

const router = express.Router();

const DEFAULT_ADMIN_BLOCKED_COMMANDS = new Set([
    'stop',
    'deop',
    'op',
    'ban',
    'ban-ip',
    'banlist',
    'pardon',
    'pardon-ip',
    'whitelist',
    'kick',
    'restart',
    'reload',
    'save-all',
    'save-on',
    'save-off'
]);

function parseCommandList(value) {
    if (!value) {
        return [];
    }
    return value
        .split(',')
        .map((entry) => entry.trim().toLowerCase())
        .filter(Boolean);
}

const adminAllowedCommands = new Set(parseCommandList(process.env.ADMIN_ALLOWED_COMMANDS));
const adminBlockedCommandsFromEnv = parseCommandList(process.env.ADMIN_BLOCKED_COMMANDS);
const adminBlockedCommands = adminBlockedCommandsFromEnv.length
    ? new Set(adminBlockedCommandsFromEnv)
    : DEFAULT_ADMIN_BLOCKED_COMMANDS;

function normalizeCommand(command) {
    const trimmed = command.trim();
    if (!trimmed) {
        return null;
    }
    const token = trimmed.split(/\s+/)[0].toLowerCase();
    const base = token.includes(':') ? token.split(':').pop() : token;
    return { token, base };
}

function isAdminCommandAllowed(command) {
    const normalized = normalizeCommand(command);
    if (!normalized) {
        return false;
    }
    const { token, base } = normalized;
    if (adminAllowedCommands.size) {
        return adminAllowedCommands.has(token) || adminAllowedCommands.has(base);
    }
    return !(adminBlockedCommands.has(token) || adminBlockedCommands.has(base));
}

function createServerRouter(db, manager, requireCommandKey) {
    router.get('/info', requireCommandKey, (req, res) => {
        try {
            const requestedServerId = req.apiKey.keyType === KEY_TYPE_ADMIN
                ? (req.query.server_id || req.apiKey.serverId)
                : req.apiKey.serverId;

            if (!requestedServerId) {
                return res.status(400).json({ detail: 'server_id is required for this key' });
            }

            const serverInfo = {
                server_id: requestedServerId,
                status: 'running',
                online_players: 5,
                max_players: 20,
                version: '1.20.1',
                uptime: '2h 30m',
                tps: 19.8
            };

            res.json(serverInfo);
        } catch (error) {
            res.status(500).json({ detail: error.message });
        }
    });

    router.post('/command', requireCommandKey, (req, res) => {
        try {
            const { command, server_id: requestedServerId } = req.body;

            if (!command || typeof command !== 'string') {
                return res.status(400).json({ detail: 'Command is required' });
            }

            const isAdmin = req.apiKey.keyType === KEY_TYPE_ADMIN;
            if (isAdmin && !isAdminCommandAllowed(command)) {
                return res.status(403).json({ detail: 'Command is not allowed for Admin Key' });
            }

            const targetServerId = isAdmin ? (requestedServerId || req.apiKey.serverId) : req.apiKey.serverId;
            if (!targetServerId) {
                return res.status(400).json({ detail: 'server_id is required for this key' });
            }

            console.log(`[Server Command] ${targetServerId}: ${command}`);

            const commandEvent = {
                event_type: EVENT_TYPES.SERVER_COMMAND,
                server_name: targetServerId,
                timestamp: new Date().toISOString(),
                data: {
                    command: command,
                    executed_by: req.apiKey.id,
                    server_id: targetServerId
                }
            };

            manager.broadcastToAll({
                type: 'minecraft_event',
                event: commandEvent,
                source_key_id_prefix: req.apiKey.id.substring(0, 8)
            });

            res.json({
                message: 'Command sent successfully',
                command: command,
                server_id: targetServerId
            });
        } catch (error) {
            res.status(500).json({ detail: error.message });
        }
    });

    return router;
}

module.exports = createServerRouter;