const {app, BrowserWindow, shell, ipcMain} = require('electron');
const path = require('path');
const fs = require('fs');

let mainWindow = null;

const isDev = process.env.NODE_ENV === 'development' || !app.isPackaged;

const gotTheLock = app.requestSingleInstanceLock();
if (!gotTheLock) {
    console.log('Another instance is already running, quitting...');
    app.quit();
    process.exit(0);
} else {
    app.on('second-instance', (event, commandLine, workingDirectory) => {
        console.log('Second instance detected, focusing existing window...');
        if (mainWindow) {
            if (mainWindow.isMinimized()) mainWindow.restore();
            mainWindow.focus();
            mainWindow.show();
        }
    });
}

function createWindow() {
    mainWindow = new BrowserWindow({
        width: 1200,
        height: 800,
        minWidth: 800,
        minHeight: 600,
        title: 'Termix',
        icon: isDev
            ? path.join(__dirname, '..', 'public', 'icon.png')
            : path.join(process.resourcesPath, 'public', 'icon.png'),
        webPreferences: {
            nodeIntegration: false,
            contextIsolation: true,
            webSecurity: !isDev,
            preload: path.join(__dirname, 'preload.js')
        },
        show: false
    });

    if (process.platform !== 'darwin') {
        mainWindow.setMenuBarVisibility(false);
    }

    if (isDev) {
        mainWindow.loadURL('http://localhost:5173');
        mainWindow.webContents.openDevTools();
    } else {
        const indexPath = path.join(__dirname, '..', 'dist', 'index.html');
        console.log('Loading frontend from:', indexPath);
        mainWindow.loadFile(indexPath);
    }

    mainWindow.once('ready-to-show', () => {
        console.log('Window ready to show');
        mainWindow.show();
    });

    mainWindow.webContents.on('did-fail-load', (event, errorCode, errorDescription, validatedURL) => {
        console.error('Failed to load:', errorCode, errorDescription, validatedURL);
    });

    mainWindow.webContents.on('did-finish-load', () => {
        console.log('Frontend loaded successfully');
    });

    mainWindow.on('close', (event) => {
        if (process.platform === 'darwin') {
            event.preventDefault();
            mainWindow.hide();
        }
    });

    mainWindow.on('closed', () => {
        mainWindow = null;
    });

    mainWindow.webContents.setWindowOpenHandler(({url}) => {
        shell.openExternal(url);
        return {action: 'deny'};
    });
}

ipcMain.handle('get-app-version', () => {
    return app.getVersion();
});

ipcMain.handle('get-platform', () => {
    return process.platform;
});

ipcMain.handle('get-server-config', () => {
    try {
        const userDataPath = app.getPath('userData');
        const configPath = path.join(userDataPath, 'server-config.json');

        if (fs.existsSync(configPath)) {
            const configData = fs.readFileSync(configPath, 'utf8');
            return JSON.parse(configData);
        }
        return null;
    } catch (error) {
        console.error('Error reading server config:', error);
        return null;
    }
});

ipcMain.handle('save-server-config', (event, config) => {
    try {
        const userDataPath = app.getPath('userData');
        const configPath = path.join(userDataPath, 'server-config.json');

        if (!fs.existsSync(userDataPath)) {
            fs.mkdirSync(userDataPath, {recursive: true});
        }

        fs.writeFileSync(configPath, JSON.stringify(config, null, 2));
        return {success: true};
    } catch (error) {
        console.error('Error saving server config:', error);
        return {success: false, error: error.message};
    }
});


ipcMain.handle('test-server-connection', async (event, serverUrl) => {
    try {
        let fetch;
        try {
            fetch = globalThis.fetch || require('node:fetch');
        } catch (e) {
            const https = require('https');
            const http = require('http');
            const {URL} = require('url');

            fetch = (url, options = {}) => {
                return new Promise((resolve, reject) => {
                    const urlObj = new URL(url);
                    const isHttps = urlObj.protocol === 'https:';
                    const client = isHttps ? https : http;

                    const req = client.request(url, {
                        method: options.method || 'GET',
                        headers: options.headers || {},
                        timeout: options.timeout || 5000
                    }, (res) => {
                        let data = '';
                        res.on('data', chunk => data += chunk);
                        res.on('end', () => {
                            resolve({
                                ok: res.statusCode >= 200 && res.statusCode < 300,
                                status: res.statusCode,
                                text: () => Promise.resolve(data),
                                json: () => Promise.resolve(JSON.parse(data))
                            });
                        });
                    });

                    req.on('error', reject);
                    req.on('timeout', () => {
                        req.destroy();
                        reject(new Error('Request timeout'));
                    });

                    if (options.body) {
                        req.write(options.body);
                    }
                    req.end();
                });
            };
        }

        const normalizedServerUrl = serverUrl.replace(/\/$/, '');

        const healthUrl = `${normalizedServerUrl}/health`;

        try {
            const response = await fetch(healthUrl, {
                method: 'GET',
                timeout: 5000
            });

            if (response.ok) {
                const data = await response.text();

                if (data.includes('<html') || data.includes('<!DOCTYPE') || data.includes('<head>') || data.includes('<body>')) {
                    console.log('Health endpoint returned HTML instead of JSON - not a Termix server');
                    return {
                        success: false,
                        error: 'Server returned HTML instead of JSON. This does not appear to be a Termix server.'
                    };
                }

                try {
                    const healthData = JSON.parse(data);
                    if (healthData && (
                        healthData.status === 'ok' ||
                        healthData.status === 'healthy' ||
                        healthData.healthy === true ||
                        healthData.database === 'connected'
                    )) {
                        return {success: true, status: response.status, testedUrl: healthUrl};
                    }
                } catch (parseError) {
                    console.log('Health endpoint did not return valid JSON');
                }
            }
        } catch (urlError) {
            console.error('Health check failed:', urlError);
        }

        try {
            const versionUrl = `${normalizedServerUrl}/version`;
            const response = await fetch(versionUrl, {
                method: 'GET',
                timeout: 5000
            });

            if (response.ok) {
                const data = await response.text();

                if (data.includes('<html') || data.includes('<!DOCTYPE') || data.includes('<head>') || data.includes('<body>')) {
                    console.log('Version endpoint returned HTML instead of JSON - not a Termix server');
                    return {
                        success: false,
                        error: 'Server returned HTML instead of JSON. This does not appear to be a Termix server.'
                    };
                }

                try {
                    const versionData = JSON.parse(data);
                    if (versionData && (
                        versionData.status === 'up_to_date' ||
                        versionData.status === 'requires_update' ||
                        (versionData.localVersion && versionData.version && versionData.latest_release)
                    )) {
                        return {
                            success: true,
                            status: response.status,
                            testedUrl: versionUrl,
                            warning: 'Health endpoint not available, but server appears to be running'
                        };
                    }
                } catch (parseError) {
                    console.log('Version endpoint did not return valid JSON');
                }
            }
        } catch (versionError) {
            console.error('Version check failed:', versionError);
        }

        return {
            success: false,
            error: 'Server is not responding or does not appear to be a valid Termix server. Please ensure the server is running and accessible.'
        };
    } catch (error) {
        return {success: false, error: error.message};
    }
});

app.whenReady().then(() => {
    createWindow();
    console.log('Termix started successfully');
});

app.on('window-all-closed', () => {
    if (process.platform !== 'darwin') {
        app.quit();
    }
});

app.on('activate', () => {
    if (BrowserWindow.getAllWindows().length === 0) {
        createWindow();
    } else if (mainWindow) {
        mainWindow.show();
    }
});

app.on('before-quit', () => {
    console.log('App is quitting...');
});

app.on('will-quit', () => {
    console.log('App will quit...');
});

process.on('uncaughtException', (error) => {
    console.error('Uncaught Exception:', error);
});

process.on('unhandledRejection', (reason, promise) => {
    console.error('Unhandled Rejection at:', promise, 'reason:', reason);
});