const { app, BrowserWindow, ipcMain } = require('electron/main');
const path = require('node:path');
const fs = require('fs');
const log = require('electron-log/main');


class Config {
    url = "";
    whitelist = [];
    logPath = "tooloop-kiosk-browser.log";
}


// -----------------------------------------------------------------------------
// Private fields
// -----------------------------------------------------------------------------
const locations = [
    '/assets/presentation',
    path.join(app.getPath('appData'), app.name),
    app.getAppPath()
];
let configPath;
let configWindow;
let saveCallback;

// -----------------------------------------------------------------------------
// Public fields
// -----------------------------------------------------------------------------
exports.data = new Config();


// -----------------------------------------------------------------------------
// Public functions
// -----------------------------------------------------------------------------

/**
 * Loads a config file from disc.
 * The file is expected to be named `config.json` and is searched for in these
 * locations and in this order:
 * 
 * 1. `/assets/presentation/config.json` (Tooloop OS)
 * 2. appData directory
 * 3. Path of the executable (Development)
 */
exports.load = () => {
    // Check all locations
    for (const location of locations) {
        // Update the filepath
        let configFile = path.join(location, 'config.json');
        try {
            // Try access
            fs.accessSync(configFile);

            // Parse the file if found
            console.info('Found config file at ' + configFile);
            const fileContent = fs.readFileSync(configFile, { encoding: 'utf8' });
            this.data = JSON.parse(fileContent);

            // store successful location
            configPath = location;

            // Break the loop
            break;
        } catch (err) {
            // console.info('No config file found at ' + location);
        }
    }
}

/**
 * Saves the current configuration to disc.
 * These locations are tried in this order:
 * 
 * 1. `/assets/presentation/config.json` (Tooloop OS)
 * 2. appData directory
 * 
 * @param {Config} newConfig 
 */
exports.save = (newConfig) => {
    if (!configPath) {
        try {
            // /assets/presentation
            fs.accessSync(locations[0]);
            configPath = locations[0];
        } catch (error) {
            // appData
            configPath = locations[1];
        }
    }

    // Store changes
    if (this.data.url != newConfig.url) {
        this.data.url = newConfig.url;
    }

    this.data.whitelist = [];
    let whitelist = newConfig.whitelist.split(";");
    whitelist = whitelist.filter(function (entry) { return entry.trim() != ''; });
    whitelist.forEach(
        token => {
            this.data.whitelist.push(token.replace(/\r?\n|\r/g, ""));
        }
    );

    this.data.logPath = newConfig.logPath;

    // Write file
    let configFile = path.join(configPath, 'config.json');
    fs.writeFile(
        configFile,
        JSON.stringify(this.data, null, "  "),
        (error) => {
            if (error) log.warn('Error writing to ' + configPath, error);
            log.info("Saved config to " + configFile);
        }
    );

    // Update UI with new values
    configWindow.webContents.send('update-config', this.data);

    // Notify listeners
    saveCallback(this.data);

}


/**
 * Creates a modal config view and attaches as to the main window
 * 
 * @param {BrowserWindow} parent Reference to the parent window
 * @param {function(Config)} saveCallback
 */
exports.showWindow = (parent, callback) => {

    // create lazily
    if (configWindow == undefined) {
        console.log("create windows");
        saveCallback = callback;

        configWindow = new BrowserWindow({
            parent: parent,
            width: 640,
            height: 460,
            minimizable: false,
            maximizable: false,
            fullscreenable: false,
            backgroundColor: '#1f1f1f',
            autoHideMenuBar: true,
            excludedFromShownWindowsMenu: true,
            webPreferences: {
                preload: path.join(__dirname, 'configPreload.js')
            }
        });

        configWindow.on('close', (event) => {
            event.preventDefault();
            configWindow.hide();
        });

        ipcMain.on('save-config', (event, configData) => {
            configWindow.hide();
            this.save(configData);
        });
        ipcMain.on('cancel-config', (event) => {
            configWindow.hide();
            configWindow.webContents.send('update-config', this.data);
        });

        configWindow.loadFile('./html/config.html');
    }

    // update text field values
    configWindow.webContents.send('update-config', this.data);

    // show window
    configWindow.show();
}