const fs = require('fs')
const path = require('path')
const Method = require('./method')
const logger = require('./logger')()

// Reads all scripts in the `scripts` folder, sends to `Method` class to get all methods in the class, and send output to `app.js`
class Controller {
    constructor() {
        this.main = new Promise((res, rej) => {
            if (fs.existsSync('./scripts/')) {
                fs.readdir('./scripts/', (err, files) => {
                    if (err) {
                        logger.Error(`${err.code}: Failed to read directory`)
                        rej(`${err.code}: Failed to read directory`)
                    }

                    this.require = new Map()
                    files.forEach(file => {
                        try {
                            this.require.set(file.replace('.js', ''), require(`../scripts/${file}`)())
                        } catch (err) {
                            logger.Error(`${err.code}: Failed to read ${file}`)
                            rej(`${err.code}: Failed to read ${file}`)
                        }
                    })
                    res(this.require)
                })
            } else {
                fs.mkdirSync('./scripts/')
                fs.writeFile(path.join('./scripts/', 'index.js'), fs.readFileSync('./examples/index.js', 'utf-8'), (err) => {
                    if (err) {
                        logger.Error(`${err.code}: Error writing to file`)
                        rej(`${err.code}: Error writing to file`)
                    }
                })
            }
        }).then(output => {
            return new Promise((res, rej) => {
                const map = output
                const object = {
                    map: output,
                    index: map.get('index'),
                    return: new Map()
                }

                if (object.index) {
                    object.map.forEach((value, key) => {
                        object.return.set(key, this.#GetMethods(value))
                    })
                } else {
                    logger.Error(`ERROR: 'index.js' does not exist`)
                    rej(`ERROR: 'index.js' does not exist`)
                }
                res(object.return)
            })
        })
    }

    async Main(x) {
        return new Promise((res, rej) => {
            this.#LoadModules(x).then(output => {
                if (output) {
                    res(output)
                } else {
                    logger.Error('ERROR: Unable to load modules')
                    rej('ERROR: Unable to load modules')
                }
            })
        })
    }

    #GetMethods(x) {return Method().GetMethods(x)}
    async #LoadModules(x) {
        return new Promise((res, rej) => {
            this.main.then(output => {
                if (output.get('index')) {
                    this.methods = new Map()

                    output.forEach((value, key) => {
                        this.key = key

                        if (this.key === 'index') {
                            this.methods.set('/', value.get('Main')())
                        } else {
                            value.forEach((value, key) => {
                                if (key === 'Main') {
                                    this.methods.set('/' + this.key.toLowerCase(), value(x))
                                } else {
                                    this.methods.set('/' + this.key.toLowerCase() + '/' + key.toLowerCase(), value(x))
                                }
                            })
                        }
                    })
                    if (this.methods !== undefined) {
                        res(this.methods)
                    } else {
                        logger.Error(`Error: Failed to get methods`)
                        rej(`Error: Failed to get methods`)
                    }
                } else {
                    logger.Error(`Error: 'index.js does not exist'`)
                    rej(`Error: 'index.js' does not exist`)
                }
            })
        })
    }
}

module.exports = Controller