const path = require('path');

const { Collection, Util } = require('../../util/');

const { Component, Module } = require('../../structure/interfaces');

class Registry {

    constructor(client) {

        this.client = client;
        this.components = new Collection();

    }

    async loadComponents(dir, classToHandle) {

        const directory = path.join(process.cwd(), 'structure/client/', dir); //Finds directory of component folder relative to current working directory.
        const files = Util.readdirRecursive(directory); //Loops through all folders in the directory and returns the files.

        const loaded = [];

        for(const path of files) {
            const func = require(path);
            if(typeof func !== 'function') { 
                this.client.logger.warn("Attempted to index an invalid function as a component.");
                delete require.cache[path];
                continue;
            }

            const component = new func(this.client); //Instantiates the component class.
            if(classToHandle && !(component instanceof classToHandle)) {
                this.client.logger.warn("Attempted to load an invalid class.");
                delete require.cache[path];
                continue;
            }

            loaded.push(await this.loadComponent(component, path));

        }

        return loaded;

    }

    async loadComponent(component, directory) {
        
        if(!(component instanceof Component)) {
            delete require.cache[directory];
            this.client.logger.warn("Attempted to load an invalid component.");
            return null;
        }

        if(this.components.has(component.resolveable)) {
            this.client.logger.warn("Attempted to reload an existing component.");
            return null;
        }

        if(directory) component.directory = directory;
        if(component.module && typeof component.module === 'string') { //Sets modules or "groups" for each component, specified by their properties.
            let module = this.components.get(`module:${component.module}`);
            if(!module) module = await this.loadComponent(new Module(this.client, { name: component.module }));
            this.components.set(module.resolveable, module);

            component.module = module;
            module.components.set(component.resolveable, component);
        }

        this.components.set(component.resolveable, component);
        this.client.emit('componentUpdate', { component, type: 'LOAD' });
        return component;
    }

    async unloadComponent(component) {
        if(component.module) {
            component.module.components.delete(component.resolveable);
        }
        this.components.delete(component.resolveable);
    }

}

module.exports = Registry;