const escapeRegex = require('escape-string-regexp');
const { Structures } = require('discord.js');

const Guild = Structures.extend('Guild', (Guild) => {

    class ExtendedGuild extends Guild {

        constructor(...args) {

            super(...args);

            this._settings = null; //internal cache of current guild's settings; should ALWAYS stay the same as database.
            this._permissions = null; //internal cache, should always match database.
            this.callbacks = [];

        }

        //Fetch and cache settings
        async settings() {
            if(!this._settings) this._settings = this.client.transactionHandler.send({ provider: 'mongodb', request: { collection: 'guilds', type: 'findOne', query: { guildId: this.id } } });
            if(this._settings instanceof Promise) this._settings = await this._settings || null;
            if(!this._settings) this._settings = { guildId: this.id, ...this.client.defaultConfig };
            return this._settings;
        }

        //Fetch and cache perms
        async permissions() {
            if(!this._permissions) this._permissions = this.client.transactionHandler.send({ provider: 'mongodb', request: { collection: 'permissions', type: 'findOne', query: { guildId: this.id } } });
            if(this._permissions instanceof Promise) this._permissions = await this._permissions || null;
            if(!this._permissions) this._permissions = { guildId: this.id };
            return this._permissions;
        }

        /* Settings Wrapper */

        async _deleteSettings() { //Delete whole entry - remove
            try {
                await this.client.transactionHandler.send({
                    provider: 'mongodb',
                    request: {
                        type: 'remove',
                        collection: 'guilds',
                        query: {
                            guildId: this.id
                        }
                    }
                });
                this._settings = this.client.defaultConfig;
                this._storageLog(`Database Delete (guild:${this.id}).`);
            } catch(error) {
                this._storageError(error);
            }
            return true;
        }

        async _updateSettings(data) { //Update property (upsert true) - updateOne
            try {
                await this.client.transactionHandler.send({
                    provider: 'mongodb',
                    request: {
                        type: 'updateOne',
                        collection: 'guilds',
                        query: {
                            guildId: this.id
                        },
                        data
                    }
                });
                this._settings = { 
                    ...this._settings,
                    ...data
                };
                this._storageLog(`Database Update (guild:${this.id}).`);
            } catch(error) {
                this._storageError(error);
            }
            return true;
        }

        async _removeSettings(value) { //Remove property
            if(this.client.defaultConfig[value]) {
                await this._updateSettings({ [value]: this.client.defaultConfig[value] });
                return undefined;
            }
            try {
                await this.client.transactionHandler.send({
                    provider: 'mongodb',
                    request: {
                        type: 'removeProperty',
                        collection: 'guilds',
                        query: {
                            guildId: this.id
                        },
                        data: [
                            value
                        ]
                    }
                });
                this._storageLog(`Database Remove (guild:${this.id}).`);
                delete this._settings[value];
            } catch(error) {
                this._storageError(error);
            }
            return true;
        }  

        /* Language Formatting */

        format(index, parameters = {}, code = false) {

            let language = 'en_us';
            if (this._settings.locale) language = this._settings.locale;

            parameters.prefix = this.prefix;
            let template = this.client.localeLoader.template(language, index);

            if (!template) {
                return `**Missing language index \`${language} [${index}]\` in languages. Contact a bot developer about this.**`;
            }

            for (const [param, val] of Object.entries(parameters)) {
                template = template.replace(new RegExp(`{${escapeRegex(param.toLowerCase())}}`, 'giu'), val);
            }

            if (code) {
                try {
                    // eslint-disable-next-line no-eval
                    template = eval(template);
                } catch (error) {
                    this.client.logger.error(`Error in locale ${language}:${index} while executing code.\n${error.stack || error}`);
                }
            }

            return template;
            
        }

        /* Resolver Shortcuts */

        async resolveMembers(members, strict = false) {

            return this.client.resolver.resolveMembers(members, this, strict);

        }

        async resolveMember(member, strict) {

            return this.client.resolver.resolveMembers(member, this, strict);

        }

        resolveChannels(channels, strict = false) {

            return this.client.resolver.resolveChannels(channels, this, strict);

        }

        resolveChannel(channel, strict) {

            return this.client.resolver.resolveChannel(channel, this, strict);

        }

        async resolveRoles(roles, strict = false) {

            return this.client.resolver.resolveRoles(roles, this, strict);

        }

        async resolveRole(role, strict) {
            
            return this.client.resolver.resolveRole(role, this, strict);

        }


        /* Logging */

        _storageLog(log) {
            this.client.logger.debug(log);
        }

        _storageError(error) {
            this.client.logger.error(`Database Error (guild:${this.id}) : \n${error.stack || error}`);
        }

        get prefix() {
            return this._settings.prefix
                || this.client._options.bot.prefix;
        }
        
        get premium() { //GUILD SETTINGS MUST BE FETCHED
            return this._settings.premium; 
        }

    }

    return ExtendedGuild;

});

module.exports = Guild;