type LangObj = { [keys:string]: LangObj | string }
type LangObjWhole = { [langid:string]: LangObj }

const LANG: LangObjWhole = {

    en: {

        main: {
            login: 'Logged in as {user}'
        },

        discord: {
            botRestart: 'The bot has just restarted, anybody previously in the queue has been reset',
            create: 'A queue for teams of {teamsize} has been created',
            close: 'Queue has been closed',
            join: 'Joined the queue',
            leave: 'Left the queue'
        },

        error: {

            main: {
                missingToken: 'Missing Discord Token, please enter the bot token into the token file'
            },

            discord: {
                noQueue: 'There is not an active queue in this channel, type `/open` to create one',
                noChannel: 'Unable to find channel {channelId} for teams of {teamsize}',
                noCreate: 'There is already an active queue in this channel for teams of ${teamsize}',
                inQueue: 'You are already in the queue',
                notInQueue: 'You aren\'t in the queue',
                notMod: 'Member is not a moderator'
            },

            general: {
                noMember: 'Unable to retrieve guild member information, please try again',
                noChannel: 'Unable to retrieve text channel information, please try again'
            },

            api: {
                noUser: 'Unable to find user'
            }

        }

    }

}

export namespace Lang {

    var LANGID = 'en';
    if (!(LANGID in LANG))
        throw 'language id does not exist';

    export function setLang(langid: string) {
        if (langid in LANG)
            LANGID = langid;
        else
            throw 'language id does not exist';
    }

    function template(str: string, args: {[keys: string]: string}): string {

        return str.replace(/{\w+}/g, str => {

            let key = str.substring(1, str.length-1);

            if (key in args)
                return args[key];

            return key;

        });

    }

    /**
     * reads language json
     * @param id ex: discord.error.noActiveQueue
     * @returns language value, defaults to `id` parameter
     */
    export function get(id: string, args: {[keys: string]: string} = {}): string {//discord.error.noActiveQueue
        
        let keySpl = id.split('.').map(k => k.trim()).filter(k => k);

        let finding = LANG[LANGID];

        for (let key of keySpl) {

            if (key in finding) {

                let found = finding[key];

                if (typeof found === 'string')
                    return template(found, args);

                finding = found;

            } else
                break;
            
        }

        return id;
    }
        
}