export default class ChannelController{

	/* (1) Construct default attributes
	*
	---------------------------------------------------------*/
	constructor(){

		/* (1) Set default active channel */
		this.current = null;

		/* (2) Initialize channel list */
		this.list = [];

		/* (3) Current channel buffer */
		this._buffer = {};


	}


	/* (2) Channel navigation
	*
	* @channel_id<int>					Channel id (NULL uses get())
	*
	* @return status<boolean>			Whether the navigation has been successful
	*
	---------------------------------------------------------*/
	nav(channel_id=null){

		console.log(`channel.nav(${channel_id})`);

		/* (1) Get channel data */
		var channel = this.get(channel_id);

		/* (2) Navigate vue-router */
		gs.get.router.push(`/channel/${channel.link}`);

		/* (3) Update current id */
		this.current = channel.id;

		/* (4) Update buffer */
		this._buffer = {};
		for( let c of this.list )
			if( c.id === this.current )
				this._buffer = c;

		/* (5) Load rooms */
		gs.get.room.fetch();

		/* (6) Log channel */
		console.log(`[channel.current] ${channel.link} (${channel.label})`);

		return true;
	}


	/* (3) Dump/Update channel data
	*
	* @channels<array>					Channels data
	*
	* @return udpated<boolean>			Whether channels have been updated
	*
	---------------------------------------------------------*/
	dump(channels){
		console.log(`channel.dump([${channels instanceof Array?channels.length:0}])`);

		/* (1) Check @channels type */
		if( !(channels instanceof Array) )
			return false;

		/* (2) Clear list () */
		this.list.splice(0);

		/* (3) Apply new channels */
		for(let c of channels){

			// add 'users' field (will be filled by GET channel/cid)
			c.users = [];

			this.list.push(c);

		}

		return true;

	}


	/* (4) Get channel data
	*
	* @channel_id<int>					Channel ID
	*									NULL: current channel || from URL (and set current)
	*
	* @return channel<array>			Channel data
	*
	---------------------------------------------------------*/
	get(channel_id=null){
		// console.log(`channel.get(${channel_id})`);

		if( channel_id === null ){

			/* (1) Get @current channel
			---------------------------------------------------------*/
			/* (1) If @current is set */
			if( !isNaN(this.current) ){

				/* (2) Return matching id in list */
				for( let c of this.list ){

					if( c.id === this.current )
						return c; // exit point

				}

			}


			/* (2) Get from URL
			---------------------------------------------------------*/
			/* (1) If vue-router has @link param */
			if( gs.get.router.history.current.params.link ){

				/* (2) Extract @link */
				let link = gs.get.router.history.current.params.link;

				/* (3) Return matching link in list */
				for( let c of this.list ){

					if( c.link === link ){

						this.current = c.id; // set @current
						return c;           // exit point

					}

				}

			}

		}


		/* (3) Get channel data
		---------------------------------------------------------*/
		/* (1) Return channel matching id */
		for( let c of this.list )
			if( c.id === channel_id )
				return c; // exit point

		/* (2) Return default: if ID not found */
		this.current = this.list[0].id;
		return this.list[0];

	}




	/* (6) Fetch channel data
	*
	---------------------------------------------------------*/
	fetch(){


		api.call('GET /channel', {}, function(rs){

			/* (1) Check errors */
			if( rs.error !== 0 || rs.channels == null )
				return;

			/* (2) Dump data */
			this.dump(rs.channels);

			/* (3) Find if @link matches */
			var redirect_id = null;
			for( let c of this.list ){

				if( c.link === window.initial_link ){
					redirect_id = c.id;
					break;
				}

			}

			/* (4) Emulate navigatation from URL */
			console.log(`[restore.channel] ${redirect_id}`);
			this.nav(redirect_id);

		}.bind(this), auth.token);
	}


	/* (7) Create a new channel
	*
	* @name<String>						channel name
	* @link<String>						channel URI link
	*
	* @return created<bool>				Whether the channel has been created
	*
	---------------------------------------------------------*/
	create(name=null, link=null){

		/* (1) Manage invalid @link */
		if( typeof link !== 'string' )
			return false;

		/* (2) Manage invalid @name */
		if( typeof name !== 'string' )
			return false;

		/* (3) Try to create room in API */
		api.call('POST /channel', { link: link, name: name }, function(rs){

			/* (1) Manage error */
			if( rs.error !== 0 || rs.cid == null )
				return false;

			/* (2) Reload channel list */
			this.fetch();

			/* (3) Hide popup */
			gs.get.popup.hide();

		}, auth.token);

		return true;

	}

}