import XHRClientDriver from './client/xhr.js'

export default class APIClient{



	/* (1) Constructs an API client manager
	*
	*
	* @return http_url<String>			Built http_url
	*
	---------------------------------------------------------*/
	constructor(_hostname){

		this.xhr_driver = new XHRClientDriver(_hostname, true);

	}



	/* Server Transaction
	*
	* @param _path<String>				target path (format "HTTP_METHOD uri/uri/uri")
	* @param _form<Object>				formdata object (as raw object)
	* @param _callback<Function>		Response callback
	* @param _token<String>				[OPT] http token
	*
	***************************************************************************************************
	*
	* @usecase
	*	1.		api.call(
	*	2.			'PUT newspaper/article/4'
	*	3.			{ content: "new content" },
	*	4.			(r) => alert(r.error),
	*	5.			'sometoken'
	*	6.		);
	*
	*/
	call(_path, _form, _callback, _token=null){


		/* (1) Argument management
		---------------------------------------------------------*/
		/* (1) Set default callback if @callback not callable */
		if( !(_callback instanceof Function) )
			_callback = function(r){ console.warn('The API callback function is missing, default callback set.', 'Response', r); };

		var persist = { received: false };

		/* (2) Bind callbacks */
		this.xhr_driver.onreceive = function(_response){

			this.received = true;

			/* Try to parse JSON */
			try{ _response = JSON.parse(_response); }catch(e){ _callback({error: -2}); }

			/* If authentication failed -> logout user*/
			if( typeof _response.error === 'number' && _response.error === -1 ){
				auth.token = null;
				document.location = '';
				return;
			}

			/* Launch @_callback with response */
			_callback(_response);

		}.bind(persist);

		this.xhr_driver.onclose = function(){ !this.received && _callback({ error: -3 }); }.bind(persist);


		return this.xhr_driver.send({
			path:       _path,
			form:       _form,
			http_token: _token
		});

	}


}