/*

	Copyright (c) 2020, 2023, The Unified Company.

	This code is part of Unify.

	This program is free software; you can redistribute it and/or modify
	it under the terms of the ESA Software Community License - Strong Copyleft,

	https://unifyjs.org 

*/

import WebSocket, {WebSocketServer} 	from 'ws';

import database                     	from '../server/database.js';

import querySQL 											from '../unify/querySQL.js';

import readline 											from 'readline';

import socketMessage 									from '../unify/socketMessage.js';

import fs 														from 'fs';

var clusterClientID = 0;


//database.createTable( "sync_client" );

database.addColumn( "original_id", "INTEGER", "sync_client" );

database.addColumn( "server_id", "INTEGER", "sync_client" );

database.addColumn( "queryString", "TEXT", "sync_client" );

database.addColumn( "columnValues", "TEXT", "sync_client" );

database.addColumn( "operation", "TEXT", "sync_client" );

database.addColumn( "clusterClientID", "INTEGER", "sync_client" );

database.addColumn( "synced", "BOOLEAN", "sync_client" );




export default class syncClient{

	clusterClientID				= 5;

	syncServerAddress 		= "ws://localhost:4422";

	mode 									= "sync";

	constructor( mode ) {

		if( mode ) {

			this.mode = mode;

		}

		this.connect();

	

	}

	emptyTable() {

		database.database.prepare( "DELETE from sync_client" ).run()

	}

	hearthBeat() {

		//if( this.socket.readyState != 0 )
		
		//console.log("perform hearthBeat");

		var message 									= new socketMessage();

		message.type									= "add_sqlite_operation";

		message.unsynced 							= this.getUnsynced();

		message.clusterClientID				= this.clusterClientID;

		message.lastID 								= this.getLastID();

		//console.log("getUnsynced", this.getUnsynced());

		var unsynced 	= this.getUnsynced()

		if(unsynced.length != 0) {

			console.log( unsynced );

			console.log( "unsynced", unsynced.length );
			
		}



		if( this.socket ) {

			this.socket.send( JSON.stringify( message ) );

		}


		var that  = this;

	    setTimeout(function() {

	     	that.hearthBeat();

	    }, 1000);



	}

	async connect(){

		this.socket = new WebSocket( this.syncServerAddress, {

			perMessageDeflate: false

		});

		var syncClient 	= this;

		this.socket.on('error', function open( error ) {

			syncClient.onError();

		});

		this.socket.on('close', function open( error ) {

			syncClient.onClose();
			
		});

		this.socket.on('open', function open( socket ) {

			syncClient.onOpen();

		});

		this.socket.on('message', function message( data ) {

			syncClient.onMessage( data );

		});

	}

	getLastID() {

		var query = new querySQL( );
		
		query.type	= "select";

		query.table	= "sync_client";

		query.order	= ["server_id Desc LIMIT 1"];

		query.find( "clusterClientID", this.clusterClientID , "!=" );

		query.sync = false;



		var result = database.query( query ); 

		if( result.length == 0 ) {

			return 0;

		}

		return result[0].server_id;

	}

	getUnsynced() {

		var query = new querySQL( );
		
		query.type	= "select";
		query.table	= "sync_client";
		query.order	= ["id"];// Desc LIMIT 1

		query.find( "clusterClientID", this.clusterClientID , "=" );

		query.find( "synced", false );

		query.sync	= false;

		var result = database.query( query ); 

		return result;

	}

	sendMessage( queryString, inputQuery, original_id ) {

		//   !!! console.log("syncClient: send message is performed");
		
		if( !original_id ) {

			return true;

		}

		var query = new querySQL( );


		query.type  = "insert";

		query.table = "sync_client";


		query.setValue( "original_id", original_id );

		query.setValue( "queryString", queryString );

		query.setValue( "columnValues", JSON.stringify( inputQuery.getValues() ) ); 

		query.setValue( "clusterClientID", this.clusterClientID ); 

		query.setValue( "operation", inputQuery.type ); 

		query.setValue( "synced", false ); 


		query.sync	= false;


		var result = database.query( query ); 

	}



	onError() {



	}

	onClose() {

	  //console.log('Socket is closed. Reconnect will be attempted in 1 second.', this.mode);

	  switch( this.mode ) {

			case "download_database":

				return true;

			break;

			default:

				var that = this;

				setTimeout(function() {

				
				that.connect();

				}, 3000);

		}

	}

	onOpen() {

		switch( this.mode ) {

			case "sync":

				this.hearthBeat();

			break;

			case "download_database":

				var message 									= new socketMessage();

				message.type									= "download_database";

				console.log("Downloading most recent database from Sync server, Please wait...");

				this.socket.send( JSON.stringify( message ) );

			break;


		}
			
	}

	onMessage( data ) {

		var parseData = JSON.parse( data );

		

		switch( parseData.name ) {

			case "connected":

				//clusterClientID = parseData.clientID;

			break;

			case "upload_database":

				//console.log("binary", parseData.binary);

				console.log("Recieved most recent binary of database, Now writing to disk...");

				fs.writeFileSync( "./framework/db/uploaded_db.sqlite", Buffer.from( parseData.binary.data )  );

				this.socket.close()

			break;

			case "updateSyncClient":

				// update synced rows
				var synced = parseData.synced;

				for (var i = 0; i < synced.length; i++) {

					var row 		= synced[i];

					var query 		= new querySQL( );


					query.type  = "update";

					query.table = "sync_client";

					query.setValue( "synced", true );

					//query.setValue( "server_id", row.server_id );


					query.find( "id", row.id, "=" );


					query.sync = false;


					database.query( query );

				}

			//	console.log("set synced of previouse added rows to true:	", synced.length);


				// add new rows
				var rows = parseData.rows;



				//console.log("adding missing rows: 				", rows.length);

				for (var i = 0; i < rows.length; i++) {

					var row = rows[i];

					//console.log(row);

					// --

					// perform real query here

					var columnArray 	= JSON.parse( row.columnValues );

					var query 			= new querySQL( );

					query.type			= row.operation;

					for (var a = 0; a < columnArray.length; a++) {

						var column = new Array();
						
						column.name 	= false;
						column.value	= columnArray[a];

						query.values.push( column );

					}

					query.sync = false;

					database.executeQuery( row.queryString, query );


					// ---


					var query = new querySQL( );

					query.type  = "insert";

					query.table = "sync_client";

					query.setValue( "original_id", row.original_id );

					query.setValue( "queryString", row.queryString );

					query.setValue( "columnValues", row.columnValues ); 

					query.setValue( "operation", row.operation ); 

					query.setValue( "clusterClientID", row.clusterClientID ); 

					query.setValue( "server_id", row.id ); 

					query.setValue( "synced", true );



					query.sync = false;



					var result = database.query( query );

				}

				

			break;
		}



	}


}


/*
var syncClientManager = new syncClient();


readline.emitKeypressEvents( process.stdin );
process.stdin.setRawMode(true);

process.stdin.on('keypress', (str, key) => {
  //console.log(str)
  //console.log(key)
  console.log(key);

  if(key.name == "c") {

  	process.exit();

  }
  	

	var exampleQuery = new querySQL( );

	exampleQuery.type  = "insert";

	exampleQuery.table = "comment";

	exampleQuery.setValue( "author_id", 1123 );



	var insert = database.query( exampleQuery );

	var queryString	= database.query( exampleQuery, false );

	syncClientManager.sendMessage( queryString, exampleQuery, insert.lastInsertRowid );

})


*/