/*
 * Copyright (C) by Jocelyn Turcotte <jturcotte@woboq.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 * for more details.
 */

#import "SyncClientProxy.h"

@protocol ServerProtocol <NSObject>
- (void)registerClient:(id)client;
@end

@interface SyncClientProxy ()
- (void)registerTransmitter:(id)tx;
@end

@implementation SyncClientProxy

- (instancetype)initWithDelegate:(id)arg1 serverName:(NSString*)serverName
{
	self = [super init];

	self.delegate = arg1;
	_serverName = serverName;
	_remoteEnd = nil;

	return self;
}

#pragma mark - Connection setup

- (void)start
{
	if (_remoteEnd)
		return;
	
	// Lookup the server connection
	NSConnection *conn = [NSConnection connectionWithRegisteredName:_serverName host:nil];
	
	if (!conn) {
		// Could not connect to the sync client
		[self scheduleRetry];
		return;
	}
	
	[[NSNotificationCenter defaultCenter] addObserver:self
		selector:@selector(connectionDidDie:)
		name:NSConnectionDidDieNotification
		object:conn];
	
	NSDistantObject <ServerProtocol> *server = (NSDistantObject <ServerProtocol> *)[conn rootProxy];
	assert(server);
	
	// This saves a few Mach messages, enable "Distributed Objects" in the scheme's Run diagnostics to watch
	[server setProtocolForProxy:@protocol(ServerProtocol)];
	
	// Send an object to the server to act as the channel rx, we'll receive the tx through registerTransmitter
	[server registerClient:self];
}

- (void)registerTransmitter:(id)tx;
{
	// The server replied with the distant object that we will use for tx
	_remoteEnd = (NSDistantObject <ChannelProtocol> *)tx;
	[_remoteEnd setProtocolForProxy:@protocol(ChannelProtocol)];

	// Everything is set up, start querying
	[self askOnSocket:@"" query:@"GET_STRINGS"];
}

- (void)scheduleRetry
{
	[NSTimer scheduledTimerWithTimeInterval:5 target:self selector:@selector(start) userInfo:nil repeats:NO];
}

- (void)connectionDidDie:(NSNotification*)notification
{
#pragma unused(notification)
	_remoteEnd = nil;
	[_delegate connectionDidDie];
	
	[self scheduleRetry];
}

#pragma mark - Communication logic

- (void)sendMessage:(NSData*)msg
{
	NSString *answer = [[NSString alloc] initWithData:msg encoding:NSUTF8StringEncoding];

	// Cut the trailing newline
	answer = [answer substringToIndex:[answer length] - 1];
	NSArray *chunks = [answer componentsSeparatedByString: @":"];

	if( [[chunks objectAtIndex:0] isEqualToString:@"STATUS"] ) {
		NSString *result = [chunks objectAtIndex:1];
		NSString *path = [chunks objectAtIndex:2];
		if( [chunks count] > 3 ) {
			for( int i = 2; i < [chunks count]-1; i++ ) {
				path = [NSString stringWithFormat:@"%@:%@",
						path, [chunks objectAtIndex:i+1] ];
			}
		}
		[_delegate setResultForPath:path result:result];
	} else if( [[chunks objectAtIndex:0] isEqualToString:@"UPDATE_VIEW"] ) {
		NSString *path = [chunks objectAtIndex:1];
		[_delegate reFetchFileNameCacheForPath:path];
	} else if( [[chunks objectAtIndex:0 ] isEqualToString:@"REGISTER_PATH"] ) {
		NSString *path = [chunks objectAtIndex:1];
		[_delegate registerPath:path];
	} else if( [[chunks objectAtIndex:0 ] isEqualToString:@"UNREGISTER_PATH"] ) {
		NSString *path = [chunks objectAtIndex:1];
		[_delegate unregisterPath:path];
	} else if( [[chunks objectAtIndex:0 ] isEqualToString:@"GET_STRINGS"] ) {
		// BEGIN and END messages, do nothing.
	} else if( [[chunks objectAtIndex:0 ] isEqualToString:@"STRING"] ) {
		[_delegate setString:[chunks objectAtIndex:1] value:[chunks objectAtIndex:2]];
	} else {
		NSLog(@"SyncState: Unknown command %@", [chunks objectAtIndex:0]);
	}
}

- (void)askOnSocket:(NSString*)path query:(NSString*)verb
{
	NSString *query = [NSString stringWithFormat:@"%@:%@\n", verb,path];

	@try {
		[_remoteEnd sendMessage:[query dataUsingEncoding:NSUTF8StringEncoding]];
	} @catch(NSException* e) {
		// Do nothing and wait for connectionDidDie
	}
}

- (void)askForIcon:(NSString*)path isDirectory:(BOOL)isDir
{
	NSString *verb = isDir ? @"RETRIEVE_FOLDER_STATUS" : @"RETRIEVE_FILE_STATUS";
	[self askOnSocket:path query:verb];
}

@end