//
//  MBIMBridge.m
//  MessagesBridge
//
//  Created by James Magahern on 11/12/18.
//  Copyright © 2018 James Magahern. All rights reserved.
//

#import "MBIMBridge.h"

#import <GCDWebServers/GCDWebServers.h>

#import <IMCore/IMCore.h>
#import <IMCore/IMCore_Private.h>

#import <IMFoundation/IMFoundation.h>
#import <IMFoundation/IMFoundation_Private.h>

static NSString *const MBIMBridgeToken = @"net.buzzert.MBIMBridge";

static NSString *const kAPIEndpointConversationList = @"conversations";
static NSString *const kAPIEndpointConversationContents = @"messages";
static NSString *const kAPIEndpointSendMessage = @"sendMessage";

@interface MBIMBridge (/* INTERNAL */)
@property (nonatomic, strong) GCDWebServer *webServer;

- (instancetype)_init;
@end

@implementation MBIMBridge

+ (instancetype)sharedInstance
{
    static dispatch_once_t onceToken;
    static __strong MBIMBridge *sharedBridge = nil;
    dispatch_once(&onceToken, ^{
        sharedBridge = [[MBIMBridge alloc] _init];
    });
    
    return sharedBridge;
}

- (instancetype)_init
{
    self = [super init];
    if (self) {
        [self registerForNotifications];
        [self startWebServer];
        
        [sDaemonController setDelegate:self];
        [sDaemonListener addHandler:self];
    }
    
    return self;
}

#pragma mark -
#pragma mark Connection

- (void)connect
{
    if (![sDaemonController hasListenerForID: MBIMBridgeToken]) {
        if (![sDaemonController addListenerID:MBIMBridgeToken capabilities:(kFZListenerCapFileTransfers | kFZListenerCapManageStatus | kFZListenerCapChats | kFZListenerCapMessageHistory | kFZListenerCapIDQueries | kFZListenerCapSendMessages)]) {
            NSLog(@"Failed to connect to imagent");
        }
    }
}

- (void)disconnect
{
    [sDaemonController removeListenerID:MBIMBridgeToken];
}

#pragma mark -
#pragma mark Notifications

- (void)registerForNotifications
{
    (void)[IMChatRegistry sharedInstance];
    
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_messageReceived:) name:IMChatMessageReceivedNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_chatRegistryDidLoad:) name:IMChatRegistryDidLoadNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(_chatItemsDidChange:) name:IMChatItemsDidChangeNotification object:nil];
    
    [[NSNotificationCenter defaultCenter] addObserverForName: IMChatRegistryUnreadCountChangedNotification
                                                      object: nil
                                                       queue: [NSOperationQueue mainQueue]
                                                  usingBlock:^(NSNotification *note) {
                                                      NSLog(@"Unread count changed: %d", (int)[[IMChatRegistry sharedInstance] unreadCount]);
                                                  }];
}

- (void)_messageReceived:(NSNotification *)notification
{
    NSLog(@"Received!");
    
    // Sending a message
    /*
    IMAccount *iMessageAccount = [[IMAccountController sharedInstance] bestAccountForService:[IMServiceImpl iMessageService]];
    IMHandle *handle = [[iMessageAccount arrayOfAllIMHandles] firstObject];
    
    NSAttributedString *replyAttrString = [[NSAttributedString alloc] initWithString:@"This is a test automated reply. Please ignore."];
    IMMessage *reply = [IMMessage fromMeIMHandle:handle withText:replyAttrString fileTransferGUIDs:@[] flags:kIMMessageFinished];
    
    IMChat *chat = [notification object];
    [chat sendMessage:reply];
    */
}

- (void)_chatRegistryDidLoad:(NSNotification *)notification
{
    NSLog(@"Loaded chat registry. %lu existing chats", (unsigned long)[sChatRegistry numberOfExistingChats]);
}

- (void)_chatItemsDidChange:(NSNotification *)notification
{
    NSLog(@"chat items changed: %@", notification);
}

- (BOOL)_sendMessage:(NSString *)messageBody toChatWithGUID:(NSString *)chatGUID
{
    IMAccount *iMessageAccount = [[IMAccountController sharedInstance] bestAccountForService:[IMServiceImpl iMessageService]];
    IMHandle *handle = [[iMessageAccount arrayOfAllIMHandles] firstObject];
    
    NSAttributedString *replyAttrString = [[NSAttributedString alloc] initWithString:messageBody];
    IMMessage *reply = [IMMessage fromMeIMHandle:handle withText:replyAttrString fileTransferGUIDs:@[] flags:kIMMessageFinished];
    
    IMChat *chat = [sChatRegistry existingChatWithGUID:chatGUID];
    if (!chat) {
        NSLog(@"Chat does not exist: %@", chatGUID);
        return NO;
    }
    
    [chat sendMessage:reply];

    return YES;
}

#pragma mark -
#pragma mark Web Server initialization

- (void)startWebServer
{
    [GCDWebServer setLogLevel:3];
    
    __auto_type __weak weakSelf = self;
    self.webServer = [[GCDWebServer alloc] init];
    [self.webServer addDefaultHandlerForMethod:@"GET"
                                  requestClass:[GCDWebServerRequest class]
                                  processBlock:^GCDWebServerResponse * _Nullable(__kindof GCDWebServerRequest * _Nonnull request) { return [weakSelf _handleWebServerRequest:request]; }];
    
    [self.webServer addDefaultHandlerForMethod:@"POST"
                                  requestClass:[GCDWebServerURLEncodedFormRequest class]
                                  processBlock:^GCDWebServerResponse * _Nullable(__kindof GCDWebServerRequest * _Nonnull request) { return [weakSelf _handleWebServerPOST:(GCDWebServerURLEncodedFormRequest *)request]; }];
    
    [self.webServer startWithPort:8080 bonjourName:nil];
}

- (GCDWebServerResponse *)_handleWebServerPOST:(__kindof GCDWebServerURLEncodedFormRequest * _Nonnull)request
{
    NSURLComponents *urlComponents = [NSURLComponents componentsWithURL:[request URL] resolvingAgainstBaseURL:NO];
    NSString *endpoint = [[urlComponents path] lastPathComponent];
    
    if ([endpoint isEqualToString:kAPIEndpointSendMessage]) {
        NSDictionary *args = [request arguments];
        
        NSString *guid = [args objectForKey:@"guid"];
        NSString *messageBody = [args objectForKey:@"body"];
        BOOL result = [self _sendMessage:messageBody toChatWithGUID:guid];
        if (result) {
            return [GCDWebServerDataResponse responseWithStatusCode:200];
        } else {
            return [GCDWebServerDataResponse responseWithStatusCode:500];
        }
    }
    
    return [GCDWebServerDataResponse responseWithStatusCode:404];
}

- (GCDWebServerResponse *)_handleWebServerRequest:(__kindof GCDWebServerRequest * _Nonnull)request
{
    NSURLComponents *urlComponents = [NSURLComponents componentsWithURL:[request URL] resolvingAgainstBaseURL:NO];
    NSString *endpoint = [[urlComponents path] lastPathComponent];
    
    if ([endpoint isEqualToString:kAPIEndpointConversationList]) {
        NSArray<IMChat *> *chats = [sChatRegistry allExistingChats];

        NSMutableArray *conversations = [NSMutableArray array];
        for (IMChat *chat in chats) {
            NSMutableDictionary *chatDict = [NSMutableDictionary dictionary];
            chatDict[@"guid"] = [chat guid];
            chatDict[@"displayName"] = [chat displayName];
            chatDict[@"date"] = GCDWebServerFormatRFC822([chat lastFinishedMessageDate]);
            
            [conversations addObject:chatDict];
        }
        
        return [GCDWebServerDataResponse responseWithJSONObject:conversations];
    }
    
    if ([endpoint isEqualToString:kAPIEndpointConversationContents]) {
        NSString *guid = nil;
        for (NSURLQueryItem *queryItem in [urlComponents queryItems]) {
            if ([[queryItem name] isEqualToString:@"guid"]) {
                guid = [queryItem value];
                break;
            }
        }
        
        if (!guid) {
            NSLog(@"No query item provided");
            return [GCDWebServerDataResponse responseWithStatusCode:500];
        }
        
        IMChat *chat = [sChatRegistry existingChatWithGUID:guid];
        if (!chat) {
            NSLog(@"Chat with guid: %@ not found", guid);
            return [GCDWebServerDataResponse responseWithStatusCode:500];
        }
        
        // Load messages
        [chat loadMessagesBeforeDate:[NSDate date] limit:50 loadImmediately:YES];
        
        NSMutableArray *messages = [NSMutableArray array];
        for (IMMessageItem *imMessage in [[chat chatItems] messages]) {
            NSMutableDictionary *messageDict = [NSMutableDictionary dictionary];
            messageDict[@"text"] = [[imMessage body] string];
            messageDict[@"date"] = GCDWebServerFormatRFC822([imMessage time]);
            messageDict[@"sender"] = [imMessage sender];
            [messages addObject:messageDict];
        }
        
        return [GCDWebServerDataResponse responseWithJSONObject:messages];
    }
    
    
    return [GCDWebServerDataResponse responseWithStatusCode:404];
}

#pragma mark -
#pragma mark Daemon lifecycle

- (void)daemonControllerWillConnect
{
    NSLog(@"About to connect to daemon");
}

- (void)daemonControllerDidConnect
{
    NSLog(@"Did connect to daemon");
    
    IMAccount *iMessageAccount = [[IMAccountController sharedInstance] bestAccountForService:[IMServiceImpl iMessageService]];
    if (iMessageAccount) {
        NSLog(@"iMessage account connected: %@", iMessageAccount);
    } else {
        NSLog(@"Was not able to connect to iMessage account");
    }
}

- (void)daemonControllerDidDisconnect
{
    NSLog(@"Did disconnect from daemon");
}

- (void)daemonConnectionLost
{
    NSLog(@"Connection lost to daemon");
}

@end