//
//  TSDatabaseView.m
//  TextSecureKit
//
//  Created by Frederic Jacobs on 17/11/14.
//  Copyright (c) 2014 Open Whisper Systems. All rights reserved.
//

#import "TSDatabaseView.h"

#import <YapDatabase/YapDatabaseView.h>

#import "OWSDevice.h"
#import "TSIncomingMessage.h"
#import "TSStorageManager.h"
#import "TSThread.h"

NSString *TSInboxGroup   = @"TSInboxGroup";
NSString *TSArchiveGroup = @"TSArchiveGroup";

NSString *TSUnreadIncomingMessagesGroup = @"TSUnreadIncomingMessagesGroup";
NSString *TSSecondaryDevicesGroup = @"TSSecondaryDevicesGroup";

NSString *TSThreadDatabaseViewExtensionName  = @"TSThreadDatabaseViewExtensionName";
NSString *TSMessageDatabaseViewExtensionName = @"TSMessageDatabaseViewExtensionName";
NSString *TSUnreadDatabaseViewExtensionName  = @"TSUnreadDatabaseViewExtensionName";
NSString *TSSecondaryDevicesDatabaseViewExtensionName = @"TSSecondaryDevicesDatabaseViewExtensionName";

@implementation TSDatabaseView

+ (BOOL)registerUnreadDatabaseView {
    YapDatabaseView *unreadView =
        [[TSStorageManager sharedManager].database registeredExtension:TSUnreadDatabaseViewExtensionName];
    if (unreadView) {
        return YES;
    }

    YapDatabaseViewGrouping *viewGrouping = [YapDatabaseViewGrouping
        withObjectBlock:^NSString *(
            YapDatabaseReadTransaction *transaction, NSString *collection, NSString *key, id object) {
          if ([object isKindOfClass:[TSIncomingMessage class]]) {
              TSIncomingMessage *message = (TSIncomingMessage *)object;
              if (message.read == NO) {
                  return message.uniqueThreadId;
              }
          }
          return nil;
        }];

    YapDatabaseViewSorting *viewSorting = [self messagesSorting];

    YapDatabaseViewOptions *options = [[YapDatabaseViewOptions alloc] init];
    options.isPersistent            = YES;
    options.allowedCollections =
        [[YapWhitelistBlacklist alloc] initWithWhitelist:[NSSet setWithObject:[TSInteraction collection]]];

    YapDatabaseView *view =
        [[YapDatabaseView alloc] initWithGrouping:viewGrouping sorting:viewSorting versionTag:@"1" options:options];

    return
        [[TSStorageManager sharedManager].database registerExtension:view withName:TSUnreadDatabaseViewExtensionName];
}

+ (BOOL)registerThreadDatabaseView {
    YapDatabaseView *threadView =
        [[TSStorageManager sharedManager].database registeredExtension:TSThreadDatabaseViewExtensionName];
    if (threadView) {
        return YES;
    }

    YapDatabaseViewGrouping *viewGrouping = [YapDatabaseViewGrouping
        withObjectBlock:^NSString *(
            YapDatabaseReadTransaction *transaction, NSString *collection, NSString *key, id object) {
          if ([object isKindOfClass:[TSThread class]]) {
              TSThread *thread = (TSThread *)object;
              if (thread.archivalDate) {
                  return ([self threadShouldBeInInbox:thread]) ? TSInboxGroup : TSArchiveGroup;
              } else if (thread.archivalDate) {
                  return TSArchiveGroup;
              } else {
                  return TSInboxGroup;
              }
          }
          return nil;
        }];

    YapDatabaseViewSorting *viewSorting = [self threadSorting];

    YapDatabaseViewOptions *options = [[YapDatabaseViewOptions alloc] init];
    options.isPersistent            = NO;
    options.allowedCollections =
        [[YapWhitelistBlacklist alloc] initWithWhitelist:[NSSet setWithObject:[TSThread collection]]];

    YapDatabaseView *databaseView =
        [[YapDatabaseView alloc] initWithGrouping:viewGrouping sorting:viewSorting versionTag:@"1" options:options];

    return [[TSStorageManager sharedManager]
                .database registerExtension:databaseView
                                   withName:TSThreadDatabaseViewExtensionName];
}

+ (BOOL)registerBuddyConversationDatabaseView {
    if ([[TSStorageManager sharedManager].database registeredExtension:TSMessageDatabaseViewExtensionName]) {
        return YES;
    }

    YapDatabaseViewGrouping *viewGrouping = [YapDatabaseViewGrouping
        withObjectBlock:^NSString *(
            YapDatabaseReadTransaction *transaction, NSString *collection, NSString *key, id object) {
          if ([object isKindOfClass:[TSInteraction class]]) {
              return ((TSInteraction *)object).uniqueThreadId;
          }
          return nil;
        }];

    YapDatabaseViewSorting *viewSorting = [self messagesSorting];

    YapDatabaseViewOptions *options = [[YapDatabaseViewOptions alloc] init];
    options.isPersistent            = YES;
    options.allowedCollections =
        [[YapWhitelistBlacklist alloc] initWithWhitelist:[NSSet setWithObject:[TSInteraction collection]]];

    YapDatabaseView *view =
        [[YapDatabaseView alloc] initWithGrouping:viewGrouping sorting:viewSorting versionTag:@"1" options:options];

    return
        [[TSStorageManager sharedManager].database registerExtension:view withName:TSMessageDatabaseViewExtensionName];
}


/**
 *  Determines whether a thread belongs to the archive or inbox
 *
 *  @param thread TSThread
 *
 *  @return Inbox if true, Archive if false
 */

+ (BOOL)threadShouldBeInInbox:(TSThread *)thread {
    NSDate *lastMessageDate = thread.lastMessageDate;
    NSDate *archivalDate    = thread.archivalDate;
    if (lastMessageDate && archivalDate) { // this is what is called
        return ([lastMessageDate timeIntervalSinceDate:archivalDate] > 0)
                   ? YES
                   : NO; // if there hasn't been a new message since the archive date, it's in the archive. an issue is
                         // that empty threads are always given with a lastmessage date of the present on every launch
    } else if (archivalDate) {
        return NO;
    }

    return YES;
}

+ (YapDatabaseViewSorting *)threadSorting {
    return [YapDatabaseViewSorting withObjectBlock:^NSComparisonResult(YapDatabaseReadTransaction *transaction,
                                                                       NSString *group,
                                                                       NSString *collection1,
                                                                       NSString *key1,
                                                                       id object1,
                                                                       NSString *collection2,
                                                                       NSString *key2,
                                                                       id object2) {
      if ([group isEqualToString:TSArchiveGroup] || [group isEqualToString:TSInboxGroup]) {
          if ([object1 isKindOfClass:[TSThread class]] && [object2 isKindOfClass:[TSThread class]]) {
              TSThread *thread1 = (TSThread *)object1;
              TSThread *thread2 = (TSThread *)object2;

              return [thread1.lastMessageDate compare:thread2.lastMessageDate];
          }
      }

      return NSOrderedSame;
    }];
}

+ (YapDatabaseViewSorting *)messagesSorting {
    return [YapDatabaseViewSorting withObjectBlock:^NSComparisonResult(YapDatabaseReadTransaction *transaction,
                                                                       NSString *group,
                                                                       NSString *collection1,
                                                                       NSString *key1,
                                                                       id object1,
                                                                       NSString *collection2,
                                                                       NSString *key2,
                                                                       id object2) {
      if ([object1 isKindOfClass:[TSInteraction class]] && [object2 isKindOfClass:[TSInteraction class]]) {
          TSInteraction *message1 = (TSInteraction *)object1;
          TSInteraction *message2 = (TSInteraction *)object2;

          NSDate *date1 = [self localTimeReceiveDateForInteraction:message1];
          NSDate *date2 = [self localTimeReceiveDateForInteraction:message2];

          NSComparisonResult result = [date1 compare:date2];

          // NSDates are only accurate to the second, we might want finer precision
          if (result != NSOrderedSame) {
              return result;
          }

          if (message1.timestamp > message2.timestamp) {
              return NSOrderedDescending;
          } else if (message1.timestamp < message2.timestamp) {
              return NSOrderedAscending;
          } else {
              return NSOrderedSame;
          }
      }

      return NSOrderedSame;
    }];
}

+ (BOOL)registerSecondaryDevicesDatabaseView
{
    YapDatabaseView *existingView =
        [[TSStorageManager sharedManager].database registeredExtension:TSSecondaryDevicesDatabaseViewExtensionName];
    if (existingView) {
        return YES;
    }

    YapDatabaseViewGrouping *viewGrouping =
        [YapDatabaseViewGrouping withObjectBlock:^NSString *_Nullable(YapDatabaseReadTransaction *_Nonnull transaction,
            NSString *_Nonnull collection,
            NSString *_Nonnull key,
            id _Nonnull object) {
            if ([object isKindOfClass:[OWSDevice class]]) {
                OWSDevice *device = (OWSDevice *)object;
                if (![device isPrimaryDevice]) {
                    return TSSecondaryDevicesGroup;
                }
            }
            return nil;
        }];

    YapDatabaseViewSorting *viewSorting =
        [YapDatabaseViewSorting withObjectBlock:^NSComparisonResult(YapDatabaseReadTransaction *_Nonnull transaction,
            NSString *_Nonnull group,
            NSString *_Nonnull collection1,
            NSString *_Nonnull key1,
            id _Nonnull object1,
            NSString *_Nonnull collection2,
            NSString *_Nonnull key2,
            id _Nonnull object2) {

            if ([object1 isKindOfClass:[OWSDevice class]] && [object2 isKindOfClass:[OWSDevice class]]) {
                OWSDevice *device1 = (OWSDevice *)object1;
                OWSDevice *device2 = (OWSDevice *)object2;

                return [device2.createdAt compare:device1.createdAt];
            }

            return NSOrderedSame;
        }];

    YapDatabaseViewOptions *options = [YapDatabaseViewOptions new];
    options.isPersistent = YES;

    NSSet *deviceCollection = [NSSet setWithObject:[OWSDevice collection]];
    options.allowedCollections = [[YapWhitelistBlacklist alloc] initWithWhitelist:deviceCollection];

    YapDatabaseView *view =
        [[YapDatabaseView alloc] initWithGrouping:viewGrouping sorting:viewSorting versionTag:@"3" options:options];

    return [[TSStorageManager sharedManager].database registerExtension:view
                                                               withName:TSSecondaryDevicesDatabaseViewExtensionName];
}

+ (NSDate *)localTimeReceiveDateForInteraction:(TSInteraction *)interaction {
    NSDate *interactionDate = interaction.date;

    if ([interaction isKindOfClass:[TSIncomingMessage class]]) {
        TSIncomingMessage *message = (TSIncomingMessage *)interaction;

        if (message.receivedAt) {
            interactionDate = message.receivedAt;
        }
    }

    return interactionDate;
}

@end