/*
 * Copyright 2017 Google
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import <FirebaseCore/FIRApp.h>
#import "FIRDatabaseReference.h"
#import <FirebaseCore/FIROptions.h>
#import "FUtilities.h"
#import "FNextPushId.h"
#import "FIRDatabaseQuery_Private.h"
#import "FValidation.h"
#import "FIRDatabaseReference_Private.h"
#import "FStringUtilities.h"
#import "FSnapshotUtilities.h"
#import "FIRDatabaseConfig.h"
#import "FIRDatabaseConfig_Private.h"
#import "FQueryParams.h"
#import "FIRDatabase.h"

@implementation FIRDatabaseReference

#pragma mark -
#pragma mark Constructors

- (id) initWithConfig:(FIRDatabaseConfig *)config {
    FParsedUrl* parsedUrl = [FUtilities parseUrl:[[FIRApp defaultApp] options].databaseURL];
    [FValidation validateFrom:@"initWithUrl:" validURL:parsedUrl];
    return [self initWithRepo:[FRepoManager getRepo:parsedUrl.repoInfo config:config] path:parsedUrl.path];
}

- (id) initWithRepo:(FRepo *)repo path:(FPath *)path {
    return [super initWithRepo:repo
                          path:path
                        params:[FQueryParams defaultInstance]
                 orderByCalled:NO
          priorityMethodCalled:NO];
}


#pragma mark -
#pragma mark Ancillary methods

- (nullable NSString *) key {
    if([self.path isEmpty]) {
        return nil;
    }
    else {
        return [self.path getBack];
    }
}

- (FIRDatabase *) database {
    return self.repo.database;
}

- (FIRDatabaseReference *) parent {
    FPath* parentPath = [self.path parent];
    FIRDatabaseReference * parent = nil;
    if (parentPath != nil ) {
        parent = [[FIRDatabaseReference alloc] initWithRepo:self.repo path:parentPath];
    }
    return parent;
}

- (NSString *) URL {
    FIRDatabaseReference * parent = [self parent];
    return parent == nil ? [self.repo description] : [NSString stringWithFormat:@"%@/%@", [parent description], [FStringUtilities urlEncoded:self.key]];
}

- (NSString *) description {
    return [self URL];
}

- (FIRDatabaseReference *) root {
    return [[FIRDatabaseReference alloc] initWithRepo:self.repo path:[[FPath alloc] initWith:@""]];
}

#pragma mark -
#pragma mark Child methods

- (FIRDatabaseReference *)childByAppendingPath:(NSString *)pathString {
    return [self child:pathString];
}

- (FIRDatabaseReference *)child:(NSString *)pathString {
    if ([self.path getFront] == nil) {
        // we're at the root
        [FValidation validateFrom:@"child:" validRootPathString:pathString];
    } else {
        [FValidation validateFrom:@"child:" validPathString:pathString];
    }
    FPath* path = [self.path childFromString:pathString];
    FIRDatabaseReference * firebaseRef = [[FIRDatabaseReference alloc] initWithRepo:self.repo path:path];
    return firebaseRef;
}

- (FIRDatabaseReference *) childByAutoId {
    [FValidation validateFrom:@"childByAutoId:" writablePath:self.path];

    NSString* name = [FNextPushId get:self.repo.serverTime];
    return [self child:name];
}

#pragma mark -
#pragma mark Basic write methods

- (void) setValue:(id)value {
    [self setValueInternal:value andPriority:nil withCompletionBlock:nil from:@"setValue:"];
}

- (void) setValue:(id)value withCompletionBlock:(fbt_void_nserror_ref)block {
    [self setValueInternal:value andPriority:nil withCompletionBlock:block from:@"setValue:withCompletionBlock:"];
}

- (void) setValue:(id)value andPriority:(id)priority {
    [self setValueInternal:value andPriority:priority withCompletionBlock:nil from:@"setValue:andPriority:"];
}

- (void) setValue:(id)value andPriority:(id)priority withCompletionBlock:(fbt_void_nserror_ref)block {
    [self setValueInternal:value andPriority:priority withCompletionBlock:block from:@"setValue:andPriority:withCompletionBlock:"];
}

- (void) setValueInternal:(id)value andPriority:(id)priority withCompletionBlock:(fbt_void_nserror_ref)block from:(NSString*)fn {
    [FValidation validateFrom:fn writablePath:self.path];

    fbt_void_nserror_ref userCallback = [block copy];
    id<FNode> newNode = [FSnapshotUtilities nodeFrom:value priority:priority withValidationFrom:fn];

    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo set:self.path withNode:newNode withCallback:userCallback];
    });
}


- (void) removeValue {
    [self setValueInternal:nil andPriority:nil withCompletionBlock:nil from:@"removeValue:"];
}

- (void) removeValueWithCompletionBlock:(fbt_void_nserror_ref)block {
    [self setValueInternal:nil andPriority:nil withCompletionBlock:block from:@"removeValueWithCompletionBlock:"];
}


- (void) setPriority:(id)priority {
    [self setPriorityInternal:priority withCompletionBlock:nil from:@"setPriority:"];
}

- (void) setPriority:(id)priority withCompletionBlock:(fbt_void_nserror_ref)block {

    [self setPriorityInternal:priority withCompletionBlock:block from:@"setPriority:withCompletionBlock:"];
}

- (void) setPriorityInternal:(id)priority withCompletionBlock:(fbt_void_nserror_ref)block from:(NSString*)fn {
    [FValidation validateFrom:fn writablePath:self.path];

    fbt_void_nserror_ref userCallback = [block copy];
    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo set:[self.path childFromString:@".priority"] withNode:[FSnapshotUtilities nodeFrom:priority] withCallback:userCallback];
    });
}


- (void) updateChildValues:(NSDictionary *)values {
    [self updateChildValuesInternal:values withCompletionBlock:nil from:@"updateChildValues:"];
}

- (void) updateChildValues:(NSDictionary *)values withCompletionBlock:(fbt_void_nserror_ref)block {
    [self updateChildValuesInternal:values withCompletionBlock:block from:@"updateChildValues:withCompletionBlock:"];
}

- (void) updateChildValuesInternal:(NSDictionary *)values withCompletionBlock:(fbt_void_nserror_ref)block from:(NSString*)fn {
    [FValidation validateFrom:fn writablePath:self.path];

    FCompoundWrite *merge = [FSnapshotUtilities compoundWriteFromDictionary:values withValidationFrom:fn];

    fbt_void_nserror_ref userCallback = [block copy];
    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo update:self.path withNodes:merge withCallback:userCallback];
    });
}

#pragma mark -
#pragma mark Disconnect Operations

- (void) onDisconnectSetValue:(id)value {
    [self onDisconnectSetValueInternal:value andPriority:nil withCompletionBlock:nil from:@"onDisconnectSetValue:"];
}

- (void) onDisconnectSetValue:(id)value withCompletionBlock:(fbt_void_nserror_ref)block {
    [self onDisconnectSetValueInternal:value andPriority:nil withCompletionBlock:block from:@"onDisconnectSetValue:withCompletionBlock:"];
}

- (void) onDisconnectSetValue:(id)value andPriority:(id)priority {
    [self onDisconnectSetValueInternal:value andPriority:priority withCompletionBlock:nil from:@"onDisconnectSetValue:andPriority:"];
}

- (void) onDisconnectSetValue:(id)value andPriority:(id)priority withCompletionBlock:(fbt_void_nserror_ref)block {
    [self onDisconnectSetValueInternal:value andPriority:priority withCompletionBlock:block from:@"onDisconnectSetValue:andPriority:withCompletionBlock:"];
}

- (void) onDisconnectSetValueInternal:(id)value andPriority:(id)priority withCompletionBlock:(fbt_void_nserror_ref)block from:(NSString*)fn {
    [FValidation validateFrom:fn writablePath:self.path];

    id<FNode> newNodeUnresolved = [FSnapshotUtilities nodeFrom:value priority:priority withValidationFrom:fn];

    fbt_void_nserror_ref userCallback = [block copy];
    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo onDisconnectSet:self.path withNode:newNodeUnresolved withCallback:userCallback];
    });
}


- (void) onDisconnectRemoveValue {
    [self onDisconnectSetValueInternal:nil andPriority:nil withCompletionBlock:nil from:@"onDisconnectRemoveValue:"];
}

- (void) onDisconnectRemoveValueWithCompletionBlock:(fbt_void_nserror_ref)block {
    [self onDisconnectSetValueInternal:nil andPriority:nil withCompletionBlock:block from:@"onDisconnectRemoveValueWithCompletionBlock:"];
}


- (void) onDisconnectUpdateChildValues:(NSDictionary *)values {
    [self onDisconnectUpdateChildValuesInternal:values withCompletionBlock:nil from:@"onDisconnectUpdateChildValues:"];
}

- (void) onDisconnectUpdateChildValues:(NSDictionary *)values withCompletionBlock:(fbt_void_nserror_ref)block {
    [self onDisconnectUpdateChildValuesInternal:values withCompletionBlock:block from:@"onDisconnectUpdateChildValues:withCompletionBlock:"];
}

- (void) onDisconnectUpdateChildValuesInternal:(NSDictionary *)values withCompletionBlock:(fbt_void_nserror_ref)block from:(NSString*)fn {
    [FValidation validateFrom:fn writablePath:self.path];

    FCompoundWrite *merge = [FSnapshotUtilities compoundWriteFromDictionary:values withValidationFrom:fn];

    fbt_void_nserror_ref userCallback = [block copy];
    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo onDisconnectUpdate:self.path withNodes:merge withCallback:userCallback];
    });
}


- (void) cancelDisconnectOperations {
    [self cancelDisconnectOperationsWithCompletionBlock:nil];
}

- (void) cancelDisconnectOperationsWithCompletionBlock:(fbt_void_nserror_ref)block {
    fbt_void_nserror_ref callback = nil;
    if (block != nil) {
        callback = [block copy];
    }
    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo onDisconnectCancel:self.path withCallback:callback];
    });
}

#pragma mark -
#pragma mark Connection management methods

+ (void) goOffline {
    [FRepoManager interruptAll];
}

+ (void) goOnline {
    [FRepoManager resumeAll];
}


#pragma mark -
#pragma mark Data reading methods deferred to FQuery

- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType withBlock:(fbt_void_datasnapshot)block {
    return [self observeEventType:eventType withBlock:block withCancelBlock:nil];
}

- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(fbt_void_datasnapshot_nsstring)block {
    return [self observeEventType:eventType andPreviousSiblingKeyWithBlock:block withCancelBlock:nil];
}

- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType withBlock:(fbt_void_datasnapshot)block withCancelBlock:(fbt_void_nserror)cancelBlock {
    return [super observeEventType:eventType withBlock:block withCancelBlock:cancelBlock];
}

- (FIRDatabaseHandle)observeEventType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(fbt_void_datasnapshot_nsstring)block withCancelBlock:(fbt_void_nserror)cancelBlock {
    return [super observeEventType:eventType andPreviousSiblingKeyWithBlock:block withCancelBlock:cancelBlock];
}


- (void) removeObserverWithHandle:(FIRDatabaseHandle)handle {
    [super removeObserverWithHandle:handle];
}


- (void) removeAllObservers {
    [super removeAllObservers];
}

- (void) keepSynced:(BOOL)keepSynced {
    [super keepSynced:keepSynced];
}

- (void)observeSingleEventOfType:(FIRDataEventType)eventType withBlock:(fbt_void_datasnapshot)block {
    [self observeSingleEventOfType:eventType withBlock:block withCancelBlock:nil];
}

- (void)observeSingleEventOfType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(fbt_void_datasnapshot_nsstring)block {
    [self observeSingleEventOfType:eventType andPreviousSiblingKeyWithBlock:block withCancelBlock:nil];
}

- (void)observeSingleEventOfType:(FIRDataEventType)eventType withBlock:(fbt_void_datasnapshot)block withCancelBlock:(fbt_void_nserror)cancelBlock {
    [super observeSingleEventOfType:eventType withBlock:block withCancelBlock:cancelBlock];
}

- (void)observeSingleEventOfType:(FIRDataEventType)eventType andPreviousSiblingKeyWithBlock:(fbt_void_datasnapshot_nsstring)block withCancelBlock:(fbt_void_nserror)cancelBlock {
    [super observeSingleEventOfType:eventType andPreviousSiblingKeyWithBlock:block withCancelBlock:cancelBlock];
}

#pragma mark -
#pragma mark Query methods
// These methods suppress warnings from having method definitions in FIRDatabaseReference.h for docs generation.

- (FIRDatabaseQuery *)queryLimitedToFirst:(NSUInteger)limit {
    return [super queryLimitedToFirst:limit];
}

- (FIRDatabaseQuery *)queryLimitedToLast:(NSUInteger)limit {
    return [super queryLimitedToLast:limit];
}

- (FIRDatabaseQuery *)queryOrderedByChild:(NSString *)key {
    return [super queryOrderedByChild:key];
}

- (FIRDatabaseQuery *) queryOrderedByKey {
    return [super queryOrderedByKey];
}

- (FIRDatabaseQuery *) queryOrderedByPriority {
    return [super queryOrderedByPriority];
}

- (FIRDatabaseQuery *)queryStartingAtValue:(id)startValue {
    return [super queryStartingAtValue:startValue];
}

- (FIRDatabaseQuery *)queryStartingAtValue:(id)startValue childKey:(NSString *)childKey {
    return [super queryStartingAtValue:startValue childKey:childKey];
}

- (FIRDatabaseQuery *)queryEndingAtValue:(id)endValue {
    return [super queryEndingAtValue:endValue];
}

- (FIRDatabaseQuery *)queryEndingAtValue:(id)endValue childKey:(NSString *)childKey {
    return [super queryEndingAtValue:endValue childKey:childKey];
}

- (FIRDatabaseQuery *)queryEqualToValue:(id)value {
    return [super queryEqualToValue:value];
}

- (FIRDatabaseQuery *)queryEqualToValue:(id)value childKey:(NSString *)childKey {
    return [super queryEqualToValue:value childKey:childKey];
}


#pragma mark -
#pragma mark Transaction methods

- (void) runTransactionBlock:(fbt_transactionresult_mutabledata)block {
    [FValidation validateFrom:@"runTransactionBlock:" writablePath:self.path];
    [self runTransactionBlock:block andCompletionBlock:nil withLocalEvents:YES];
}

- (void) runTransactionBlock:(fbt_transactionresult_mutabledata)update andCompletionBlock:(fbt_void_nserror_bool_datasnapshot)completionBlock {
    [FValidation validateFrom:@"runTransactionBlock:andCompletionBlock:" writablePath:self.path];
    [self runTransactionBlock:update andCompletionBlock:completionBlock withLocalEvents:YES];
}

- (void) runTransactionBlock:(fbt_transactionresult_mutabledata)block andCompletionBlock:(fbt_void_nserror_bool_datasnapshot)completionBlock withLocalEvents:(BOOL)localEvents {
    [FValidation validateFrom:@"runTransactionBlock:andCompletionBlock:withLocalEvents:" writablePath:self.path];
    fbt_transactionresult_mutabledata updateCopy = [block copy];
    fbt_void_nserror_bool_datasnapshot onCompleteCopy = [completionBlock copy];
    dispatch_async([FIRDatabaseQuery sharedQueue], ^{
        [self.repo startTransactionOnPath:self.path update:updateCopy onComplete:onCompleteCopy withLocalEvents:localEvents];
    });
}

@end
