//
// Copyright Amazon.com Inc. or its affiliates.
// All Rights Reserved.
//
// SPDX-License-Identifier: Apache-2.0
//

import Amplify
import Combine

class MockDataStoreCategoryPlugin: MessageReporter, DataStoreCategoryPlugin {

    var responders = [ResponderKeys: Any]()

    var key: String {
        return "MockDataStoreCategoryPlugin"
    }

    func configure(using configuration: Any?) throws {
        notify()
    }

    func reset() {
        notify("reset")
    }

    func save<M: Model>(_ model: M,
                        where condition: QueryPredicate? = nil,
                        completion: (DataStoreResult<M>) -> Void) {
        notify("save")

        if let responder = responders[.saveModelListener] as? SaveModelResponder<M> {
            if let callback = responder.callback((model: model,
                                                  where: condition)) {
                completion(callback)
            }
        }
    }
    
    func save<M: Model>(_ model: M,
                        where condition: QueryPredicate? = nil) async throws -> M {
        notify("save")
        return model
    }

    func query<M: Model>(_ modelType: M.Type,
                         byId id: String,
                         completion: (DataStoreResult<M?>) -> Void) {
        notify("queryById")

        if let responder = responders[.queryByIdListener] as? QueryByIdResponder<M> {
            if let callback = responder.callback((modelType: modelType, id: id)) {
                completion(callback)
            }
        }
    }
    
    func query<M: Model>(_ modelType: M.Type,
                         byId id: String) async throws -> M? {
        notify("queryById")
        return nil
    }

    func query<M: Model>(_ modelType: M.Type,
                         byIdentifier id: String,
                         completion: (DataStoreResult<M?>) -> Void) where M: ModelIdentifiable,
                                                                          M.IdentifierFormat == ModelIdentifierFormat.Default {
        notify("queryByIdentifier")

        if let responder = responders[.queryByIdListener] as? QueryByIdResponder<M> {
            if let callback = responder.callback((modelType: modelType, id: id)) {
                completion(callback)
            }
        }
    }
    
    func query<M: Model>(_ modelType: M.Type,
                         byIdentifier id: String) async throws -> M? where M: ModelIdentifiable,
        M.IdentifierFormat == ModelIdentifierFormat.Default {
            notify("queryByIdentifier")
            return nil
    }

    func query<M: Model>(_ modelType: M.Type,
                         where predicate: QueryPredicate?,
                         sort sortInput: QuerySortInput?,
                         paginate paginationInput: QueryPaginationInput?,
                         completion: (DataStoreResult<[M]>) -> Void) {
        notify("queryByPredicate")

        if let responder = responders[.queryModelsListener] as? QueryModelsResponder<M> {
            if let result = responder.callback((modelType: modelType,
                                                  where: predicate,
                                                  sort: sortInput,
                                                  paginate: paginationInput)) {
                completion(result)
            }
        }
    }
    
    func query<M: Model>(_ modelType: M.Type,
                         where predicate: QueryPredicate?,
                         sort sortInput: QuerySortInput?,
                         paginate paginationInput: QueryPaginationInput?) async throws -> [M] {
        notify("queryByPredicate")
        
        if let responder = responders[.queryModelsListener] as? QueryModelsResponder<M> {
            if let result = responder.callback((modelType: modelType,
                                                  where: predicate,
                                                  sort: sortInput,
                                                  paginate: paginationInput)) {
                switch result {
                case .success(let models):
                    return models
                case .failure(let error):
                    throw error
                }
            }
        }
        
        return []
    }

    func query<M>(_ modelType: M.Type,
                  byIdentifier id: ModelIdentifier<M, M.IdentifierFormat>,
                  completion: (DataStoreResult<M?>) -> Void) where M: Model, M: ModelIdentifiable {
        notify("queryWithIdentifier")

       if let responder = responders[.queryByIdListener] as? QueryByIdResponder<M> {
           if let callback = responder.callback((modelType: modelType, id: id.stringValue)) {
               completion(callback)
           }
       }
    }
    
    func query<M>(_ modelType: M.Type,
                  byIdentifier id: ModelIdentifier<M, M.IdentifierFormat>) async throws -> M?
        where M: Model, M: ModelIdentifiable {
            notify("queryWithIdentifier")
            return nil
    }

    func delete<M: Model>(_ modelType: M.Type,
                          withId id: String,
                          where predicate: QueryPredicate? = nil,
                          completion: (DataStoreResult<Void>) -> Void) {
        notify("deleteById")

        if let responder = responders[.deleteByIdListener] as? DeleteByIdResponder<M> {
            if let callback = responder.callback((modelType: modelType, id: id)) {
                completion(callback)
            }
        }
    }
    
    func delete<M: Model>(_ modelType: M.Type,
                          withId id: String,
                          where predicate: QueryPredicate? = nil) async throws {
        notify("deleteById")
    }

    func delete<M: Model>(_ modelType: M.Type,
                          withIdentifier id: String,
                          where predicate: QueryPredicate? = nil,
                          completion: @escaping (DataStoreResult<Void>) -> Void) where M: ModelIdentifiable,
                                                                             M.IdentifierFormat == ModelIdentifierFormat.Default {
        notify("deleteByIdentifier")

        if let responder = responders[.deleteByIdListener] as? DeleteByIdResponder<M> {
            if let callback = responder.callback((modelType: modelType, id: id)) {
                completion(callback)
            }
        }
    }

    func delete<M: Model>(_ modelType: M.Type,
                          withIdentifier id: String,
                          where predicate: QueryPredicate? = nil) async throws
        where M: ModelIdentifiable, M.IdentifierFormat == ModelIdentifierFormat.Default {
            notify("deleteByIdentifier")
    }
    
    func delete<M>(_ modelType: M.Type,
                   withIdentifier id: ModelIdentifier<M, M.IdentifierFormat>,
                   where predicate: QueryPredicate?,
                   completion: @escaping DataStoreCallback<Void>) where M: Model, M: ModelIdentifiable {
        notify("deleteByIdentifier")

        if let responder = responders[.deleteByIdListener] as? DeleteByIdResponder<M> {
            if let callback = responder.callback((modelType: modelType, id: id.stringValue)) {
                completion(callback)
            }
        }
    }

    func delete<M>(_ modelType: M.Type,
                   withIdentifier id: ModelIdentifier<M, M.IdentifierFormat>,
                   where predicate: QueryPredicate?) async throws where M: Model, M: ModelIdentifiable {
        notify("deleteByIdentifier")
    }
    
    func delete<M: Model>(_ modelType: M.Type,
                           where predicate: QueryPredicate,
                           completion: (DataStoreResult<Void>) -> Void) {
        notify("deleteModelTypeByPredicate")

        if let responder = responders[.deleteModelTypeListener] as? DeleteModelTypeResponder<M> {
            if let callback = responder.callback((modelType: modelType, where: predicate)) {
                completion(callback)
            }
        }
    }
    
    func delete<M: Model>(_ modelType: M.Type,
                           where predicate: QueryPredicate) async throws {
        notify("deleteModelTypeByPredicate")
    }

    func delete<M: Model>(_ model: M,
                          where predicate: QueryPredicate? = nil,
                          completion: @escaping DataStoreCallback<Void>) {
        notify("deleteByPredicate")

        if let responder = responders[.deleteModelListener] as? DeleteModelResponder<M> {
            if let callback = responder.callback((model: model,
                                                  where: predicate)) {
                completion(callback)
            }
        }
    }
    
    func delete<M: Model>(_ model: M,
                          where predicate: QueryPredicate? = nil) async throws {
        notify("deleteByPredicate")
    }

    func clear(completion: @escaping DataStoreCallback<Void>) {
        notify("clear")

        if let responder = responders[.clearListener] as? ClearResponder {
            if let callback = responder.callback(()) {
                completion(callback)
            }
        }
    }
    
    func clear() async throws {
        notify("clear")
    }

    func start(completion: @escaping DataStoreCallback<Void>) {
        notify("start")

        if let responder = responders[.clearListener] as? ClearResponder {
            if let callback = responder.callback(()) {
                completion(callback)
            }
        }
    }
    
    func start() async throws {
        notify("start")
    }

    func stop(completion: @escaping DataStoreCallback<Void>) {
        notify("stop")

        if let responder = responders[.stopListener] as? StopResponder {
            if let callback = responder.callback(()) {
                completion(callback)
            }
        }
    }

    func stop() async throws {
        notify("stop")
    }
    
    func publisher<M: Model>(for modelType: M.Type)
    -> AnyPublisher<MutationEvent, DataStoreError> {
        let mutationEvent = MutationEvent(id: "testevent",
                                          modelId: "123",
                                          modelName: modelType.modelName,
                                          json: "",
                                          mutationType: .create,
                                          createdAt: .now())
        notify("publisher")
        return Result.Publisher(mutationEvent).eraseToAnyPublisher()
    }

    func observe<M: Model>(_ modelType: M.Type) -> AmplifyAsyncThrowingSequence<MutationEvent> {
        return AmplifyAsyncThrowingSequence(parent: nil)
    }
    
    public func observeQuery<M: Model>(for modelType: M.Type,
                                       where predicate: QueryPredicate? = nil,
                                       sort sortInput: QuerySortInput? = nil)
    -> AnyPublisher<DataStoreQuerySnapshot<M>, DataStoreError> {
        notify("observeQuery")
        let snapshot = DataStoreQuerySnapshot<M>(items: [], isSynced: false)
        return Result.Publisher(snapshot).eraseToAnyPublisher()
    }
    
    func observeQuery<M: Model>(for modelType: M.Type,
                                where predicate: QueryPredicate?,
                                sort sortInput: QuerySortInput?) -> AmplifyAsyncThrowingSequence<DataStoreQuerySnapshot<M>> {
        
        let request = ObserveQueryRequest(options: [])
        let taskRunner = MockObserveQueryTaskRunner<M>(request: request)
        return taskRunner.sequence
    }
}

class MockSecondDataStoreCategoryPlugin: MockDataStoreCategoryPlugin {
    override var key: String {
        return "MockSecondDataStoreCategoryPlugin"
    }
}


class ObserveQueryRequest: AmplifyOperationRequest {
    var options: Any
    
    typealias Options = Any
    
    init(options: Any) {
        self.options = options
    }
    
}

class MockObserveQueryTaskRunner<M: Model>: InternalTaskRunner, InternalTaskAsyncThrowingSequence, InternalTaskThrowingChannel {

    public typealias Request = ObserveQueryRequest
    public typealias InProcess = DataStoreQuerySnapshot<M>
    public var request: ObserveQueryRequest
    public var context = InternalTaskAsyncThrowingSequenceContext<DataStoreQuerySnapshot<M>>()
    func run() async throws {

    }

    init(request: ObserveQueryRequest) {
        self.request = request
    }

}