//
// Swiftfin is subject to the terms of the Mozilla Public
// License, v2.0. If a copy of the MPL was not distributed with this
// file, you can obtain one at https://mozilla.org/MPL/2.0/.
//
// Copyright (c) 2022 Jellyfin & Jellyfin Contributors
//

import ActivityIndicator
import Combine
import Foundation
import JellyfinAPI

class ViewModel: ObservableObject {

	@Published
	var isLoading = false
	@Published
	var errorMessage: ErrorMessage?

	let loading = ActivityIndicator()
	var cancellables = Set<AnyCancellable>()

	init() {
		loading.loading.assign(to: \.isLoading, on: self).store(in: &cancellables)
	}

	func handleAPIRequestError(displayMessage: String? = nil, logLevel: LogLevel = .error, tag: String = "", function: String = #function,
	                           file: String = #file, line: UInt = #line, completion: Subscribers.Completion<Error>)
	{
		switch completion {
		case .finished:
			self.errorMessage = nil
		case let .failure(error):
			let logConstructor = LogConstructor(message: "__NOTHING__", tag: tag, level: logLevel, function: function, file: file,
			                                    line: line)

			switch error {
			case is ErrorResponse:
				let networkError: NetworkError
				let errorResponse = error as! ErrorResponse
				switch errorResponse {
				case .error(-1, _, _, _):
					networkError = .URLError(response: errorResponse, displayMessage: displayMessage, logConstructor: logConstructor)
					// Use the errorResponse description for debugging, rather than the user-facing friendly description which may not be implemented
					LogManager.shared.log
						.error("Request failed: URL request failed with error \(networkError.errorMessage.code): \(errorResponse.localizedDescription)")
				case .error(-2, _, _, _):
					networkError = .HTTPURLError(response: errorResponse, displayMessage: displayMessage, logConstructor: logConstructor)
					LogManager.shared.log
						.error("Request failed: HTTP URL request failed with description: \(errorResponse.localizedDescription)")
				default:
					networkError = .JellyfinError(response: errorResponse, displayMessage: displayMessage, logConstructor: logConstructor)
					// Able to use user-facing friendly description here since just HTTP status codes
					LogManager.shared.log
						.error("Request failed: \(networkError.errorMessage.code) - \(networkError.errorMessage.title): \(networkError.errorMessage.logConstructor.message)\n\(error.localizedDescription)")
				}

				self.errorMessage = networkError.errorMessage

				networkError.logMessage()

			case is SwiftfinStore.Errors:
				let swiftfinError = error as! SwiftfinStore.Errors
				let errorMessage = ErrorMessage(code: ErrorMessage.noShowErrorCode,
				                                title: swiftfinError.title,
				                                displayMessage: swiftfinError.errorDescription ?? "",
				                                logConstructor: logConstructor)
				self.errorMessage = errorMessage
				LogManager.shared.log.error("Request failed: \(swiftfinError.errorDescription ?? "")")

			default:
				let genericErrorMessage = ErrorMessage(code: ErrorMessage.noShowErrorCode,
				                                       title: "Generic Error",
				                                       displayMessage: error.localizedDescription,
				                                       logConstructor: logConstructor)
				self.errorMessage = genericErrorMessage
				LogManager.shared.log.error("Request failed: Generic error - \(error.localizedDescription)")
			}
		}
	}
}