import 'dart:convert';

import 'package:flutter/widgets.dart';
import 'package:flutter_secure_storage/flutter_secure_storage.dart';
import 'package:http/http.dart';
import 'package:seshat/config/constants.dart';
import 'package:seshat/domain/models/bal.dart';
import 'package:seshat/domain/models/book.dart';
import 'package:seshat/domain/models/book_instance.dart';
import 'package:seshat/domain/models/owner.dart';
import 'package:seshat/domain/models/search_result.dart';
import 'package:seshat/utils/command.dart';
import 'package:seshat/utils/result.dart';

typedef AuthHeaderProvider = String? Function();

class ApiClient {
  ApiClient({String? host, int? port});

  late final Command0 load;
  String? token;
  bool isReady = false;
  FlutterSecureStorage? _secureStorage;

  Future<void> _initStore() async {
    _secureStorage ??= const FlutterSecureStorage(
      aOptions: AndroidOptions(encryptedSharedPreferences: true),
    );
  }

  Future<Map<String, String>> _getHeaders([
    Map<String, String>? additionalHeaders,
  ]) async {
    await _initStore();
    final token = await _secureStorage!.read(key: "token");
    final headers = {"Authorization": "Bearer $token", ...?additionalHeaders};
    return headers;
  }

  /*
 * =================
 * =====[ BAL ]=====
 * =================
*/

  Future<Result<Bal>> stopBal(int id) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.post(
        Uri.parse("https://$apiBasePath/bal/${id.toString()}/stop"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Bal.fromJSON(json));
      } else if (response.statusCode == 403) {
        throw "You don't own the specified BAL";
      } else if (response.statusCode == 404) {
        throw "No BAL with specified ID found";
      } else if (response.statusCode == 409) {
        throw "Selected BAL was not on ongoing state";
      } else {
        throw "Unknown error";
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<Bal>> startBal(int id) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.post(
        Uri.parse("https://$apiBasePath/bal/${id.toString()}/start"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Bal.fromJSON(json));
      } else if (response.statusCode == 403) {
        throw "You don't own the specified BAL";
      } else if (response.statusCode == 404) {
        throw "No BAL with specified ID found";
      } else if (response.statusCode == 409) {
        throw "Cannot have multiple BAl ongoing at the same time!";
      } else {
        throw "Unknown error";
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<Bal>> editBal(
    int id,
    String name,
    DateTime start,
    DateTime end,
  ) async {
    final client = Client();
    try {
      final headers = await _getHeaders({"Content-Type": "application/json"});
      final body = {
        "name": name,
        "start_timestamp": (start.millisecondsSinceEpoch / 1000).round(),
        "end_timestamp": (end.millisecondsSinceEpoch / 1000).round(),
      };
      final response = await client.patch(
        Uri.parse("https://$apiBasePath/bal/${id.toString()}"),
        headers: headers,
        body: jsonEncode(body),
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Bal.fromJSON(json));
      } else {
        throw Exception("Something went wrong");
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<Bal>> getBalById(int id) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/bal/${id.toString()}"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Bal.fromJSON(json));
      } else if (response.statusCode == 403) {
        throw Exception("You don't own the specified bal");
      } else {
        return Result.error(
          Exception("No bal wirth this id exists the database"),
        );
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<Bal>> addBal(String name, DateTime start, DateTime end) async {
    final client = Client();
    try {
      final headers = await _getHeaders({"Content-Type": "application/json"});
      final body = {
        "name": name,
        "start_timestamp": (start.millisecondsSinceEpoch / 1000).round(),
        "end_timestamp": (end.millisecondsSinceEpoch / 1000).round(),
      };
      final response = await client.post(
        Uri.parse("https://$apiBasePath/bal"),
        headers: headers,
        body: jsonEncode(body),
      );
      if (response.statusCode == 201) {
        final json = jsonDecode(response.body);
        return Result.ok(Bal.fromJSON(json));
      } else {
        throw Exception("Something went wrong");
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<List<Bal>>> getBals() async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/bals"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body) as List<dynamic>;
        debugPrint("\n\n\n\nRECEIVED : $json\n\n\n\n");
        debugPrint(
          "\n\n\n\nFORMATTED : ${json.map((element) => Bal.fromJSON(element)).toList()}\n\n\n\n",
        );

        return Result.ok(json.map((element) => Bal.fromJSON(element)).toList());
      } else {
        throw Exception("Something wrong happened");
      }
    } catch (e) {
      debugPrint("ERROR: ${e.toString()}");
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<Bal?>> getCurrentBal() async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/bal/current"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Bal.fromJSON(json));
      } else if (response.statusCode == 404) {
        return Result.ok(null);
      } else {
        throw Exception("Something went wrong");
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  /*
 * ===================
 * =====[ BOOKS ]=====
 * ===================
*/

  Future<Result<Book>> getBookById(int id) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/book/id/${id.toString()}"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Book.fromJSON(json));
      } else {
        throw Exception("The book was not found");
      }
    } catch (e) {
      return Result.error(Exception("API $e"));
    } finally {
      client.close();
    }
  }

  Future<Result<Book>> getBookByEAN(String ean) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/book/ean/$ean"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Book.fromJSON(json));
      } else {
        throw Exception("The book was not found");
      }
    } catch (e) {
      return Result.error(Exception("API $e"));
    } finally {
      client.close();
    }
  }

  /*
 * =============================
 * =====[ BOOKS INSTANCES ]=====
 * =============================
*/

  Future<Result<List<SearchResult>>> getBookInstanceBySearch(
    int balId,
    String title,
    String author,
  ) async {
    final client = Client();
    try {
      final headers = await _getHeaders({"Content-Type": "application/json"});
      final body = jsonEncode({"title": title, "author": author});
      debugPrint("\n\n\n\n$body\n\n\n\n");
      final response = await client.post(
        Uri.parse("https://$apiBasePath/bal/${balId.toString()}/search"),
        headers: headers,
        body: body,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body) as List<dynamic>;
        debugPrint("\n\n\n\nJSON : $json\n\n\n\n");
        return Result.ok(json.map((el) => SearchResult.fromJSON(el)).toList());
      } else {
        throw "Unknown Error";
      }
    } catch (e) {
      debugPrint("\n\n\n\nERROR: ${e.toString()}\n\n\n\n");
      return Result.error(Exception("API $e"));
    } finally {
      client.close();
    }
  }

  Future<Result<List<BookInstance>>> getBookInstanceByEAN(
    int balId,
    int ean,
  ) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse(
          "https://$apiBasePath/bal/${balId.toString()}/ean/${ean.toString()}/book_instances",
        ),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body) as List<dynamic>;
        return Result.ok(json.map((el) => BookInstance.fromJSON(el)).toList());
      } else {
        throw "Unknown Error";
      }
    } catch (e) {
      return Result.error(Exception("API $e"));
    } finally {
      client.close();
    }
  }

  Future<Result<void>> sellBooks(Map<String, double?> books) async {
    final client = Client();
    try {
      final headers = await _getHeaders({"Content-Type": "application/json"});
      debugPrint("\n\n\n\nMAP: $books\n\n\n\n");
      final body = jsonEncode(books);
      debugPrint("\n\n\n\nSENT: $body\n\n\n\n");
      final response = await client.post(
        Uri.parse("https://$apiBasePath/book_instance/sell/bulk"),
        headers: headers,
        body: body,
      );
      if (response.statusCode == 200) {
        return Result.ok(response.statusCode);
      } else {
        throw "Unknown error";
      }
    } catch (e) {
      debugPrint("\n\n\n\nERROR : ${e.toString()}\n\n\n\n");
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  Future<Result<BookInstance>> sendBook(
    Book book,
    Owner owner,
    Bal bal,
    double price,
  ) async {
    final client = Client();
    try {
      final headers = await _getHeaders({"Content-Type": "application/json"});
      final body = jsonEncode({
        "bal_id": bal.id,
        "book_id": book.id,
        "owner_id": owner.id,
        "price": price,
      });
      final response = await client.post(
        Uri.parse("https://$apiBasePath/book_instance"),
        headers: headers,
        body: body,
      );
      if (response.statusCode == 201) {
        final json = jsonDecode(response.body);
        return Result.ok(BookInstance.fromJSON(json));
      } else if (response.statusCode == 403) {
        throw Exception("You don't own that book instance");
      } else {
        throw Exception("Something wrong happened");
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  /*
 * ====================
 * =====[ OWNERS ]=====
 * ====================
*/

  Future<Result<Owner>> getOwnerById(int id) async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/owner/${id.toString()}"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Owner.fromJSON(json));
      } else {
        throw Exception("The owner was not found");
      }
    } catch (e) {
      return Result.error(Exception("API $e"));
    } finally {
      client.close();
    }
  }

  Future<Result<Owner>> getSectionOwner() async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/owner/self"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body);
        return Result.ok(Owner.fromJSON(json));
      } else {
        throw "Unknown error";
      }
    } catch (e) {
      return Result.error(Exception(e));
    } finally {
      client.close();
    }
  }

  /// Call on `/owners` to get a list of all [Owner]s
  Future<Result<List<Owner>>> getOwners() async {
    final client = Client();
    try {
      final headers = await _getHeaders();
      final response = await client.get(
        Uri.parse("https://$apiBasePath/owners"),
        headers: headers,
      );
      if (response.statusCode == 200) {
        final json = jsonDecode(response.body) as List<dynamic>;
        return Result.ok(
          json.map((element) => Owner.fromJSON(element)).toList(),
        );
      } else {
        throw Exception("Invalid request");
      }
    } on Exception catch (error) {
      return Result.error(error);
    } finally {
      client.close();
    }
  }

  /// Adds an owner to the database
  Future<Result<Owner>> addOwner(
    String firstName,
    String lastName,
    String contact,
  ) async {
    final client = Client();
    try {
      final headers = await _getHeaders({"Content-Type": "application/json"});
      final body = {
        "first_name": firstName,
        "last_name": lastName,
        "contact": contact,
      };
      final response = await client.post(
        Uri.parse("https://$apiBasePath/owner"),
        headers: headers,
        body: jsonEncode(body),
      );
      if (response.statusCode == 201) {
        final json = jsonDecode(response.body);
        return Result.ok(Owner.fromJSON(json));
      } else {
        throw Exception("Invalid request");
      }
    } on Exception catch (error) {
      return Result.error(error);
    } finally {
      client.close();
    }
  }
}