import 'dart:async';
import 'package:path/path.dart';
import 'package:sqflite/sqflite.dart';
import '../models/dog.dart';

class DatabaseClient {
  Database _db;

  Future open() async {
    try {
      String dbPath = join(await getDatabasesPath(), 'database.db');
      _db = await openDatabase(dbPath, version: 1, onCreate: this._create);
    }
    catch (error) {
      throw Exception('Falha ao abrir o BD!');
    }
  }

  Future _create(Database db, int version) async {
    try {
      await db.execute("""
            CREATE TABLE dogs (
              id TEXT PRIMARY KEY, 
              name TEXT, 
              age INTEGER
            )""");
    }
    catch (error) {
      throw Exception('Falha ao criar tabela no BD!');
    }
  }

  Future insertDogs(List<Dog> dogs) async {
    try {
      await Future.forEach(dogs, (dog) async {
        await _db.insert('dogs', dog.toMap(),
            conflictAlgorithm: ConflictAlgorithm.replace);
      });
    }
    catch (error) {
      throw Exception('Falha ao inserir lista de dados no BD!');
    }
  }

  Future insertDog(Dog dog) async {
    try {
      await _db.insert('dogs', dog.toMap(),
          conflictAlgorithm: ConflictAlgorithm.replace);
    }
    catch (error) {
      throw Exception('Falha ao inserir dado no BD!');
    }
  }

  Future<Dog> getDog(String id) async {
    try {
      final List<Map<String, dynamic>> maps =
          await _db.query('dogs', where: "id = ?", whereArgs: [id], limit: 1);

      if (maps.length > 0) {
        return Dog.fromMap(maps[0]);
      }
      else {
        return null;
      }
    }
    catch (error) {
      throw Exception('Falha ao obter dado no BD!');
    }
  }

  Future<List<Dog>> getDogs() async {
    try {
      final List<Map<String, dynamic>> maps = await _db.query('dogs');
      return List.generate(maps.length, (i) {
        return Dog.fromMap(maps[i]);
      });
    }
    catch (error) {
      throw Exception('Falha ao obter lista de dados no BD!');
    }
  }

  Future updateDog(Dog dog) async {
    try {
      _db.update(
        'dogs',
        dog.toMap(),
        where: "id = ?",
        whereArgs: [dog.id],
      );
    }
    catch (error) {
      throw Exception('Falha ao atualizar dado no BD!');
    }
  }

  Future deleteDog(String id) async {
    try {
      await _db.delete('dogs', where: "id = ?", whereArgs: [id]);
    }
    catch (error) {
      throw Exception('Falha ao deletar dado no BD!');
    }
  }

  Future deleteAllDogs() async {
    try {
      await _db.execute("""DELETE FROM dogs""");
    }
    catch (error) {
      throw Exception('Falha ao deletar todos os dados do BD!');
    }
  }
}