import { Injectable, NotFoundException } from '@nestjs/common';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { Task } from './task.entity';
import { ProjectsService } from '../projects/projects.service';

@Injectable()
export class TasksService {
  constructor(
    @InjectRepository(Task)
    private tasksRepository: Repository<Task>,
    private projectsService: ProjectsService,
  ) {}

  async create(data: { title: string; projectId: number; assignedUserId?: number; deadline?: Date }) {
    const project = await this.projectsService.findOneById(data.projectId);
    if (!project) throw new NotFoundException('Project not found');

    const task = this.tasksRepository.create({
      title: data.title,
      project,
      assignedUserId: data.assignedUserId,
      deadline: data.deadline,
    });

    return this.tasksRepository.save(task);
  }

  async findAll(): Promise<Task[]> {
    return this.tasksRepository.find();
  }

  async findOneById(id: number): Promise<Task | null> {
    return this.tasksRepository.findOne({ where: { id } });
  }

  async findByProjectId(projectId: number): Promise<Task[]> {
    return this.tasksRepository.find({
      where: { project: { id: projectId } },
    });
  }

  async update(id: number, data: { title?: string; status?: string; deadline?: Date; assignedUserId?: number }) {
    const task = await this.findOneById(id);
    if (!task) throw new NotFoundException('Task not found');

    if (data.title !== undefined) task.title = data.title;
    if (data.status !== undefined) task.status = data.status;
    if (data.deadline !== undefined) task.deadline = data.deadline;
    if (data.assignedUserId !== undefined) {
      task.assignedUserId = data.assignedUserId; 
    }

    return this.tasksRepository.save(task);
  }

  async delete(id: number) {
    const result = await this.tasksRepository.delete(id);
    if (result.affected === 0) {
      throw new NotFoundException('Task not found');
    }
  }
}