import { HttpException, HttpStatus, Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';
import { InjectRepository } from '@nestjs/typeorm';
import { Resume as ResumeSchema } from '@reactive-resume/schema';
import { unlink } from 'fs/promises';
import { pick, sample, set } from 'lodash';
import { nanoid } from 'nanoid';
import { join } from 'path';
import { Repository } from 'typeorm';

import { PostgresErrorCode } from '@/database/errorCodes.enum';
import { UsersService } from '@/users/users.service';

import { covers } from './data/covers';
import defaultState from './data/defaultState';
import sampleData from './data/sampleData';
import { CreateResumeDto } from './dto/create-resume.dto';
import { UpdateResumeDto } from './dto/update-resume.dto';
import { Resume } from './entities/resume.entity';

export const SHORT_ID_LENGTH = 8;

@Injectable()
export class ResumeService {
  constructor(
    @InjectRepository(Resume) private resumeRepository: Repository<Resume>,
    private configService: ConfigService,
    private usersService: UsersService
  ) {}

  async create(createResumeDto: CreateResumeDto, userId: number) {
    try {
      const user = await this.usersService.findById(userId);
      const serverUrl = this.configService.get<string>('app.serverUrl');

      const shortId = nanoid(SHORT_ID_LENGTH);
      const image = `${serverUrl}/covers/${sample(covers)}`;

      const resume = this.resumeRepository.create({
        ...defaultState,
        ...createResumeDto,
        shortId,
        image,
        user,
        basics: {
          ...defaultState.basics,
          name: user.name,
        },
      });

      return await this.resumeRepository.save(resume);
    } catch (error: any) {
      if (error?.code === PostgresErrorCode.UniqueViolation) {
        throw new HttpException(
          'A resume with the same slug already exists, please enter a unique slug and try again.',
          HttpStatus.BAD_REQUEST
        );
      }

      throw new HttpException(
        'Something went wrong. Please try again later, or raise an issue on GitHub if the problem persists.',
        HttpStatus.INTERNAL_SERVER_ERROR
      );
    }
  }

  async import(importResumeDto: Partial<ResumeSchema>, userId: number) {
    try {
      const user = await this.usersService.findById(userId);
      const serverUrl = this.configService.get<string>('app.serverUrl');

      const shortId = nanoid(SHORT_ID_LENGTH);
      const image = `${serverUrl}/covers/${sample(covers)}`;

      const resume = this.resumeRepository.create({
        ...defaultState,
        ...importResumeDto,
        shortId,
        image,
        user,
      });

      return this.resumeRepository.save(resume);
    } catch {
      throw new HttpException(
        'Something went wrong. Please try again later, or raise an issue on GitHub if the problem persists.',
        HttpStatus.INTERNAL_SERVER_ERROR
      );
    }
  }

  findAll() {
    return this.resumeRepository.find();
  }

  findAllByUser(userId: number) {
    return this.resumeRepository.find({ user: { id: userId } });
  }

  async findOne(id: number, userId?: number) {
    const resume = await this.resumeRepository.findOne(id);

    if (!resume) {
      throw new HttpException('The resume you are looking does not exist, or maybe never did?', HttpStatus.NOT_FOUND);
    }

    const isPrivate = !resume.public;
    const isNotOwner = resume.user.id !== userId;

    if (isPrivate && isNotOwner) {
      throw new HttpException('The resume you are looking does not exist, or maybe never did?', HttpStatus.NOT_FOUND);
    }

    return resume;
  }

  async findOneByShortId(shortId: string, userId?: number, secretKey?: string) {
    const resume = await this.resumeRepository.findOne({ shortId });

    if (!resume) {
      throw new HttpException('The resume you are looking does not exist, or maybe never did?', HttpStatus.NOT_FOUND);
    }

    const isPrivate = !resume.public;
    const isOwner = resume.user.id === userId;
    const isInternal = secretKey === this.configService.get<string>('app.secretKey');

    if (!isInternal && isPrivate && !isOwner) {
      throw new HttpException('The resume you are looking does not exist, or maybe never did?', HttpStatus.NOT_FOUND);
    }

    return resume;
  }

  async findOneByIdentifier(username: string, slug: string, userId?: number, secretKey?: string) {
    const resume = await this.resumeRepository.findOne({ user: { username }, slug });

    if (!resume) {
      throw new HttpException('The resume you are looking does not exist, or maybe never did?', HttpStatus.NOT_FOUND);
    }

    const isPrivate = !resume.public;
    const isOwner = resume.user.id === userId;
    const isInternal = secretKey === this.configService.get<string>('app.secretKey');

    if (!isInternal && isPrivate && !isOwner) {
      throw new HttpException('The resume you are looking does not exist, or maybe never did?', HttpStatus.NOT_FOUND);
    }

    return resume;
  }

  async update(id: number, updateResumeDto: UpdateResumeDto, userId: number) {
    const resume = await this.findOne(id, userId);

    const updatedResume = {
      ...resume,
      ...updateResumeDto,
    };

    return this.resumeRepository.save<Resume>(updatedResume);
  }

  async remove(id: number, userId: number) {
    await this.resumeRepository.delete({ id, user: { id: userId } });
  }

  async duplicate(id: number, userId: number) {
    try {
      const originalResume = await this.findOne(id, userId);
      const serverUrl = this.configService.get<string>('app.serverUrl');

      const shortId = nanoid(SHORT_ID_LENGTH);
      const image = `${serverUrl}/covers/${sample(covers)}`;

      const duplicatedResume: Partial<Resume> = {
        ...pick(originalResume, ['name', 'slug', 'basics', 'metadata', 'sections', 'public']),
        name: `${originalResume.name} Copy`,
        slug: `${originalResume.slug}-copy`,
        shortId,
        image,
      };

      const resume = this.resumeRepository.create({
        ...duplicatedResume,
        user: { id: userId },
      });

      return this.resumeRepository.save(resume);
    } catch (error: any) {
      if (error?.code === PostgresErrorCode.UniqueViolation) {
        throw new HttpException(
          'A resume with the same slug already exists, please enter a unique slug and try again.',
          HttpStatus.BAD_REQUEST
        );
      }

      throw new HttpException(
        'Something went wrong. Please try again later, or raise an issue on GitHub if the problem persists.',
        HttpStatus.INTERNAL_SERVER_ERROR
      );
    }
  }

  async sample(id: number, userId: number) {
    const resume = await this.findOne(id, userId);

    const sampleResume = { ...resume, ...sampleData };

    return this.resumeRepository.save<Resume>(sampleResume);
  }

  async reset(id: number, userId: number) {
    const resume = await this.findOne(id, userId);

    const prevResume = pick(resume, ['id', 'shortId', 'name', 'slug', 'image', 'user', 'createdAt']);
    const nextResume = { ...prevResume, ...defaultState };

    return this.resumeRepository.update(id, nextResume);
  }

  async uploadPhoto(id: number, userId: number, filename: string) {
    const resume = await this.findOne(id, userId);
    const serverUrl = this.configService.get<string>('app.serverUrl');

    const url = `${serverUrl}/uploads/${userId}/${id}/${filename}`;
    const updatedResume = set(resume, 'basics.photo.url', url);

    return this.resumeRepository.save<Resume>(updatedResume);
  }

  async deletePhoto(id: number, userId: number) {
    const resume = await this.findOne(id, userId);
    const key = new URL(resume.basics.photo.url).pathname;
    const photoPath = join(__dirname, 'assets', key);
    const updatedResume = set(resume, 'basics.photo.url', '');

    await unlink(photoPath);

    return this.resumeRepository.save<Resume>(updatedResume);
  }
}