package service

import (
	"context"

	"github.com/Caknoooo/go-gin-clean-starter/database/entities"
	dtodomain "github.com/Caknoooo/go-gin-clean-starter/modules/assignment/dto"
	"github.com/Caknoooo/go-gin-clean-starter/modules/assignment/query"
	"github.com/Caknoooo/go-gin-clean-starter/modules/assignment/repository"
	pkgdto "github.com/Caknoooo/go-gin-clean-starter/pkg/dto"
	"github.com/google/uuid"
	"gorm.io/gorm"
)

type AssignmentService interface {
	Create(ctx context.Context, req dtodomain.AssignmentCreateRequest) (dtodomain.AssignmentResponse, error)
	GetById(ctx context.Context, id string) (dtodomain.AssignmentResponse, error)
	GetAll(ctx context.Context, filter query.AssignmentFilter) ([]dtodomain.AssignmentResponse, int64, error)
	Update(ctx context.Context, req dtodomain.AssignmentUpdateRequest, id string) (dtodomain.AssignmentResponse, error)
	Delete(ctx context.Context, id string) error
}

type assignmentService struct {
	db                 *gorm.DB
	assignmentRepo     repository.AssignmentRepository
	assignmentUserRepo repository.AssignmentUserRepository
}

func toAssignmentResponse(e entities.TAssignmentEntity) dtodomain.AssignmentResponse {
	client := pkgdto.IdNameResponse{}
	if e.Client.ID != uuid.Nil {
		client = pkgdto.IdNameResponse{
			ID:   e.Client.ID.String(),
			Name: e.Client.Name,
		}
	}
	users := make([]dtodomain.AssignmentUserResponse, 0)
	for _, user := range e.AssignmentUsers {
		userResp := dtodomain.AssignmentUserResponse{
			ID:       user.ID.String(),
			TaskType: user.TaskType,
			User:     pkgdto.IdNameResponse{ID: user.User.ID.String(), Name: user.User.Name},
			Role:     pkgdto.IdNameResponse{ID: user.Role.ID.String(), Name: user.Role.Name},
			Client:   pkgdto.IdNameResponse{ID: user.Client.ID.String(), Name: user.Client.Name},
		}
		users = append(users, userResp)
	}
	return dtodomain.AssignmentResponse{
		ID:              e.ID.String(),
		DocumentType:    e.DocumentType,
		DocumentID:      e.DocumentID.String(),
		Client:          client,
		AssignmentUsers: users,
	}
}

func (s *assignmentService) Create(ctx context.Context, req dtodomain.AssignmentCreateRequest) (dtodomain.AssignmentResponse, error) {
	tx := s.db.Begin()
	defer func() {
		if r := recover(); r != nil {
			tx.Rollback()
		}
	}()
	clientUUID, err := uuid.Parse(req.ClientID)
	if err != nil {
		tx.Rollback()
		return dtodomain.AssignmentResponse{}, err
	}
	documentUUID, err := uuid.Parse(req.DocumentID)
	if err != nil {
		tx.Rollback()
		return dtodomain.AssignmentResponse{}, err
	}
	assignment := entities.TAssignmentEntity{
		DocumentType: req.DocumentType,
		DocumentID:   documentUUID,
		ClientID:     clientUUID,
	}
	created, err := s.assignmentRepo.Create(ctx, tx, assignment)
	if err != nil {
		tx.Rollback()
		return dtodomain.AssignmentResponse{}, err
	}

	// Bulk create assignment users
	var assignmentUsers []entities.TAssignmentUserEntity
	for _, userReq := range req.AssignmentUsers {
		userUUID, err := uuid.Parse(userReq.UserID)
		if err != nil {
			tx.Rollback()
			return dtodomain.AssignmentResponse{}, err
		}
		roleUUID, err := uuid.Parse(userReq.RoleID)
		if err != nil {
			tx.Rollback()
			return dtodomain.AssignmentResponse{}, err
		}
		clientUUID, err := uuid.Parse(userReq.ClientID)
		if err != nil {
			tx.Rollback()
			return dtodomain.AssignmentResponse{}, err
		}
		assignmentUsers = append(assignmentUsers, entities.TAssignmentUserEntity{
			AssignmentID: created.ID,
			TaskType:     userReq.TaskType,
			UserID:       userUUID,
			RoleID:       roleUUID,
			ClientID:     clientUUID,
		})
	}
	if len(assignmentUsers) > 0 {
		if err := s.assignmentUserRepo.BulkCreate(ctx, tx, assignmentUsers); err != nil {
			tx.Rollback()
			return dtodomain.AssignmentResponse{}, err
		}
	}
	tx.Commit()
	result, err := s.assignmentRepo.GetById(ctx, nil, created.ID.String())
	if err != nil {
		return dtodomain.AssignmentResponse{}, err
	}
	return toAssignmentResponse(result), nil
}

func (s *assignmentService) GetById(ctx context.Context, id string) (dtodomain.AssignmentResponse, error) {
	assignment, err := s.assignmentRepo.GetById(ctx, nil, id)
	if err != nil {
		return dtodomain.AssignmentResponse{}, err
	}
	return toAssignmentResponse(assignment), nil
}

func (s *assignmentService) GetAll(ctx context.Context, filter query.AssignmentFilter) ([]dtodomain.AssignmentResponse, int64, error) {
	assignments, total, err := s.assignmentRepo.GetAll(ctx, filter)
	if err != nil {
		return nil, 0, err
	}
	var responses []dtodomain.AssignmentResponse
	for _, e := range assignments {
		responses = append(responses, toAssignmentResponse(e))
	}
	if responses == nil {
		responses = make([]dtodomain.AssignmentResponse, 0)
	}
	return responses, total, nil
}

func (s *assignmentService) Update(ctx context.Context, req dtodomain.AssignmentUpdateRequest, id string) (dtodomain.AssignmentResponse, error) {
	tx := s.db.Begin()
	defer func() {
		if r := recover(); r != nil {
			tx.Rollback()
		}
	}()
	assignment, err := s.assignmentRepo.GetById(ctx, tx, id)
	if err != nil {
		tx.Rollback()
		return dtodomain.AssignmentResponse{}, err
	}
	if req.DocumentType != "" {
		assignment.DocumentType = req.DocumentType
	}
	if req.DocumentID != "" {
		docUUID, err := uuid.Parse(req.DocumentID)
		if err == nil {
			assignment.DocumentID = docUUID
		}
	}
	updated, err := s.assignmentRepo.Update(ctx, tx, assignment)
	if err != nil {
		tx.Rollback()
		return dtodomain.AssignmentResponse{}, err
	}
	tx.Commit()
	result, err := s.assignmentRepo.GetById(ctx, nil, updated.ID.String())
	if err != nil {
		return dtodomain.AssignmentResponse{}, err
	}
	return toAssignmentResponse(result), nil
}

func (s *assignmentService) Delete(ctx context.Context, id string) error {
	tx := s.db.Begin()
	defer func() {
		if r := recover(); r != nil {
			tx.Rollback()
		}
	}()
	if err := s.assignmentRepo.Delete(ctx, tx, id); err != nil {
		tx.Rollback()
		return err
	}
	tx.Commit()
	return nil
}

func NewAssignmentService(db *gorm.DB, assignmentRepo repository.AssignmentRepository, assignmentUserRepo repository.AssignmentUserRepository) AssignmentService {
	return &assignmentService{
		db:                 db,
		assignmentRepo:     assignmentRepo,
		assignmentUserRepo: assignmentUserRepo,
	}
}