package org

import (
	"context"
	"errors"
	"fmt"
	"strings"
)

var (
	ErrNotFound   = errors.New("organization not found")
	ErrSlugExists = errors.New("slug already taken")
)

type Service struct {
	repo *Repository
}

func NewService(repo *Repository) *Service {
	return &Service{repo: repo}
}

func (s *Service) Create(ctx context.Context, req CreateOrgRequest) (*Organization, error) {
	req.Slug = strings.ToLower(strings.TrimSpace(req.Slug))

	org := &Organization{
		Name: req.Name,
		Slug: req.Slug,
	}

	if err := s.repo.Create(ctx, org); err != nil {
		if isUniqueViolation(err) {
			return nil, ErrSlugExists
		}
		return nil, fmt.Errorf("failed to create organization: %w", err)
	}

	return org, nil
}

func (s *Service) GetByID(ctx context.Context, id string) (*Organization, error) {
	org, err := s.repo.FindByID(ctx, id)
	if err != nil {
		if errors.Is(err, ErrNoRows) {
			return nil, ErrNotFound
		}
		return nil, fmt.Errorf("failed to find organization: %w", err)
	}
	return org, nil
}

func (s *Service) List(ctx context.Context) (*OrgListResponse, error) {
	orgs, err := s.repo.FindAll(ctx)
	if err != nil {
		return nil, fmt.Errorf("failed to list organizations: %w", err)
	}
	if orgs == nil {
		orgs = []Organization{}
	}
	return &OrgListResponse{
		Organizations: orgs,
		Total:         len(orgs),
	}, nil
}

func (s *Service) Update(ctx context.Context, id string, req UpdateOrgRequest) (*Organization, error) {
	org, err := s.repo.FindByID(ctx, id)
	if err != nil {
		if errors.Is(err, ErrNoRows) {
			return nil, ErrNotFound
		}
		return nil, fmt.Errorf("failed to find organization: %w", err)
	}

	org.Name = req.Name

	if err := s.repo.Update(ctx, org); err != nil {
		return nil, fmt.Errorf("failed to update organization: %w", err)
	}

	return org, nil
}

func (s *Service) Delete(ctx context.Context, id string) error {
	org, err := s.repo.FindByID(ctx, id)
	if err != nil {
		if errors.Is(err, ErrNoRows) {
			return ErrNotFound
		}
		return fmt.Errorf("failed to find organization: %w", err)
	}

	if err := s.repo.Delete(ctx, org.ID); err != nil {
		return fmt.Errorf("failed to delete organization: %w", err)
	}

	return nil
}

func isUniqueViolation(err error) bool {
	return err != nil && (strings.Contains(err.Error(), "unique") || strings.Contains(err.Error(), "23505"))
}