package pages

import (
	"context"
	"errors"
	"lmika.dev/lmika/hugo-cms/models"
	"lmika.dev/lmika/hugo-cms/providers/db"
	"lmika.dev/lmika/hugo-cms/services/jobs"
	"lmika.dev/lmika/hugo-cms/services/sitebuilder"
	"lmika.dev/pkg/modash/moslice"
	"strings"
	"time"
	"unicode"
)

type Service struct {
	db   *db.DB
	sb   *sitebuilder.Service
	jobs *jobs.Service
}

func New(
	db *db.DB,
	sb *sitebuilder.Service,
	jobs *jobs.Service,
) *Service {
	return &Service{
		db:   db,
		sb:   sb,
		jobs: jobs,
	}
}

func (s *Service) ListPagesOfSite(ctx context.Context, site models.Site) ([]models.Page, error) {
	return s.db.ListPagesOfSite(ctx, site.ID)
}

func (s *Service) GetPage(ctx context.Context, id int) (models.Page, error) {
	post, err := s.db.GetPage(ctx, int64(id))
	if err != nil {
		return models.Page{}, err
	}

	return post, nil
}

func (s *Service) DeletePage(ctx context.Context, site models.Site, id int) error {
	post, err := s.db.GetPage(ctx, int64(id))
	if err != nil {
		return err
	}

	if err := s.db.DeletePage(ctx, int64(id)); err != nil {
		return err
	}

	return s.jobs.Queue(ctx, s.sb.DeletePage(site, post))
}

func (s *Service) Create(ctx context.Context, site models.Site, req NewPost) (models.Page, error) {
	siteBundles, err := s.db.ListBundles(ctx, site.ID)
	if err != nil {
		return models.Page{}, err
	} else if len(siteBundles) == 0 {
		return models.Page{}, errors.New("no bundles found")
	}

	rootBundle, ok := moslice.FindWhere(siteBundles, func(t models.Bundle) bool {
		return t.Name == models.RootBundleName
	})
	if !ok {
		return models.Page{}, errors.New("root bundle not found")
	}

	publishTime := time.Now()

	name := s.normalizePageName(req.Title)
	nameProvenance := models.TitleNameProvenance
	if name == "" {
		// Use the timestamp as the name
		name = publishTime.Format("2006-01-02-150405")
		nameProvenance = models.DateNameProvenance
	}

	post := models.Page{
		SiteID:         site.ID,
		BundleID:       rootBundle.ID,
		Name:           name,
		NameProvenance: nameProvenance,
		Title:          req.Title,
		Body:           req.Body,
		State:          models.PostStatePublished,
		PublishDate:    time.Now(),
	}

	if err := s.save(ctx, site, rootBundle, &post); err != nil {
		return models.Page{}, err
	}

	return post, nil
}

func (s *Service) Update(ctx context.Context, site models.Site, pageID int64, req NewPost) (models.Page, error) {
	page, err := s.db.GetPage(ctx, pageID)
	if err != nil {
		return models.Page{}, err
	}

	if page.SiteID != site.ID {
		return models.Page{}, errors.New("page not found")
	}

	bundle, err := s.db.GetBundleWithID(ctx, page.BundleID)
	if err != nil {
		return models.Page{}, err
	} else if bundle.SiteID != site.ID {
		return models.Page{}, errors.New("page not found")
	}

	// Update the title if it wasn't set by the user
	if page.NameProvenance != models.UserNameProvenance {
		if req.Title == "" {
			page.Name = page.PublishDate.Format("2006-01-02-150405")
			page.NameProvenance = models.DateNameProvenance
		} else {
			page.Name = s.normalizePageName(req.Title)
			page.NameProvenance = models.TitleNameProvenance
		}
	}
	page.Title = req.Title
	page.Body = req.Body

	if err := s.save(ctx, site, bundle, &page); err != nil {
		return models.Page{}, err
	}

	return page, nil
}

func (s *Service) save(ctx context.Context, site models.Site, bundle models.Bundle, page *models.Page) error {
	page.SiteID = site.ID

	if page.ID == 0 {
		page.CreatedAt = time.Now()
		page.UpdatedAt = time.Now()
		if err := s.db.InsertPage(ctx, page); err != nil {
			return err
		}
	} else {
		page.UpdatedAt = time.Now()
		if err := s.db.UpdatePage(ctx, page); err != nil {
			return err
		}
	}

	return s.jobs.Queue(ctx, s.sb.WritePage(site, bundle, *page))
}

func (s *Service) normalizePageName(title string) string {
	var sb strings.Builder
	lastSpace := false
	for _, r := range title {
		switch {
		case unicode.IsSpace(r):
			if !lastSpace {
				sb.WriteRune('-')
				lastSpace = true
			}
		case unicode.IsNumber(r):
			lastSpace = false
			sb.WriteRune(r)
		case unicode.IsLetter(r):
			lastSpace = false
			sb.WriteRune(unicode.ToLower(r))
		}
	}
	return sb.String()
}

type NewPost struct {
	Title string
	Body  string
}