package classes

import (
	"context"
	"strings"

	"git.golem15.com/golem15/sm-seo-plugin/models"
	"git.golem15.com/golem15/sm-sitemap-plugin/contract"
)

// SiteAnswer is the answer of GET /_seo/api/v1/site (P33-17): the facts
// about the whole site the frontend layer needs, all public. SiteURL,
// DefaultLocale, Locales and UnprefixedLocale are the resolver's; Links
// the settings' new-tab switch; HTMLSitemap the sitemap plugin's HTML
// sitemap settings; Routes each content type's layered URL pattern for
// the layer's drift check; RootFiles the file names the layer serves at
// the site root (verification files, the IndexNow key file); LLMS whether
// /llms.txt is served; Pagination the site's page address form and
// HomeCrumb the home crumb (33-06, D-40, D-86).
type SiteAnswer struct {
	SiteURL          string          `json:"site_url"`
	DefaultLocale    string          `json:"default_locale"`
	Locales          []string        `json:"locales"`
	UnprefixedLocale string          `json:"unprefixed_locale"`
	Links            SiteLinks       `json:"links"`
	HTMLSitemap      SiteHTMLSitemap `json:"html_sitemap"`
	Routes           []SiteRoute     `json:"routes"`
	RootFiles        []string        `json:"root_files"`
	LLMS             bool            `json:"llms"`
	Pagination       SitePagination  `json:"pagination"`
	HomeCrumb        SiteHomeCrumb   `json:"home_crumb"`
}

// SitePagination is the site answer's pagination block: the form (query
// or path), the query parameter and the path segment per locale, so the
// layer builds numbered links and checks drift.
type SitePagination struct {
	Form     string            `json:"form"`
	Param    string            `json:"param"`
	Segments map[string]string `json:"segments"`
}

// SiteHomeCrumb is the home crumb: its name in the default locale, the
// home URL and the name per locale.
type SiteHomeCrumb struct {
	Name  string            `json:"name"`
	URL   string            `json:"url"`
	Names map[string]string `json:"names"`
}

// SiteLinks is the site answer's links block.
type SiteLinks struct {
	NewTab bool `json:"new_tab"`
}

// SiteHTMLSitemap is the site answer's HTML sitemap block: whether the
// sitemap plugin serves it, its path per locale and its page size.
type SiteHTMLSitemap struct {
	Enabled  bool              `json:"enabled"`
	Paths    map[string]string `json:"paths"`
	PageSize int               `json:"page_size"`
}

// SiteRoute is one content type's URL pattern.
type SiteRoute struct {
	Type    string `json:"type"`
	Pattern string `json:"pattern"`
}

// listing returns the sitemap plugin's published contract.Listing, nil
// when none is published.
func (s *Service) listing() contract.Listing {
	if s == nil || s.app == nil {
		return nil
	}
	l, ok := s.app.Lookup[contract.Listing]()
	if !ok {
		return nil
	}
	return l
}

// Site builds the site answer. It names only public facts: no token, no
// unpublished data (T-33-19).
func (s *Service) Site(ctx context.Context) (SiteAnswer, error) {
	out := SiteAnswer{
		SiteURL:          s.SiteURL(),
		UnprefixedLocale: s.UnprefixedLocale(),
		HTMLSitemap:      SiteHTMLSitemap{Paths: map[string]string{}},
		Routes:           []SiteRoute{},
		RootFiles:        []string{},
	}
	db, err := s.DB(ctx)
	if err != nil {
		return out, err
	}
	settings, err := LoadSettings(db)
	if err != nil {
		return out, err
	}
	robots, err := LoadRobots(db)
	if err != nil {
		return out, err
	}
	out.DefaultLocale = s.DefaultLocale(ctx, db)
	out.Locales = s.Locales(ctx, db)
	out.Links.NewTab = settings.LinksNewTab
	out.LLMS = robots.LlmsEnabled
	pages := s.PageConfigOf(ctx, db, settings)
	out.Pagination = SitePagination{Form: pages.Form, Param: PageParam, Segments: pages.Segments}
	out.HomeCrumb = SiteHomeCrumb{URL: out.SiteURL + "/", Names: map[string]string{}}
	for _, locale := range out.Locales {
		out.HomeCrumb.Names[locale] = s.HomeCrumbName(ctx, db, settings, locale)
	}
	out.HomeCrumb.Name = out.HomeCrumb.Names[out.DefaultLocale]
	if reg := s.Registry(); reg != nil {
		for _, typ := range reg.ContentTypes() {
			if typ.Key == PageTypeKey {
				continue
			}
			out.Routes = append(out.Routes, SiteRoute{Type: typ.Key, Pattern: reg.Pattern(typ.Key, "")})
		}
	}
	seen := map[string]bool{}
	addFile := func(name string) {
		name = strings.TrimSpace(name)
		if name != "" && verificationName.MatchString(name) && !seen[name] {
			seen[name] = true
			out.RootFiles = append(out.RootFiles, name)
		}
	}
	for _, f := range settings.Files() {
		addFile(f.Filename)
	}
	if l := s.listing(); l != nil {
		st, err := l.Settings(ctx)
		if err != nil {
			return out, err
		}
		out.HTMLSitemap.Enabled = st.HTMLEnabled
		for locale, path := range st.HTMLPaths {
			if strings.TrimSpace(path) != "" {
				out.HTMLSitemap.Paths[locale] = path
			}
		}
		out.HTMLSitemap.PageSize = st.HTMLPageSize
		addFile(st.KeyFile)
	}
	return out, nil
}

// SiteName is the site's name in locale: the settings' site name, else
// the application name.
func (s *Service) SiteName(ctx context.Context, settings models.Settings, locale string) string {
	db, err := s.DB(ctx)
	name := settings.SiteName
	if err == nil {
		name = s.translatedSetting(ctx, db, &settings, "site_name", settings.SiteName, locale)
	}
	if strings.TrimSpace(name) == "" {
		if cfg := s.Config(); cfg != nil {
			name = cfg.String("app.name")
		}
	}
	return strings.TrimSpace(name)
}