package seo

import (
	"context"
	"sort"
	"time"

	"git.golem15.com/golem15/sm-seo-plugin/classes"
	"git.golem15.com/golem15/sm-seo-plugin/controllers"
	"git.golem15.com/golem15/sm-seo-plugin/models"
	"git.golem15.com/golem15/summercms/modules/pact"
)

// pagesFormYAML adds the translatable address and name to the Pages form
// (UI-SPEC C21): url after page_status, title after kind.
const pagesFormYAML = `fields:
    url:
        label: golem15.seo::lang.pages.url
        comment: golem15.seo::lang.pages.url_comment
        type: mltext
        span: left
        after: page_status
    title:
        label: golem15.seo::lang.pages.title
        comment: golem15.seo::lang.pages.title_comment
        type: mltext
        span: left
        after: kind
`

// pagesForm is the plugin's form extension on its own Pages controller:
// it loads and saves a page's address and name per locale (the default
// locale in the url and title columns, the others in urls and titles),
// refuses a page with the C21 copy (url_required, url_invalid, url_taken,
// url_owned) inside the save transaction, and records the save in
// history. It is listed before the SEO tab, so the tab's address tracking
// sees the saved address.
func (p *Plugin) pagesForm() *pact.AdminFormExtension {
	return &pact.AdminFormExtension{
		FieldsYAML:  []byte(pagesFormYAML),
		Permissions: []string{controllers.PermissionManage},
		Load: func(ctx context.Context, in pact.AdminFormLoad) (map[string]any, error) {
			svc := p.Service()
			if svc == nil {
				return nil, classes.ErrNotBooted
			}
			page, ok := in.Record.(*models.Page)
			if !ok || page == nil {
				return map[string]any{}, nil
			}
			db := in.DB.WithContext(ctx)
			def := svc.DefaultLocale(ctx, db)
			urls := map[string]string{}
			titles := map[string]string{}
			for _, locale := range svc.Locales(ctx, db) {
				urls[locale], titles[locale] = "", ""
			}
			for locale, path := range page.LocaleURLs(def) {
				urls[locale] = path
			}
			titles[def] = page.Title
			for locale, title := range page.Titles.Get() {
				if locale != def {
					titles[locale] = title
				}
			}
			return map[string]any{"url": urls, "title": titles}, nil
		},
		Save: func(ctx context.Context, in pact.AdminFormSave) (pact.AdminFormSaveResult, error) {
			svc := p.Service()
			if svc == nil {
				return pact.AdminFormSaveResult{}, classes.ErrNotBooted
			}
			page, ok := in.Record.(*models.Page)
			if !ok || page == nil {
				return pact.AdminFormSaveResult{}, nil
			}
			var before map[string]any
			if !in.Created {
				before = classes.PageValues(*page)
				old, _ := classes.ChangesValues(in.Changes, false)
				for k, v := range old {
					before[k] = v
				}
			}
			urls, urlsSent := localeTexts(in.Values["url"])
			titles, titlesSent := localeTexts(in.Values["title"])
			if !urlsSent {
				urls = nil
			}
			if !titlesSent {
				titles = nil
			}
			if err := svc.ApplyPageTexts(ctx, in.DB, page, urls, titles); err != nil {
				return pact.AdminFormSaveResult{}, err
			}
			problems, err := svc.CheckPage(ctx, in.DB, *page)
			if err != nil {
				return pact.AdminFormSaveResult{}, err
			}
			if list := problems["url"]; len(list) > 0 {
				refusals := pact.AdminFormErrors{}
				for _, pr := range list {
					refusals["url"] = append(refusals["url"], svc.PhraseCtx(ctx, pr.Key, pr.Params))
				}
				return pact.AdminFormSaveResult{}, refusals
			}
			if err := in.DB.Model(&models.Page{}).Where("id = ?", page.ID).Updates(map[string]any{
				"url": page.URL, "urls": page.URLs, "title": page.Title, "titles": page.Titles, "updated_at": time.Now().UTC(),
			}).Error; err != nil {
				return pact.AdminFormSaveResult{}, err
			}
			return pact.AdminFormSaveResult{}, svc.RecordPage(ctx, in.DB, before, *page, false)
		},
	}
}

// localeTexts reads a submitted translatable value as locale -> text;
// sent is false when the request did not send the field. A plain string
// is the default locale's ("" key).
func localeTexts(raw any) (map[string]string, bool) {
	switch v := raw.(type) {
	case nil:
		return nil, false
	case map[string]string:
		return v, true
	case map[string]any:
		out := make(map[string]string, len(v))
		keys := make([]string, 0, len(v))
		for k := range v {
			keys = append(keys, k)
		}
		sort.Strings(keys)
		for _, k := range keys {
			s, _ := v[k].(string)
			out[k] = s
		}
		return out, true
	case string:
		return map[string]string{"": v}, true
	}
	return nil, false
}