package api

import (
	"context"
	"net/http"
	"strings"

	"git.golem15.com/golem15/sm-seo-plugin/classes"
	"git.golem15.com/golem15/sm-seo-plugin/models"
	"gorm.io/gorm"
)

// ListAutolinksInput is the query of GET /_seo/api/v1/autolinks.
type ListAutolinksInput struct {
	Page    int    `json:"page,omitempty" query:"page" jsonschema:"the page number, from 1"`
	PerPage int    `json:"per_page,omitempty" query:"per_page" jsonschema:"rows per page, at most 200 (50 by default)"`
	Search  string `json:"search,omitempty" query:"search" jsonschema:"text the phrase or the address contains"`
	Locale  string `json:"locale,omitempty" query:"locale" jsonschema:"a content locale code, or all for the phrases of every locale"`
	Origin  string `json:"origin,omitempty" query:"origin" jsonschema:"manual, keyphrase or mcp"`
	Active  string `json:"active,omitempty" query:"active" jsonschema:"true: active phrases only; false: inactive ones only"`
}

// CreateAutolinkInput is the body of POST /_seo/api/v1/autolinks.
type CreateAutolinkInput struct {
	Phrase  string  `json:"phrase" jsonschema:"the phrase texts link at its first occurrence (whole words, any letter case), at least 3 characters"`
	URL     string  `json:"url" jsonschema:"the address it links to: a path such as /grzyby/lwia-grzywa or a full http(s) address"`
	Locale  *string `json:"locale,omitempty" jsonschema:"the content locale it applies in; empty or all for every locale (the default)"`
	Enabled *bool   `json:"enabled,omitempty" jsonschema:"whether texts link it (default true)"`
	Note    *string `json:"note,omitempty" jsonschema:"an internal note"`
}

// UpdateAutolinkInput is PUT /_seo/api/v1/autolinks/{id}: only the fields
// sent change.
type UpdateAutolinkInput struct {
	ID      uint    `json:"id" path:"id" jsonschema:"the auto-link id"`
	Phrase  *string `json:"phrase,omitempty" jsonschema:"the phrase, at least 3 characters"`
	URL     *string `json:"url,omitempty" jsonschema:"a path or a full http(s) address"`
	Locale  *string `json:"locale,omitempty" jsonschema:"a content locale code; empty or all for every locale"`
	Enabled *bool   `json:"enabled,omitempty" jsonschema:"whether texts link it"`
	Note    *string `json:"note,omitempty" jsonschema:"an internal note"`
}

// DeleteAutolinksInput is the query of DELETE /_seo/api/v1/autolinks.
type DeleteAutolinksInput struct {
	IDs string `json:"ids" query:"ids" jsonschema:"the auto-link ids to delete, comma-separated, e.g. 3,4"`
}

// AutolinksFromKeyphrasesInput is POST /_seo/api/v1/autolinks/from-keyphrases
// (no fields).
type AutolinksFromKeyphrasesInput struct{}

// AutolinkJSON is an auto-link in an answer; locale is "" for every
// locale.
func AutolinkJSON(a models.Autolink) map[string]any {
	out := classes.AutolinkValues(a)
	out["id"] = a.ID
	out["created_at"] = a.CreatedAt
	out["updated_at"] = a.UpdatedAt
	return out
}

// ListAutolinks serves GET /_seo/api/v1/autolinks: by phrase, filtered by
// search text, locale, origin and the active state.
func ListAutolinks(service func() *classes.Service) http.HandlerFunc {
	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
		db, err := read(ctx, svc)
		if err != nil {
			return 0, nil, err
		}
		in := listParams(r)
		q := db.Model(&models.Autolink{}).Order("lower(phrase) ASC, locale ASC, id ASC")
		if in.Search != "" {
			p := like(in.Search)
			q = q.Where("lower(phrase) LIKE ? OR lower(url) LIKE ?", p, p)
		}
		query := r.URL.Query()
		if l := strings.TrimSpace(query.Get("locale")); l != "" {
			if l == models.AutolinkLocaleAll {
				l = ""
			}
			q = q.Where("locale = ?", l)
		}
		if o := strings.TrimSpace(query.Get("origin")); o != "" {
			q = q.Where("origin = ?", o)
		}
		switch strings.TrimSpace(query.Get("active")) {
		case "true", "1":
			q = q.Where("enabled")
		case "false", "0":
			q = q.Where("NOT enabled")
		}
		var rows []models.Autolink
		total, err := paginate(q, in, &rows)
		if err != nil {
			return 0, nil, err
		}
		out := make([]map[string]any, 0, len(rows))
		for _, row := range rows {
			out = append(out, AutolinkJSON(row))
		}
		return http.StatusOK, listBody(out, in, total), nil
	})
}

// CreateAutolink serves POST /_seo/api/v1/autolinks: 201 with the phrase,
// 422 validation_failed for a short phrase, an invalid address or a
// phrase the locale has (UI-SPEC C22). The origin is mcp through MCP.
func CreateAutolink(service func() *classes.Service) http.HandlerFunc {
	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
		var body CreateAutolinkInput
		if err := decode(r, maxBody, &body); err != nil {
			return 0, nil, err
		}
		row := models.NewAutolink()
		row.Origin = classes.AutolinkOrigin(ctx)
		classes.AutolinkWrite{Phrase: &body.Phrase, URL: &body.URL, Locale: body.Locale, Enabled: body.Enabled, Note: body.Note}.Apply(&row)
		err := write(ctx, svc, func(ctx context.Context, tx *gorm.DB) error {
			return svc.SaveAutolink(ctx, tx, &row)
		})
		if err != nil {
			return 0, nil, err
		}
		return http.StatusCreated, map[string]any{"data": AutolinkJSON(row)}, nil
	})
}

// UpdateAutolink serves PUT /_seo/api/v1/autolinks/{id}: the fields sent
// change, checked like a create.
func UpdateAutolink(service func() *classes.Service) http.HandlerFunc {
	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
		id, err := pathID(r, "id")
		if err != nil {
			return 0, nil, err
		}
		var body classes.AutolinkWrite
		if err := decode(r, maxBody, &body); err != nil {
			return 0, nil, err
		}
		var row models.Autolink
		err = write(ctx, svc, func(ctx context.Context, tx *gorm.DB) error {
			var err error
			if row, err = classes.LoadAutolink(tx, id); err != nil {
				return err
			}
			body.Apply(&row)
			return svc.SaveAutolink(ctx, tx, &row)
		})
		if err != nil {
			return 0, nil, err
		}
		return http.StatusOK, map[string]any{"data": AutolinkJSON(row)}, nil
	})
}

// DeleteAutolinks serves DELETE /_seo/api/v1/autolinks?ids=: the phrases
// named, each recorded in history; unknown ids are skipped.
func DeleteAutolinks(service func() *classes.Service) http.HandlerFunc {
	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
		ids, err := idList(r.URL.Query().Get("ids"))
		if err != nil {
			return 0, nil, err
		}
		var deleted []uint
		err = write(ctx, svc, func(ctx context.Context, tx *gorm.DB) error {
			var err error
			deleted, err = svc.DeleteAutolinks(ctx, tx, ids)
			return err
		})
		if err != nil {
			return 0, nil, err
		}
		return http.StatusOK, map[string]any{"deleted": deleted}, nil
	})
}

// AutolinksFromKeyphrases serves POST
// /_seo/api/v1/autolinks/from-keyphrases: one phrase per record whose
// focus keyphrase in a locale is not yet a phrase there (origin
// keyphrase), with the count added and the toast text.
func AutolinksFromKeyphrases(service func() *classes.Service) http.HandlerFunc {
	return manage(service, func(ctx context.Context, svc *classes.Service, r *http.Request) (int, any, error) {
		added := 0
		err := write(ctx, svc, func(ctx context.Context, tx *gorm.DB) error {
			var err error
			added, err = svc.FromKeyphrases(ctx, tx)
			return err
		})
		if err != nil {
			return 0, nil, err
		}
		message := svc.PhraseCtx(ctx, "golem15.seo::lang.autolinks.keyphrases_none", nil)
		if added > 0 {
			message = svc.ChoiceCtx(ctx, "golem15.seo::lang.autolinks.keyphrases_added", added, nil)
		}
		return http.StatusOK, map[string]any{"added": added, "message": message}, nil
	})
}