// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: PolyForm-Noncommercial-1.0.0

package admin

import (
	"fmt"
	"maps"
	"net/http"
	"slices"
	"strconv"
	"strings"

	"sourcedock.dev/petrbalvin/interpres/v2"
	"sourcedock.dev/petrbalvin/volumen/internal/payloads"
	"sourcedock.dev/petrbalvin/volumen/internal/templates"
)

// templateFields are the editor inputs a template may pre-fill beyond
// its title, slug, tags and body; anything else in the fields box is a
// typo waiting to seed every new post with a key nobody reads.
var templateFields = map[string]bool{
	"lang": true, "author": true, "fediverse_creator": true,
	"doi": true, "orcid": true,
	"series": true, "series_order": true,
	"excerpt": true, "cover": true, "cover_alt": true, "cover_caption": true,
}

// parseTemplateFields reads the fields box: key = value lines in TOML,
// each key an editor field. unknown names the first key outside the
// allowed set; err reports text that is not a small TOML document.
func parseTemplateFields(text string) (fields map[string]string, unknown string, err error) {
	if strings.TrimSpace(text) == "" {
		return nil, "", nil
	}
	data, err := interpres.ParseMap([]byte(text))
	if err != nil {
		return nil, "", fmt.Errorf("template fields must be key = value lines")
	}
	out := map[string]string{}
	for _, key := range slices.Sorted(maps.Keys(data)) {
		if !templateFields[key] {
			return nil, key, nil
		}
		value := data[key]
		if value == nil {
			continue
		}
		if text, isString := value.(string); isString {
			if text == "" {
				continue
			}
			out[key] = text
			continue
		}
		if number, isInt := value.(int64); isInt {
			out[key] = strconv.FormatInt(number, 10)
			continue
		}
		out[key] = fmt.Sprintf("%v", value)
	}
	if len(out) == 0 {
		return nil, "", nil
	}
	return out, "", nil
}

func (a *Admin) handleSettingsTemplateCreate(w http.ResponseWriter, r *http.Request) {
	if !a.requireCSRF(w, r) {
		return
	}
	name := strings.TrimSpace(r.PostFormValue("name"))
	if name == "" {
		a.renderSettings(w, r, a.tr(r, "Template name is required."), "", http.StatusUnprocessableEntity)
		return
	}
	fields, unknown, err := parseTemplateFields(r.PostFormValue("fields"))
	switch {
	case err != nil:
		a.renderSettings(w, r, a.tr(r, "Template fields must be key = value TOML lines."), "", http.StatusUnprocessableEntity)
		return
	case unknown != "":
		a.renderSettings(w, r, a.trf(r, "Unknown template field %s.", unknown), "", http.StatusUnprocessableEntity)
		return
	}
	if _, err := a.deps.Templates.Add(templates.PostTemplate{
		Name:   name,
		Tags:   payloads.ParseTags(r.PostFormValue("tags")),
		Body:   r.PostFormValue("body"),
		Title:  strings.TrimSpace(r.PostFormValue("title")),
		Slug:   strings.TrimSpace(r.PostFormValue("slug")),
		Fields: fields,
	}); err != nil {
		a.renderSettings(w, r, a.trf(r, "That template could not be added: %s", err.Error()), "", http.StatusUnprocessableEntity)
		return
	}
	a.renderSettings(w, r, "", a.tr(r, "Template added."), http.StatusOK)
}

func (a *Admin) handleSettingsTemplateDelete(w http.ResponseWriter, r *http.Request) {
	if !a.requireCSRF(w, r) {
		return
	}
	if err := a.deps.Templates.Delete(r.PathValue("name")); err != nil {
		a.renderSettings(w, r, a.trf(r, "The template could not be deleted: %s", err.Error()), "", http.StatusUnprocessableEntity)
		return
	}
	a.renderSettings(w, r, "", a.tr(r, "Template deleted."), http.StatusOK)
}

// --- backup export / import -------------------------------------------------

// handleSettingsWebhookTest delivers a ping inline and reports the
// outcome from the delivery it produced, not from the shared history a
// concurrent delivery could reshuffle.
func (a *Admin) handleSettingsWebhookTest(w http.ResponseWriter, r *http.Request) {
	if !a.requireCSRF(w, r) {
		return
	}
	if a.deps.Webhooks == nil {
		a.renderSettings(w, r, a.tr(r, "No webhooks configured."), "", http.StatusUnprocessableEntity)
		return
	}
	// The list is taken once: a settings change that reshuffles it between
	// the bounds check and the fetch would test a different hook than the
	// one the form named.
	hooks := a.deps.Webhooks.Hooks()
	index, err := strconv.Atoi(r.PathValue("index"))
	if err != nil || index < 0 || index >= len(hooks) {
		a.renderSettings(w, r, a.tr(r, "Webhook not found."), "", http.StatusUnprocessableEntity)
		return
	}
	hook := hooks[index]
	delivery := a.deps.Webhooks.TestHook(hook)
	a.record(r, "webhook.tested", hook.URL, nil)
	notice := a.tr(r, "Test delivery failed.")
	if delivery.Status == "ok" {
		notice = a.tr(r, "Test delivery sent.")
	}
	a.renderSettings(w, r, "", notice, http.StatusOK)
}

func (a *Admin) handleSettingsTokenCreate(w http.ResponseWriter, r *http.Request) {
	if !a.requireCSRF(w, r) {
		return
	}
	created, raw, err := a.deps.Tokens.Create(r.PostFormValue("name"), r.PostForm["scope"])
	if err != nil {
		a.renderSettings(w, r, a.trf(r, "The token could not be created: %s", err.Error()), "", http.StatusUnprocessableEntity)
		return
	}
	a.record(r, "token.created", created.Name, nil)
	data := a.settingsData(r)
	data.NewToken = raw
	a.renderPage(w, r, "settings.html", data, http.StatusOK)
}

func (a *Admin) handleSettingsTokenDelete(w http.ResponseWriter, r *http.Request) {
	if !a.requireCSRF(w, r) {
		return
	}
	name := r.PathValue("name")
	notice := a.tr(r, "Token revoked.")
	if !a.deps.Tokens.Revoke(name) {
		notice = a.tr(r, "That token was not found.")
	} else {
		a.record(r, "token.revoked", name, nil)
	}
	a.renderSettings(w, r, "", notice, http.StatusOK)
}