package api

import (
	"encoding/json"
	"errors"
	"net/http"

	"git.fabledsword.com/bvandeusen/minstrel/internal/apierror"
	"git.fabledsword.com/bvandeusen/minstrel/internal/db/dbq"
	"git.fabledsword.com/bvandeusen/minstrel/internal/notifications"
)

// notificationEmailBody is the wire shape for GET and PUT
// /api/admin/notification-email (M489 #5346): when the grouped emails go out.
type notificationEmailBody struct {
	SummaryHour        int32 `json:"summary_hour"`
	BatchWindowMinutes int32 `json:"batch_window_minutes"`
}

func notificationEmailBodyOf(s notifications.EmailSettings) notificationEmailBody {
	return notificationEmailBody{SummaryHour: s.SummaryHour, BatchWindowMinutes: s.BatchWindowMinutes}
}

// handleGetNotificationEmail implements GET /api/admin/notification-email.
func (h *handlers) handleGetNotificationEmail(w http.ResponseWriter, r *http.Request) {
	s, err := notifications.LoadEmailSettings(r.Context(), dbq.New(h.pool))
	if err != nil {
		writeErrWithLog(w, h.logger, "admin notification email: load failed", apierror.Internal(err))
		return
	}
	writeJSON(w, http.StatusOK, notificationEmailBodyOf(s))
}

// handleUpdateNotificationEmail implements PUT /api/admin/notification-email.
// A whole-row write; the digest reads it on its next tick.
func (h *handlers) handleUpdateNotificationEmail(w http.ResponseWriter, r *http.Request) {
	var req notificationEmailBody
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		writeErr(w, apierror.BadRequest("invalid_body", "malformed JSON"))
		return
	}
	saved, err := notifications.SaveEmailSettings(r.Context(), dbq.New(h.pool), notifications.EmailSettings{
		SummaryHour:        req.SummaryHour,
		BatchWindowMinutes: req.BatchWindowMinutes,
	})
	if err != nil {
		if errors.Is(err, notifications.ErrEmailSettingOutOfRange) {
			writeErr(w, apierror.BadRequest("invalid_setting", err.Error()))
			return
		}
		writeErrWithLog(w, h.logger, "admin notification email: update failed", apierror.Internal(err))
		return
	}
	writeJSON(w, http.StatusOK, notificationEmailBodyOf(saved))
}