package ghl

import (
	"context"
	"encoding/json"
	"io"
	"log/slog"
	"net/http"
	"time"

	"github.com/go-chi/chi/v5"
)

// LocationConfigStore is the store interface used by AdminHandler.
type LocationConfigStore interface {
	UpdateSenderID(ctx context.Context, locationID, senderID string) error
}

// AdminHandler exposes internal management endpoints.
// All routes require a valid Authorization: Bearer <adminKey> header.
type AdminHandler struct {
	adminKey string
	store    LocationConfigStore
}

func NewAdminHandler(adminKey string, store LocationConfigStore) *AdminHandler {
	return &AdminHandler{adminKey: adminKey, store: store}
}

// HandleSetSenderID sets or clears the per-location Cast sender ID.
//
//	PUT /api/admin/locations/{locationId}/sender-id
//	Authorization: Bearer <INBOUND_API_KEY>
//	{"sender_id":"CAST"}
func (h *AdminHandler) HandleSetSenderID(w http.ResponseWriter, r *http.Request) {
	if h.adminKey == "" || r.Header.Get("Authorization") != "Bearer "+h.adminKey {
		http.Error(w, "unauthorized", http.StatusUnauthorized)
		return
	}

	locationID := chi.URLParam(r, "locationId")
	if locationID == "" {
		http.Error(w, "missing locationId", http.StatusBadRequest)
		return
	}

	body, err := io.ReadAll(io.LimitReader(r.Body, 1024))
	if err != nil {
		http.Error(w, "failed to read body", http.StatusBadRequest)
		return
	}

	var payload struct {
		SenderID string `json:"sender_id"`
	}
	if err := json.Unmarshal(body, &payload); err != nil {
		http.Error(w, "invalid JSON", http.StatusBadRequest)
		return
	}

	ctx, cancel := context.WithTimeout(r.Context(), 10*time.Second)
	defer cancel()

	if err := h.store.UpdateSenderID(ctx, locationID, payload.SenderID); err != nil {
		slog.Error("admin: failed to update sender_id", "location_id", locationID, "err", err)
		if err.Error() == "location not found" {
			http.Error(w, "location not found", http.StatusNotFound)
			return
		}
		http.Error(w, "internal error", http.StatusInternalServerError)
		return
	}

	slog.Info("admin: sender_id updated", "location_id", locationID, "sender_id", payload.SenderID)
	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusOK)
	_, _ = w.Write([]byte(`{"ok":true}`))
}