// MÓDULO 2.1: APPOINTMENTS - /appointments/cancel
import { validateExternalAuth } from "../_shared/auth.ts";

const corsHeaders = {
  "Access-Control-Allow-Origin": "*",
  "Access-Control-Allow-Headers":
    "authorization, x-client-info, apikey, content-type",
};

function externalRest(path: string, method: string, body?: any): Promise<any> {
  const url = `${Deno.env.get("EXTERNAL_SUPABASE_URL")}/rest/v1/${path}`;
  return fetch(url, {
    method,
    headers: {
      "Content-Type": "application/json",
      apikey: Deno.env.get("EXTERNAL_SUPABASE_KEY")!,
      Authorization: `Bearer ${Deno.env.get("EXTERNAL_SUPABASE_KEY")}`,
      Prefer: "return=representation",
    },
    body: body ? JSON.stringify(body) : undefined,
  }).then((r) => r.json());
}

Deno.serve(async (req) => {
  if (req.method === "OPTIONS")
    return new Response("ok", { headers: corsHeaders });

  try {
    const authHeader = req.headers.get("Authorization");
    const supabase = createClient(
      Deno.env.get("SUPABASE_URL")!,
      Deno.env.get("SUPABASE_ANON_KEY")!,
      { global: { headers: { Authorization: authHeader! } } }
    );

    const {
      data: { user },
    } = await supabase.auth.getUser();
    if (!user) throw new Error("Unauthorized");

    const { appointment_id, reason } = await req.json();

    // Buscar appointment para pegar doctor_id e date
    const appointment = await externalRest(
      `appointments?id=eq.${appointment_id}`,
      "GET"
    );
    const apt = appointment[0];

    // Cancelar no Supabase externo
    await externalRest(`appointments?id=eq.${appointment_id}`, "PATCH", {
      status: "cancelled",
      cancellation_reason: reason,
    });

    // Log
    await supabase.from("user_actions").insert({
      user_id: user.id,
      external_user_id: apt.patient_id,
      action_category: "appointment",
      action_type: "cancel",
      action_description: `Cancelled appointment ${appointment_id}`,
      resource_type: "appointment",
      resource_id: appointment_id,
    });

    // Adicionar próximo da waitlist se existir
    const { data: waitlistMatch } = await supabase
      .from("waitlist")
      .select("*")
      .eq("doctor_id", apt.doctor_id)
      .eq("status", "waiting")
      .order("priority", { ascending: false })
      .order("created_at", { ascending: true })
      .limit(1);

    if (waitlistMatch && waitlistMatch.length > 0) {
      // Notificar paciente da waitlist
      await supabase.from("notifications_queue").insert({
        recipient_id: waitlistMatch[0].patient_id,
        type: "sms",
        template: "waitlist_slot_available",
        data: {
          appointment_date: apt.appointment_date,
          appointment_time: apt.appointment_time,
        },
      });
    }

    return new Response(
      JSON.stringify({
        success: true,
        message: "Appointment cancelled",
        waitlist_notified: !!waitlistMatch,
      }),
      { headers: { ...corsHeaders, "Content-Type": "application/json" } }
    );
  } catch (error: any) {
    return new Response(
      JSON.stringify({ success: false, error: error.message }),
      {
        status: 400,
        headers: { ...corsHeaders, "Content-Type": "application/json" },
      }
    );
  }
});