import { serve } from "https://deno.land/std@0.177.0/http/server.ts";
import { createSupabaseClient } from "../_shared/supabase-client.ts";
import { trySignR2Url, transformLegacyMediaUrl } from "../_shared/r2_signer.ts";

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

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

  if (req.method !== "POST") {
    return new Response(JSON.stringify({ error: "Method not allowed" }), {
      status: 405,
      headers: { ...corsHeaders, "Content-Type": "application/json" },
    });
  }

  try {
    const authHeader = req.headers.get("Authorization");
    if (!authHeader) {
      return new Response(JSON.stringify({ error: "Missing authorization header" }), {
        status: 401,
        headers: { ...corsHeaders, "Content-Type": "application/json" },
      });
    }

    const supabase = createSupabaseClient(authHeader);
    const {
      data: { user },
      error: authError,
    } = await supabase.auth.getUser();

    if (authError || !user) {
      return new Response(JSON.stringify({ error: "Unauthorized" }), {
        status: 401,
        headers: { ...corsHeaders, "Content-Type": "application/json" },
      });
    }

    const body = await req.json().catch(() => ({}));
    const url = body?.url as string | undefined;
    const key = body?.key as string | undefined;
    const expiresIn = Number.isFinite(body?.expiresIn) ? Number(body.expiresIn) : 3600;

    const target = key || url;
    if (!target) {
      return new Response(JSON.stringify({ error: "Missing url or key" }), {
        status: 400,
        headers: { ...corsHeaders, "Content-Type": "application/json" },
      });
    }

    // Transform legacy media.sojorn.net URLs to their object key
    const transformedTarget = transformLegacyMediaUrl(target) ?? target;

    const signedUrl = await trySignR2Url(transformedTarget, expiresIn);
    if (!signedUrl) {
      return new Response(JSON.stringify({ error: "Failed to sign media URL" }), {
        status: 400,
        headers: { ...corsHeaders, "Content-Type": "application/json" },
      });
    }

    return new Response(JSON.stringify({ signedUrl, signed_url: signedUrl }), {
      status: 200,
      headers: { ...corsHeaders, "Content-Type": "application/json" },
    });
  } catch (error) {
    const message = error instanceof Error ? error.message : "Internal server error";
    return new Response(JSON.stringify({ error: message }), {
      status: 500,
      headers: { ...corsHeaders, "Content-Type": "application/json" },
    });
  }
});
