// Copyright (c) 2026 Juhapekka Piiroinen <jp@1337.fi>
// All Rights Reserved.
// AmoosedWeb project: https://amoosed.com
#pragma once
#include "AmoosedWeb/Reader.hpp"
#include <atomic>
#include <functional>
#include <string>
#include <string_view>

namespace amoosed {
// A caller transport runs synchronously on the Reader's worker thread. Its
// response owns its bytes until the callback returns; the adapter copies them
// before exposing them to the verified Reader. The callback must not call this
// host recursively. Cancellation may be signalled from another thread. A
// blocked callback must arrange its own wakeup before cancellation can return.
struct CallbackRequest {
  enum class Kind { Range, Suffix, Complete } kind;
  std::string_view path;
  std::size_t first = 0, last = 0, max_body = 0;
};
struct CallbackResponse {
  int status = 0;
  std::string final_url, content_range, etag, content_encoding;
  std::vector<std::uint8_t> body;
};
using HttpCallback = std::function<bool(const CallbackRequest&, CallbackResponse&,
                                        std::string&)>;

class CallbackHttpHost final : public HttpHost {
 public:
  CallbackHttpHost(std::string origin, HttpCallback callback);
  void cancel() noexcept override { cancelled_.store(true); }
  void reset_cancel() noexcept override { cancelled_.store(false); }
  bool cancelled() const override { return cancelled_.load(); }
  bool fetch_range(std::string_view path, std::size_t first, std::size_t last,
                   std::size_t max_body, FetchResponse& response,
                   std::string& error) override;
  bool fetch_suffix(std::string_view path, std::size_t length,
                    std::size_t max_body, FetchResponse& response,
                    std::string& error) override;
  bool fetch_complete(std::string_view path, std::size_t max_body,
                      FetchResponse& response, std::string& error) override;
 private:
  bool fetch(CallbackRequest request, FetchResponse& response,
             std::string& error);
  std::string origin_;
  HttpCallback callback_;
  std::atomic_bool cancelled_{false};
};
}