#pragma once

#include <glacier/container/array.h>
#include <glacier/container/array_view.h>
#include <glacier/container/intrusive_list.h>
#include <glacier/container/linked_list.h>
#include <glacier/container/vector.h>
#include <glacier/memory/ref_ptr.h>
#include <glacier/memory/shared_ptr.h>
#include <glacier/status/error.h>
#include <glacier/status/error_or.h>

#include "capability/capability.h"
#include "include/ztypes.h"
#include "object/mutex.h"

struct IpcMessage {
  glcr::Array<uint8_t> data;

  glcr::Vector<glcr::RefPtr<Capability>> caps;

  glcr::RefPtr<Capability> reply_cap;
};

class MessageQueue {
 public:
  virtual ~MessageQueue() {}

  virtual glcr::ErrorCode PushBack(IpcMessage&&) = 0;
  virtual glcr::ErrorOr<IpcMessage> PopFront(uint64_t data_buf_size,
                                             uint64_t cap_buf_size) = 0;
  virtual bool empty() = 0;

 protected:
  glcr::RefPtr<Mutex> mutex_ = Mutex::Create();
  // FIXME: This maybe shouldn't be shared between classes since the
  // SingleMessageQueue should only ever have one blocked thread.
  glcr::IntrusiveList<Thread> blocked_threads_;
};

class UnboundedMessageQueue : public MessageQueue {
 public:
  UnboundedMessageQueue() {}
  UnboundedMessageQueue(const UnboundedMessageQueue&) = delete;
  UnboundedMessageQueue& operator=(const UnboundedMessageQueue&) = delete;
  virtual ~UnboundedMessageQueue() override {}

  glcr::ErrorCode PushBack(IpcMessage&& message) override;
  glcr::ErrorOr<IpcMessage> PopFront(uint64_t data_buf_size,
                                     uint64_t cap_buf_size) override;

  void WriteKernel(uint64_t init, glcr::RefPtr<Capability> cap);

  bool empty() override {
    MutexHolder h(mutex_);
    return pending_messages_.size() == 0;
  }

 private:
  glcr::LinkedList<IpcMessage> pending_messages_;
};

class SingleMessageQueue : public MessageQueue {
 public:
  SingleMessageQueue() {}
  SingleMessageQueue(const SingleMessageQueue&) = delete;
  SingleMessageQueue(SingleMessageQueue&&) = delete;
  virtual ~SingleMessageQueue() override {}

  glcr::ErrorCode PushBack(IpcMessage&&) override;
  glcr::ErrorOr<IpcMessage> PopFront(uint64_t data_buf_size,
                                     uint64_t cap_buf_size) override;

  bool empty() override {
    MutexHolder h(mutex_);
    return has_written_ == false;
  };

 private:
  bool has_written_ = false;
  bool has_read_ = false;
  IpcMessage message_;
};