/*
 * Copyright 2026 Joel Klinghed
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#include "xcb_colors.hh"

#include "xcb_connection.hh"
#include "xcb_event.hh"

#include <cassert>
#include <cstddef>
#include <cstdint>
#include <map>
#include <memory>
#include <utility>
#include <vector>
#include <xcb/xproto.h>

namespace xcb {

namespace {

class ColorsImpl : public Colors {
 public:
  ColorsImpl(shared_conn conn, xcb_colormap_t colormap)
      : conn_(std::move(conn)),
        colormap_(colormap),
        storage_(std::make_shared<StorageImpl>()) {}

  Color get_with_fallback(uint8_t r, uint8_t g, uint8_t b,
                          uint32_t fallback) override {
    auto key = make_key(r, g, b);
    auto it = index_.find(key);
    size_t index;
    if (it == index_.end()) {
      index = cookie_.size();
      cookie_.push_back(xcb_alloc_color(
          conn_.get(), colormap_, static_cast<uint16_t>(r) << 8,
          static_cast<uint16_t>(g) << 8, static_cast<uint16_t>(b) << 8));
      fallback_.push_back(fallback);
      index_.emplace(key, index);
    } else {
      index = it->second;
    }
    return {storage_, index};
  }

  bool sync() override {
    std::vector<uint32_t> colors;
    colors.reserve(cookie_.size());
    for (size_t i = 0; i < cookie_.size(); ++i) {
      xcb::reply<xcb_alloc_color_reply_t> reply(
          xcb_alloc_color_reply(conn_.get(), cookie_[i], nullptr));
      if (reply) {
        colors.push_back(reply->pixel);
      } else {
        colors.push_back(fallback_[i]);
      }
    }
    storage_->set(std::move(colors));
    return true;
  }

 private:
  class StorageImpl : public Storage {
   public:
    [[nodiscard]]
    uint32_t get(size_t id) const override {
      assert(id < resolved_.size());
      return resolved_[id];
    }

    void set(std::vector<uint32_t> resolved) {
      resolved_ = std::move(resolved);
    }

   private:
    std::vector<uint32_t> resolved_;
  };

  static uint32_t make_key(uint8_t r, uint8_t g, uint8_t b) {
    return static_cast<uint32_t>(r) << 16 | static_cast<uint32_t>(g) << 8 | b;
  }

  shared_conn conn_;
  xcb_colormap_t colormap_;
  std::map<uint32_t, size_t> index_;
  std::vector<xcb_alloc_color_cookie_t> cookie_;
  std::vector<uint32_t> fallback_;
  std::shared_ptr<StorageImpl> storage_;
};

}  // namespace

std::unique_ptr<Colors> Colors::create(shared_conn conn,
                                       xcb_colormap_t colormap) {
  return std::make_unique<ColorsImpl>(std::move(conn), colormap);
}

}  // namespace xcb