#pragma once

#include <cassert>
#include <animation/animation_frame.h>
#include <animation/sprite_frame_cache.h>
#include <string>
#include <vector>

namespace extra2d {

// ============================================================================
// AnimationClip - 动画片段（纯数据，可复用）
// 借鉴 Cocos：一份 AnimationClip 可被多个 AnimationNode 同时使用
// ============================================================================
class AnimationClip {
public:
  AnimationClip() = default;

  explicit AnimationClip(const std::string &name) : name_(name) {}

  // ------ 帧管理 ------
  void addFrame(const AnimationFrame &frame) { frames_.push_back(frame); }

  void addFrame(AnimationFrame &&frame) { frames_.push_back(std::move(frame)); }

  void insertFrame(size_t index, const AnimationFrame &frame) {
    assert(index <= frames_.size());
    frames_.insert(frames_.begin() + static_cast<ptrdiff_t>(index), frame);
  }

  void removeFrame(size_t index) {
    assert(index < frames_.size());
    frames_.erase(frames_.begin() + static_cast<ptrdiff_t>(index));
  }

  void clearFrames() { frames_.clear(); }

  const AnimationFrame &getFrame(size_t index) const {
    assert(index < frames_.size());
    return frames_[index];
  }

  AnimationFrame &getFrame(size_t index) {
    assert(index < frames_.size());
    return frames_[index];
  }

  size_t getFrameCount() const { return frames_.size(); }
  bool empty() const { return frames_.empty(); }

  // ------ 全局属性（对应原始 AnimationFlag）------
  FramePropertySet &globalProperties() { return globalProperties_; }
  const FramePropertySet &globalProperties() const { return globalProperties_; }

  bool isLooping() const {
    return globalProperties_.getOr<bool>(FramePropertyKey::Loop, false);
  }

  void setLooping(bool loop) { globalProperties_.withLoop(loop); }

  // ------ 时间信息 ------
  float getTotalDuration() const {
    float total = 0.0f;
    for (const auto &frame : frames_) {
      total += frame.delay;
    }
    return total;
  }

  // ------ 预计算最大帧尺寸 ------
  Size getMaxFrameSize() const {
    Size maxSize;
    for (const auto &frame : frames_) {
      if (frame.spriteFrame && frame.spriteFrame->isValid()) {
        const auto &rect = frame.spriteFrame->getRect();
        if (rect.size.width > maxSize.width)
          maxSize.width = rect.size.width;
        if (rect.size.height > maxSize.height)
          maxSize.height = rect.size.height;
      }
    }
    return maxSize;
  }

  // ------ 元数据 ------
  void setName(const std::string &name) { name_ = name; }
  const std::string &getName() const { return name_; }

  void setSourcePath(const std::string &path) { sourcePath_ = path; }
  const std::string &getSourcePath() const { return sourcePath_; }

  // ------ 静态工厂 ------
  static Ptr<AnimationClip> create(const std::string &name = "") {
    return makePtr<AnimationClip>(name);
  }

  /// 从精灵图网格创建（所有帧按顺序）
  static Ptr<AnimationClip> createFromGrid(Ptr<Texture> texture, int frameWidth,
                                           int frameHeight,
                                           float frameDurationMs = 100.0f,
                                           int frameCount = -1, int spacing = 0,
                                           int margin = 0) {
    if (!texture)
      return nullptr;

    int texW = texture->getWidth();
    int texH = texture->getHeight();
    int usableW = texW - 2 * margin;
    int usableH = texH - 2 * margin;
    int cols = (usableW + spacing) / (frameWidth + spacing);
    int rows = (usableH + spacing) / (frameHeight + spacing);
    int total = (frameCount > 0) ? frameCount : cols * rows;

    auto clip = makePtr<AnimationClip>();
    for (int i = 0; i < total; ++i) {
      int col = i % cols;
      int row = i / cols;
      if (row >= rows)
        break;

      // 翻转行顺序：精灵图第0行在顶部，但OpenGL纹理V坐标从底部开始
      // 所以将行索引翻转，使第0行对应纹理底部（V=1.0），第3行对应纹理顶部（V=0.0）
      int flippedRow = (rows - 1) - row;

      Rect rect(
          static_cast<float>(margin + col * (frameWidth + spacing)),
          static_cast<float>(margin + flippedRow * (frameHeight + spacing)),
          static_cast<float>(frameWidth), static_cast<float>(frameHeight));

      auto sf = SpriteFrame::create(texture, rect);
      AnimationFrame frame;
      frame.spriteFrame = std::move(sf);
      frame.delay = frameDurationMs;
      clip->addFrame(std::move(frame));
    }
    return clip;
  }

  /// 从精灵图网格创建（指定帧索引列表）
  static Ptr<AnimationClip>
  createFromGridIndices(Ptr<Texture> texture, int frameWidth, int frameHeight,
                        const std::vector<int> &frameIndices,
                        float frameDurationMs = 100.0f, int spacing = 0,
                        int margin = 0) {
    if (!texture)
      return nullptr;

    int texW = texture->getWidth();
    int texH = texture->getHeight();
    int usableW = texW - 2 * margin;
    int usableH = texH - 2 * margin;
    int cols = (usableW + spacing) / (frameWidth + spacing);
    int rows = (usableH + spacing) / (frameHeight + spacing);

    auto clip = makePtr<AnimationClip>();
    for (int idx : frameIndices) {
      int col = idx % cols;
      int row = idx / cols;

      // 翻转行顺序：精灵图第0行在顶部，但OpenGL纹理V坐标从底部开始
      int flippedRow = (rows - 1) - row;

      Rect rect(
          static_cast<float>(margin + col * (frameWidth + spacing)),
          static_cast<float>(margin + flippedRow * (frameHeight + spacing)),
          static_cast<float>(frameWidth), static_cast<float>(frameHeight));

      auto sf = SpriteFrame::create(texture, rect);
      AnimationFrame frame;
      frame.spriteFrame = std::move(sf);
      frame.delay = frameDurationMs;
      clip->addFrame(std::move(frame));
    }
    return clip;
  }

private:
  std::string name_;
  std::string sourcePath_;
  std::vector<AnimationFrame> frames_;
  FramePropertySet globalProperties_;
};

} // namespace extra2d