package com.example.livestreaming;

import android.graphics.Outline;
import android.net.Uri;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewOutlineProvider;

import androidx.annotation.NonNull;
import androidx.core.content.FileProvider;
import androidx.recyclerview.widget.DiffUtil;
import androidx.recyclerview.widget.ListAdapter;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.Glide;
import com.example.livestreaming.databinding.ItemConversationBinding;

public class ConversationsAdapter extends ListAdapter<ConversationItem, ConversationsAdapter.VH> {

    public interface OnConversationClickListener {
        void onConversationClick(ConversationItem item);
    }

    private final OnConversationClickListener onConversationClickListener;

    public ConversationsAdapter(OnConversationClickListener onConversationClickListener) {
        super(DIFF);
        this.onConversationClickListener = onConversationClickListener;
    }

    @NonNull
    @Override
    public VH onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        ItemConversationBinding binding = ItemConversationBinding.inflate(LayoutInflater.from(parent.getContext()), parent, false);
        return new VH(binding, onConversationClickListener);
    }

    @Override
    public void onBindViewHolder(@NonNull VH holder, int position) {
        holder.bind(getItem(position));
    }

    static class VH extends RecyclerView.ViewHolder {

        private final ItemConversationBinding binding;
        private final OnConversationClickListener onConversationClickListener;

        VH(ItemConversationBinding binding, OnConversationClickListener onConversationClickListener) {
            super(binding.getRoot());
            this.binding = binding;
            this.onConversationClickListener = onConversationClickListener;
        }

        void bind(ConversationItem item) {
            binding.title.setText(item != null && item.getTitle() != null ? item.getTitle() : "");
            binding.lastMessage.setText(item != null && item.getLastMessage() != null ? item.getLastMessage() : "");
            binding.timeText.setText(item != null && item.getTimeText() != null ? item.getTimeText() : "");

            int unread = item != null ? item.getUnreadCount() : 0;
            if (unread > 0) {
                binding.unreadBadge.setVisibility(View.VISIBLE);
                binding.unreadBadge.setText(unread > 99 ? "99+" : String.valueOf(unread));
            } else {
                binding.unreadBadge.setVisibility(View.GONE);
            }

            // 加载头像
            loadAvatar(item);

            binding.getRoot().setOnClickListener(v -> {
                if (item == null) return;
                if (onConversationClickListener != null) onConversationClickListener.onConversationClick(item);
            });
        }

        private void loadAvatar(ConversationItem item) {
            // TODO: 接入后端接口 - 加载会话对方头像
            // 接口路径: GET /api/users/{userId}/avatar 或直接从ConversationItem的avatarUrl字段获取
            // 如果ConversationItem对象包含avatarUrl字段，直接使用该URL加载头像
            // 如果没有avatarUrl，需要根据会话类型（私信/群聊）调用相应接口获取头像
            if (binding.avatar == null) return;
            
            // 设置圆形裁剪
            setupAvatarOutline();
            
            try {
                // 优先使用ConversationItem中的avatarUrl（从后端获取）
                // 尝试从 SharedPreferences 加载用户头像
                String avatarUri = binding.avatar.getContext()
                        .getSharedPreferences("profile_prefs", android.content.Context.MODE_PRIVATE)
                        .getString("profile_avatar_uri", null);
                
                if (!TextUtils.isEmpty(avatarUri)) {
                    // 尝试解析 URI
                    Uri uri = Uri.parse(avatarUri);
                    // 如果是 file:// 协议，尝试转换为 FileProvider URI
                    if ("file".equals(uri.getScheme())) {
                        try {
                            java.io.File file = new java.io.File(uri.getPath());
                            if (file.exists()) {
                                uri = FileProvider.getUriForFile(
                                    binding.avatar.getContext(),
                                    binding.avatar.getContext().getPackageName() + ".fileprovider",
                                    file
                                );
                            }
                        } catch (Exception e) {
                            // 如果转换失败，使用原始 URI
                        }
                    }
                    
                    Glide.with(binding.avatar)
                            .load(uri)
                            .circleCrop()
                            .error(R.drawable.ic_account_circle_24)
                            .placeholder(R.drawable.ic_account_circle_24)
                            .into(binding.avatar);
                    return;
                }
                
                int avatarRes = binding.avatar.getContext()
                        .getSharedPreferences("profile_prefs", android.content.Context.MODE_PRIVATE)
                        .getInt("profile_avatar_res", 0);
                
                if (avatarRes != 0) {
                    Glide.with(binding.avatar)
                            .load(avatarRes)
                            .circleCrop()
                            .error(R.drawable.ic_account_circle_24)
                            .placeholder(R.drawable.ic_account_circle_24)
                            .into(binding.avatar);
                    return;
                }
                
                // 如果没有保存的头像，使用默认头像
                Glide.with(binding.avatar)
                        .load(R.drawable.ic_account_circle_24)
                        .circleCrop()
                        .into(binding.avatar);
            } catch (Exception e) {
                // 如果加载失败，使用默认头像
                Glide.with(binding.avatar)
                        .load(R.drawable.ic_account_circle_24)
                        .circleCrop()
                        .into(binding.avatar);
            }
        }

        private void setupAvatarOutline() {
            if (binding.avatar == null) return;
            // 设置圆形裁剪，确保在模拟器上也能正常工作
            binding.avatar.post(() -> {
                if (binding.avatar.getWidth() > 0 && binding.avatar.getHeight() > 0) {
                    binding.avatar.setOutlineProvider(new ViewOutlineProvider() {
                        @Override
                        public void getOutline(View view, Outline outline) {
                            outline.setOval(0, 0, view.getWidth(), view.getHeight());
                        }
                    });
                    binding.avatar.setClipToOutline(true);
                }
            });
        }
    }

    private static final DiffUtil.ItemCallback<ConversationItem> DIFF = new DiffUtil.ItemCallback<ConversationItem>() {
        @Override
        public boolean areItemsTheSame(@NonNull ConversationItem oldItem, @NonNull ConversationItem newItem) {
            String o = oldItem.getId();
            String n = newItem.getId();
            return o != null && o.equals(n);
        }

        @Override
        public boolean areContentsTheSame(@NonNull ConversationItem oldItem, @NonNull ConversationItem newItem) {
            return oldItem.equals(newItem);
        }
    };
}