import os
import sys
import shutil
from PIL import Image

big_images_path = "/data/vjuicefs_ai_camera_llm/intern_data/minxing/datasets/UltraLens/200mm"
Lens="85mm"
ORIGINAL_IMAGES_PATH = f'/data/vjuicefs_ai_camera_llm/intern_data/minxing/datasets/UltraLens_final/{Lens}/val/gt_1024'
ANNOTATIONS_PATH = '/data/vjuicefs_ai_camera_llm/intern_data/minxing/datasets/UltraLens/Anno'
OUTPUT_JSON_PATH = f'/data/vjuicefs_ai_camera_llm/intern_data/minxing/datasets/UltraLens_final/{Lens}/val/Anno_below1024'

# 开关：是否复制标注
COPY_ANNOTATIONS = True

IMG_EXTS = {'.jpg', '.jpeg', '.png', '.bmp', '.tif', '.tiff', '.webp'}
ANN_EXT = '_res.json'

def is_image_file(fname: str) -> bool:
    return os.path.splitext(fname.lower())[1] in IMG_EXTS

def get_image_size(img_path: str):
    try:
        with Image.open(img_path) as im:
            w, h = im.size
        return w, h
    except Exception as e:
        print(f'[WARN] 打开图像失败: {img_path} -> {e}')
        return None

def ensure_dir(path: str):
    os.makedirs(path, exist_ok=True)

def collect_filenames_from_dir(root_dir: str):
    """
    返回：set [不含扩展名的文件名] 和 dict 映射 [basename(含扩展) -> 相对路径]
    """
    names_no_ext = set()
    rel_map = {}
    for root, _, files in os.walk(root_dir):
        for f in files:
            if is_image_file(f):
                rel = os.path.relpath(os.path.join(root, f), root_dir)
                rel_map[f] = rel
                names_no_ext.add(os.path.splitext(f)[0])
    return names_no_ext, rel_map

def index_images_by_basename(root_dir: str):
    """
    构建 big_images_path 的索引：basename(含扩展) -> [绝对路径列表]
    """
    idx = {}
    for root, _, files in os.walk(root_dir):
        for f in files:
            if is_image_file(f):
                idx.setdefault(f, []).append(os.path.join(root, f))
    return idx

def build_ann_index(ann_root: str):
    """
    标注文件名(含扩展) -> [绝对路径列表]
    """
    idx = {}
    for root, _, files in os.walk(ann_root):
        for f in files:
            if f.lower().endswith(ANN_EXT):
                idx.setdefault(f, []).append(os.path.join(root, f))
    return idx

def main():
    ensure_dir(OUTPUT_JSON_PATH)
    # 1) 从 ORIGINAL_IMAGES_PATH 收集文件名
    names_no_ext, original_rel_map = collect_filenames_from_dir(ORIGINAL_IMAGES_PATH)
    print(f'[INFO] ORIGINAL 中图像基名数量：{len(names_no_ext)}；示例若干：{list(sorted(list(names_no_ext))[:5])}')

    # 2) 建立 big_images_path 的 basename 索引
    big_idx = index_images_by_basename(big_images_path)
    print(f'[INFO] big_images_path 中索引的文件名数：{len(big_idx)}')

    # 3) 可选：建立标注索引
    ann_idx = build_ann_index(ANNOTATIONS_PATH) if COPY_ANNOTATIONS else {}

    total_to_check = 0
    checked = 0
    below_1024 = 0
    copied_ann = 0
    missing_in_big = 0
    missing_ann = 0

    # 统计可能的扩展名对应关系（相同基名不同扩展）
    # 对 ORIGINAL 中的每个基名，尝试在 big_images_path 中匹配任意同名基名文件（不论扩展）
    for base_no_ext in names_no_ext:
        # 找 big_images_path 中所有与该基名匹配的文件（不同扩展）
        candidates = []
        for ext in IMG_EXTS:
            fname = base_no_ext + ext
            if fname in big_idx:
                candidates.extend(big_idx[fname])

        if not candidates:
            missing_in_big += 1
            continue

        total_to_check += len(candidates)
        for img_path in candidates:
            size = get_image_size(img_path)
            if size is None:
                continue
            checked += 1
            w, h = size
            if max(w, h) <= 1024:
                below_1024 += 1

                if COPY_ANNOTATIONS:
                    ann_name = base_no_ext + ANN_EXT
                    # 首选同名标注
                    ann_candidates = ann_idx.get(ann_name, [])
                    if not ann_candidates:
                        missing_ann += 1
                        continue
                    # 目标路径：保留 ANNOTATIONS_PATH 下的相对结构（如果可解析），否则直接平铺到输出根或使用图像相对路径
                    # 尝试用第一个候选
                    ann_src = ann_candidates[0]
                    # 如果候选在 ANNOTATIONS_PATH 下，使用相对路径保存
                    if ann_src.startswith(os.path.abspath(ANNOTATIONS_PATH)):
                        rel = os.path.relpath(ann_src, ANNOTATIONS_PATH)
                        ann_dst = os.path.join(OUTPUT_JSON_PATH, rel)
                    else:
                        # 回退：将其放到输出根目录
                        ann_dst = os.path.join(OUTPUT_JSON_PATH, ann_name)

                    ensure_dir(os.path.dirname(ann_dst))
                    try:
                        shutil.copy2(ann_src, ann_dst)
                        copied_ann += 1
                    except Exception as e:
                        print(f'[ERROR] 复制失败: {ann_src} -> {ann_dst} | {e}')

    print('---- 统计 ----')
    print(f'ORIGINAL 中基名数：{len(names_no_ext)}')
    print(f'在 big_images_path 中缺失的基名数：{missing_in_big}')
    print(f'需要检查的同名文件数：{total_to_check}')
    print(f'成功读取尺寸的文件数：{checked}')
    print(f'最长边<=1024 的文件数：{below_1024}')
    if COPY_ANNOTATIONS:
        print(f'成功复制标注数：{copied_ann}')
        print(f'缺失标注数：{missing_ann}')
        print(f'输出标注目录：{OUTPUT_JSON_PATH}')

if __name__ == '__main__':
    try:
        from PIL import Image  # 确认 Pillow 已安装
    except ImportError:
        print('请先安装 Pillow: pip install pillow')
        sys.exit(1)
    main()