# -*- coding: utf-8 -*-
"""
分析一个 ocr_result.jsonl，判断"冗余文字过多"是真冗余还是误杀。
复现过滤逻辑：看文字的垂直位置分布(distinct_bands)、每帧文字框数、有没有稳定字幕行。

用法:  python temp/analyze_ocr_result.py "ocr_result (1).jsonl"
"""
import json
import sys
from collections import defaultdict

PATH = sys.argv[1] if len(sys.argv) > 1 else "ocr_result.jsonl"


def parse(path):
    """解析 'pic_path: X' + json 交替格式，返回 [(frame, detections), ...]。"""
    pairs = []
    cur_frame = None
    with open(path, encoding="utf-8") as f:
        for line in f:
            line = line.rstrip("\n")
            if line.startswith("pic_path:"):
                cur_frame = line.split("pic_path:", 1)[1].strip()
            elif line.strip():
                try:
                    data = json.loads(line)
                    pairs.append((cur_frame, data.get("TextDetections", [])))
                except json.JSONDecodeError:
                    pass
    return pairs


def center_y(det):
    poly = det.get("Polygon", [])
    ys = [p.get("Y", 0) for p in poly]
    return sum(ys) / len(ys) if ys else 0


def main():
    try:
        pairs = parse(PATH)
    except FileNotFoundError:
        print(f"找不到文件: {PATH}")
        return
    if not pairs:
        print("没解析到数据(格式不对?)")
        return

    n_frames = len(pairs)
    boxes_per_frame = [len(d) for _, d in pairs]
    total_boxes = sum(boxes_per_frame)
    frames_with_text = sum(1 for b in boxes_per_frame if b)

    # 所有文字框的中心 Y
    all_cy = []
    for _, dets in pairs:
        for det in dets:
            all_cy.append(center_y(det))

    print(f"文件: {PATH}")
    print("=" * 60)
    print(f"帧/图数:        {n_frames}")
    print(f"有文字的:       {frames_with_text}")
    print(f"文字框总数:     {total_boxes}")
    print(f"平均每帧框数:   {total_boxes / n_frames:.1f}")
    print(f"最多一帧框数:   {max(boxes_per_frame) if boxes_per_frame else 0}")

    # distinct vertical bands(复现 merge.py 的冗余判定：中心Y间隔>80算一个新垂直簇)
    cys = sorted(all_cy)
    bands = 1 if cys else 0
    for i in range(1, len(cys)):
        if cys[i] - cys[i - 1] > 80:
            bands += 1
    print(f"不同垂直位置簇: {bands}   (>=8 会被判冗余)")

    # Y 分布直方图(每 100px 一档)，看文字集中在哪还是散布全屏
    hist = defaultdict(int)
    for y in all_cy:
        hist[int(y // 100) * 100] += 1
    print("\n文字垂直分布(Y每100px一档，看文字集中度):")
    if hist:
        mx = max(hist.values())
        for y in sorted(hist):
            bar = "#" * int(hist[y] / mx * 40)
            print(f"  y={y:>5}-{y+99:<5} {hist[y]:>6}  {bar}")

    # 判定
    print("\n" + "=" * 60)
    if bands >= 8:
        print(f"❌ 真冗余：文字散布在 {bands} 个不同垂直位置(满屏文字/弹幕/文档类)。")
    elif total_boxes / n_frames > 10:
        print(f"⚠️ 偏冗余：平均每帧 {total_boxes/n_frames:.0f} 个文字框，画面文字很多。")
    else:
        topy = max(hist, key=hist.get) if hist else 0
        print(f"✅ 可能误杀：文字主要集中在 y={topy}~{topy+99}，像是有固定字幕行的。")
        print("   若确实有正常字幕，可放宽 merge.py 的 distinct_bands 阈值。")


if __name__ == "__main__":
    main()