#!/usr/bin/env python3
"""Strip in-figure titles from checked-in SVGs and crop top whitespace.

按學術規範：圖本身不包含標題（標題寫在正文）。本指令碼保守地處理
`images/` 中已簽入的 SVG 檔案。

判定規則（保守）：
- 第一處出現的 <text> 元素，若同時滿足：font-size>=20 且 y<60 且 text-anchor=middle，
  則視為圖示題——刪除該元素，並將 viewBox 上沿和 height 各下移/縮小 CROP_PX。
- 否則該檔案不做任何修改。

用法：python3 strip_titles.py [--dry-run]
"""

import os
import re
import sys

IMAGES_DIR = os.path.join(os.path.dirname(__file__), 'images')
CROP_PX = 40

TEXT_RE = re.compile(
    r'<text\b([^>]*?)>(.*?)</text>',
    flags=re.DOTALL,
)
ATTR_RE = re.compile(r'(\w[\w-]*)\s*=\s*"([^"]*)"')
SVG_TAG_RE = re.compile(r'<svg\b([^>]*)>', flags=re.DOTALL)
VIEWBOX_RE = re.compile(r'viewBox="([^"]+)"')
HEIGHT_ATTR_RE = re.compile(r'\bheight="([^"]+)"')


def parse_attrs(attr_str):
    return {m.group(1): m.group(2) for m in ATTR_RE.finditer(attr_str)}


def process_file(path, dry_run=False):
    with open(path, 'r', encoding='utf-8') as f:
        content = f.read()

    # 找第一個 <text>
    m = TEXT_RE.search(content)
    if not m:
        return 'no-text'
    attrs = parse_attrs(m.group(1))
    fs = float(attrs.get('font-size', '0') or 0)
    y = float(attrs.get('y', '0') or 0)
    anchor = attrs.get('text-anchor', '')
    if not (fs >= 20 and y < 60 and anchor == 'middle'):
        return 'no-title'

    # 刪除該 <text> 元素
    new_content = content[: m.start()] + content[m.end():]

    # 調整 viewBox 與 height
    svg_m = SVG_TAG_RE.search(new_content)
    if not svg_m:
        return 'no-svg-tag'
    svg_attrs_str = svg_m.group(1)

    def replace_viewbox(vbm):
        parts = vbm.group(1).split()
        if len(parts) != 4:
            return vbm.group(0)
        x0, y0, w, h = parts
        try:
            new_y0 = float(y0) + CROP_PX
            new_h = float(h) - CROP_PX
        except ValueError:
            return vbm.group(0)
        def fmt(v):
            return str(int(v)) if v == int(v) else str(v)
        return f'viewBox="{fmt(float(x0))} {fmt(new_y0)} {fmt(float(w))} {fmt(new_h)}"'

    new_svg_attrs = VIEWBOX_RE.sub(replace_viewbox, svg_attrs_str)

    def replace_height(hm):
        try:
            new_h = float(hm.group(1)) - CROP_PX
            new_h_s = str(int(new_h)) if new_h == int(new_h) else str(new_h)
            return f'height="{new_h_s}"'
        except ValueError:
            return hm.group(0)

    new_svg_attrs = HEIGHT_ATTR_RE.sub(replace_height, new_svg_attrs, count=1)
    new_content = new_content[:svg_m.start()] + f'<svg{new_svg_attrs}>' + new_content[svg_m.end():]

    if not dry_run:
        with open(path, 'w', encoding='utf-8') as f:
            f.write(new_content)
    return 'stripped'


def main():
    dry_run = '--dry-run' in sys.argv
    counts = {'stripped': 0, 'no-title': 0, 'no-text': 0, 'no-svg-tag': 0}
    examples = {k: [] for k in counts}
    for name in sorted(os.listdir(IMAGES_DIR)):
        if not name.endswith('.svg'):
            continue
        result = process_file(os.path.join(IMAGES_DIR, name), dry_run=dry_run)
        counts[result] = counts.get(result, 0) + 1
        if len(examples[result]) < 5:
            examples[result].append(name)
    mode = '[DRY-RUN]' if dry_run else '[APPLIED]'
    print(f'{mode} summary:')
    for k, v in counts.items():
        print(f'  {k}: {v}  e.g. {examples[k]}')


if __name__ == '__main__':
    main()