# -*- coding: utf-8 -*-
"""Batch fix for 课评汇总 class pages:
1) Remove the 评星 (star rating) feature: strip each <div class="metrics">…</div> block,
   delete star/metric CSS rules, and remove the dead star JS functions.
2) Fix the 翻页卡死 (pagination freeze) on carousel pages: switch slides from
   absolute-stacked opacity to display:none for inactive cards (only the active
   card is ever laid out/painted), and remove backdrop-filter blur (compositing cost).

Only applied to the first-week pages when <target> is the folder.
"""
import os, re, sys

# ------------- balanced <div class="metrics"> removal -------------
def remove_metrics(html):
    marker = '<div class="metrics">'
    res = []
    i = 0
    n = len(html)
    while True:
        idx = html.find(marker, i)
        if idx == -1:
            res.append(html[i:])
            break
        res.append(html[i:idx])
        depth = 1
        j = idx + len(marker)
        while depth > 0 and j < n:
            oi = html.find('<div', j)
            ci = html.find('</div>', j)
            if ci == -1:
                j = n
                break
            if oi != -1 and oi < ci:
                depth += 1
                j = oi + 4
            else:
                depth -= 1
                j = ci + 6
        i = j
    return ''.join(res)

# ------------- balanced CSS block parser -------------
def strip_css(css, is_carousel):
    out = []
    i = 0
    n = len(css)
    while i < n:
        m = re.match(r'\s+', css[i:])
        if m:
            out.append(m.group(0)); i += m.end(); continue
        m = re.match(r'/\*.*?\*/', css[i:], re.S)
        if m:
            out.append(m.group(0)); i += m.end(); continue
        brace = css.find('{', i)
        if brace == -1:
            out.append(css[i:]); break
        sel = css[i:brace]
        depth = 1
        j = brace + 1
        while depth > 0 and j < n:
            if css[j] == '{': depth += 1
            elif css[j] == '}': depth -= 1
            j += 1
        body = css[brace+1:j-1]
        full = css[i:j]
        selnorm = sel.strip()
        if selnorm.startswith('@media') or selnorm.startswith('@supports'):
            out.append(selnorm + '{' + strip_css(body, is_carousel) + '}')
        elif re.search(r'\.(?:metric|star)', selnorm):
            pass  # drop star / metric rules
        elif is_carousel and re.match(r'^\.student-card', selnorm):
            if '.prev' in selnorm:
                pass  # drop the now-unneeded prev-state rule
            elif '.active' in selnorm:
                out.append('.student-card.active { display: block; position: relative; pointer-events: auto; }')
            elif re.match(r'^\.student-card\s*$', selnorm):
                out.append('.student-card { display: none; }')
            else:
                out.append(full)  # .student-card:hover
        else:
            out.append(full)
        i = j
    return ''.join(out)

def process_styles(html, is_carousel):
    def repl(m):
        css = strip_css(m.group(2), is_carousel)
        css = re.sub(r'backdrop-filter\s*:\s*blur\([^)]*\);?', '', css)
        return m.group(1) + css + m.group(3)
    return re.sub(r'(<style[^>]*>)(.*?)(</style>)', repl, html, flags=re.S)

# ------------- dead star JS removal -------------
def remove_function(js, name):
    pat = re.compile(r'function\s+' + re.escape(name) + r'\s*\(')
    m = pat.search(js)
    if not m:
        return js
    brace = js.find('{', m.end())
    if brace == -1:
        return js
    depth = 1
    j = brace + 1
    n = len(js)
    while depth > 0 and j < n:
        if js[j] == '{': depth += 1
        elif js[j] == '}': depth -= 1
        j += 1
    return js[:m.start()] + js[j:]

def remove_call(js, name):
    return re.sub(r'^[ \t]*' + re.escape(name) + r'\(\).*?$', '', js, flags=re.M)

def fix(html):
    is_carousel = 'id="cardsSlider"' in html
    html = remove_metrics(html)
    html = process_styles(html, is_carousel)
    if 'function initStarRatings' in html and 'initStarRatings' in html:
        html = remove_call(html, 'initStarRatings')
        html = remove_function(html, 'initStarRatings')
        html = remove_function(html, 'setStarRating')
    return html

def main(files):
    for path in files:
        with open(path, encoding='utf-8') as f:
            html = f.read()
        out = fix(html)
        changed = out != html
        with open(path, 'w', encoding='utf-8') as f:
            f.write(out)
        print(('CHANGED ' if changed else 'same    ') + os.path.basename(path))

if __name__ == '__main__':
    main(sys.argv[1:])