#!/usr/bin/env python3
"""Compile a LaTeX project with cached Tectonic resources and shell escape disabled."""
from pathlib import Path
import re
import shutil
import subprocess
import sys
import tempfile

from _pdf_common import SkillArgumentParser, output_pdf, new_temp_pdf, publish_temp_file, run_cli


def compile_document(args):
    from pypdf import PdfReader
    source=Path(args.input).expanduser().resolve()
    if not source.is_file() or source.suffix.lower()!='.tex' or not 0 < source.stat().st_size <= 2*1024*1024:
        raise ValueError('输入需为不超过 2 MiB 的本地 .tex 文件')
    if not 1 <= args.timeout <= 600:
        raise ValueError('timeout 必须在 1–600 秒之间')
    executable=shutil.which('tectonic')
    if not executable:
        raise RuntimeError('基础镜像缺少预置 Tectonic，需要更新镜像')
    target=output_pdf(args.output,args.overwrite)
    temporary=new_temp_pdf(target)
    try:
        with tempfile.TemporaryDirectory(prefix='pdf-latex-') as folder:
            command=[executable,'--untrusted','--only-cached','--keep-logs','--outdir',folder,str(source)]
            completed=subprocess.run(command,cwd=source.parent,capture_output=True,text=True,timeout=args.timeout,check=False)
            result=Path(folder)/(source.stem+'.pdf')
            messages=(completed.stdout+'\n'+completed.stderr).splitlines()
            if completed.returncode or not result.is_file():
                detail='\n'.join(messages[-15:])
                raise RuntimeError('LaTeX 编译失败；缺失 TeX 包需在基础镜像构建时预置，任务中不下载：'+detail)
            count=len(PdfReader(result).pages)
            if not count:
                raise ValueError('LaTeX 没有生成有效 PDF')
            logfile=Path(folder)/(source.stem+'.log')
            if logfile.exists():
                messages += logfile.read_text(errors='replace').splitlines()
            warnings=list(dict.fromkeys(line.strip() for line in messages if re.search(r'warning:|Overfull|Missing character|undefined references',line,re.I)))[:30]
            shutil.copyfile(result,temporary)
        publish_temp_file(temporary,target,args.overwrite)
    finally:
        temporary.unlink(missing_ok=True)
    return {'source':str(source),'path':str(target),'page_count':count,'engine':'tectonic','dependency_mode':'cached-only',
            'warnings':warnings,'requires_visual_review':True}


def main(argv=None):
    parser=SkillArgumentParser(description='固定 LaTeX 编译接口，禁用 shell escape，只使用镜像内缓存包')
    parser.add_argument('--input',required=True); parser.add_argument('--output',required=True)
    parser.add_argument('--timeout',type=int,default=180); parser.add_argument('--overwrite',action='store_true')
    return run_cli(lambda:compile_document(parser.parse_args(sys.argv[1:] if argv is None else argv)))


if __name__=='__main__':
    raise SystemExit(main())