"""
DOCX-Rendering und PDF-Konvertierung.
"""
from __future__ import annotations

import logging
import re
import subprocess
import tempfile
from pathlib import Path

from docx import Document
from docxtpl import DocxTemplate

logger = logging.getLogger(__name__)

PLACEHOLDER_RE = re.compile(r"\{\{\s*([A-Za-z_][A-Za-z0-9_]*)")


def extract_placeholders(docx_path: Path) -> list[str]:
    """Liest die Jinja-Platzhalter aus einem DOCX und gibt sie sortiert zurück."""
    doc = Document(str(docx_path))
    found: set[str] = set()
    for para in doc.paragraphs:
        for m in PLACEHOLDER_RE.finditer(para.text):
            found.add(m.group(1))
    for table in doc.tables:
        for row in table.rows:
            for cell in row.cells:
                for para in cell.paragraphs:
                    for m in PLACEHOLDER_RE.finditer(para.text):
                        found.add(m.group(1))
    return sorted(found)


def render_docx(template_path: Path, context: dict, out_path: Path) -> Path:
    """Füllt das DOCX-Template mit Kontext und schreibt das Ergebnis."""
    tpl = DocxTemplate(str(template_path))
    tpl.render(context)
    tpl.save(str(out_path))
    return out_path


def docx_to_pdf(docx_path: Path, out_dir: Path) -> Path:
    """Konvertiert DOCX nach PDF mit LibreOffice headless.

    LibreOffice braucht ein eigenes Profilverzeichnis, sonst kollidieren
    parallele Worker.
    """
    out_dir.mkdir(parents=True, exist_ok=True)
    with tempfile.TemporaryDirectory(prefix="lo-profile-") as profile_dir:
        cmd = [
            "soffice",
            "--headless",
            "--nologo",
            "--norestore",
            "--nolockcheck",
            f"-env:UserInstallation=file://{profile_dir}",
            "--convert-to", "pdf",
            "--outdir", str(out_dir),
            str(docx_path),
        ]
        logger.info("LibreOffice convert: %s", " ".join(cmd))
        result = subprocess.run(  # noqa: S603
            cmd, capture_output=True, text=True, timeout=120, check=False
        )
        if result.returncode != 0:
            raise RuntimeError(
                f"LibreOffice-Konvertierung fehlgeschlagen: {result.stderr}"
            )
    pdf_path = out_dir / (docx_path.stem + ".pdf")
    if not pdf_path.exists():
        raise FileNotFoundError(f"PDF nicht gefunden: {pdf_path}")
    return pdf_path