"""PDF helper for the STCourses importer. Run as: python -I pdf_tool.py render <pdf> <outdir> [--width 1280] [--quality 80]

Writes outdir/p-001.jpg ... and outdir/text.json ([{"page": 1, "text": "..."}]).
Prints one "page N/M" line per page on stdout and a final JSON line {"pages": M, "title": "..."}.
"""
import json
import os
import sys

try:
    import pymupdf as fitz
except ImportError:  # older PyMuPDF
    import fitz


def render(pdf, outdir, width, quality):
    os.makedirs(outdir, exist_ok=True)
    doc = fitz.open(pdf)
    n = len(doc)
    texts = []
    for i, page in enumerate(doc, start=1):
        zoom = width / max(page.rect.width, 1)
        pix = page.get_pixmap(matrix=fitz.Matrix(zoom, zoom), alpha=False)
        pix.save(os.path.join(outdir, "p-%03d.jpg" % i), jpg_quality=quality)
        texts.append({"page": i, "text": page.get_text().strip()})
        print("page %d/%d" % (i, n), flush=True)
    with open(os.path.join(outdir, "text.json"), "w", encoding="utf-8") as f:
        json.dump(texts, f, ensure_ascii=False)
    print(json.dumps({"pages": n, "title": (doc.metadata or {}).get("title") or ""}), flush=True)


def main(argv):
    if len(argv) < 4 or argv[1] != "render":
        print("usage: pdf_tool.py render <pdf> <outdir> [--width N] [--quality N]", file=sys.stderr)
        return 2
    width, quality = 1280, 80
    rest = argv[4:]
    while rest:
        flag, val = rest[0], rest[1] if len(rest) > 1 else ""
        if flag == "--width":
            width = int(val)
        elif flag == "--quality":
            quality = int(val)
        rest = rest[2:]
    render(argv[2], argv[3], width, quality)
    return 0


if __name__ == "__main__":
    sys.exit(main(sys.argv))