#!/usr/bin/env python3
"""
pipeline.py — Full PDF Accessibility Pipeline
==============================================

Runs both parts end-to-end:

  Part 1 · generate_metadata   (Python)
    PDF → YOLOv11 + Tesseract + GPT-4o → output/elements.txt

  Part 2 · embed_metadata      (Java / iText)
    input.pdf + elements.txt → output/tagged_output.pdf  (PDF/UA-1)

Usage
-----
    python pipeline.py                          # uses data/input.pdf
    python pipeline.py --pdf path/to/file.pdf
    python pipeline.py --pdf file.pdf --latex path/to/latex-project/
    python pipeline.py --skip-metadata          # only run Java tagger
    python pipeline.py --skip-tagging           # only run Python analysis
"""

import argparse
import os
import subprocess
import sys

ROOT       = os.path.dirname(os.path.abspath(__file__))
DATA_DIR   = os.path.join(ROOT, "data")
OUTPUT_DIR = os.path.join(ROOT, "output")
JAR_PATH   = os.path.join(ROOT, "pdftagger.jar")


def run(cmd: list, **kwargs):
    print(f"\n>>> {' '.join(str(c) for c in cmd)}")
    result = subprocess.run(cmd, **kwargs)
    if result.returncode != 0:
        sys.exit(result.returncode)
    return result


def build_jar(force: bool = False):
    if os.path.exists(JAR_PATH) and not force:
        print(f"[pipeline] JAR already built: {JAR_PATH}")
        return
    print("[pipeline] Building Java tagger JAR (maven package)…")
    run(["mvn", "-f", os.path.join(ROOT, "pom.xml"), "package", "-q", "-DskipTests"])
    if not os.path.exists(JAR_PATH):
        print("[pipeline] ERROR: pdftagger.jar not found after build.", file=sys.stderr)
        sys.exit(1)
    print(f"[pipeline] JAR built: {JAR_PATH}")


def main():
    parser = argparse.ArgumentParser(
        description="PDF Accessibility Pipeline — analyse then tag.",
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )
    parser.add_argument(
        "--pdf",
        default=os.path.join(DATA_DIR, "input.pdf"),
        help="Input PDF (default: data/input.pdf)",
    )
    parser.add_argument(
        "--latex",
        default=DATA_DIR,
        metavar="DIR",
        help="Directory containing the LaTeX source subfolder (default: data/). "
             "Place your .tex project as a subfolder inside data/ and this is detected automatically.",
    )
    parser.add_argument(
        "--output",
        default=OUTPUT_DIR,
        help="Output directory (default: output/)",
    )
    parser.add_argument(
        "--pages",
        type=int,
        default=-1,
        metavar="N",
        help="Limit to first N pages (-1 = all)",
    )
    parser.add_argument(
        "--skip-metadata",
        action="store_true",
        help="Skip Part 1 (use existing output/elements.txt)",
    )
    parser.add_argument(
        "--skip-tagging",
        action="store_true",
        help="Skip Part 2 (Java tagger)",
    )
    parser.add_argument(
        "--rebuild-jar",
        action="store_true",
        help="Force rebuild of pdftagger.jar before tagging",
    )
    parser.add_argument(
        "--no-preflight",
        action="store_true",
        help="Skip prerequisite checks (for CI/CD environments).",
    )
    args = parser.parse_args()

    from preflight import run_preflight_checks
    run_preflight_checks(
        skip=args.no_preflight,
        need_python_part=not args.skip_metadata,
        need_java_part=not args.skip_tagging,
    )

    pdf_path     = os.path.abspath(args.pdf)
    output_dir   = os.path.abspath(args.output)
    elements_out = os.path.join(output_dir, "elements.txt")
    tagged_out   = os.path.join(output_dir, "tagged_output.pdf")

    os.makedirs(output_dir, exist_ok=True)
    os.makedirs(os.path.join(output_dir, "visualizations"), exist_ok=True)

    if not os.path.exists(pdf_path):
        print(f"[pipeline] ERROR: PDF not found: {pdf_path}", file=sys.stderr)
        sys.exit(1)

    # ----------------------------------------------------------------
    # Part 1 — generate_metadata
    # ----------------------------------------------------------------
    if not args.skip_metadata:
        print("\n[pipeline] ═══ Part 1: Generate Metadata ═══")
        cmd = [
            sys.executable, "-m", "generate_metadata.main",
            "--pdf",    pdf_path,
            "--output", output_dir,
            "--pages",  str(args.pages),
        ]
        cmd += ["--latex", os.path.abspath(args.latex)]
        run(cmd, cwd=ROOT)

        if not os.path.exists(elements_out):
            print(f"[pipeline] ERROR: elements.txt not produced at {elements_out}", file=sys.stderr)
            sys.exit(1)
    else:
        print(f"[pipeline] Skipping Part 1 — using: {elements_out}")
        if not os.path.exists(elements_out):
            print(
                "[pipeline] ERROR: elements.txt not found. Run without --skip-metadata first.",
                file=sys.stderr,
            )
            sys.exit(1)

    # ----------------------------------------------------------------
    # Part 2 — embed_metadata (Java tagger)
    # ----------------------------------------------------------------
    if not args.skip_tagging:
        print("\n[pipeline] ═══ Part 2: Embed Metadata ═══")
        build_jar(force=args.rebuild_jar)
        run(["java", "-jar", JAR_PATH, pdf_path, elements_out, tagged_out])
        print(f"\n[pipeline] Tagged PDF: {tagged_out}")
    else:
        print("[pipeline] Skipping Part 2 (Java tagger).")

    print("\n[pipeline] Done.")


if __name__ == "__main__":
    main()