#!/usr/bin/env python3
from __future__ import annotations

import argparse
import json
from pathlib import Path

import table_ocr_backends


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(
        description=(
            "Run OCR on a PDF page, then overlay born-digital PDF cell bboxes "
            "and recovered bold/italic/underline formatting onto the returned table HTML."
        )
    )
    parser.add_argument("--pdf", required=True, help="Path to the source PDF.")
    parser.add_argument("--page", required=True, type=int, help="1-based PDF page number.")
    parser.add_argument(
        "--model-id",
        default=None,
        help="Optional OCR model id override. Defaults to the configured/default PDF page OCR model.",
    )
    parser.add_argument(
        "--input-html",
        default=None,
        help="Optional path to an existing OCR HTML fragment. When provided, the script skips OCR and only applies the PDF-native overlay.",
    )
    parser.add_argument(
        "--style-overlay-mode",
        default="auto",
        choices=["none", "attrs_only", "formatting_only", "auto", "aggressive"],
        help=(
            "Formatting overlay behavior. "
            "`formatting_only` preserves OCR text and only injects semantic bold/italic/underline tags. "
            "`auto` safely swaps in native styled cell HTML when the text match is strong. "
            "`aggressive` prefers native styled cell HTML whenever a cell matches."
        ),
    )
    parser.add_argument("--page-render-zoom", type=float, default=None, help="Optional PDF render zoom before OCR.")
    parser.add_argument("--output-html", default=None, help="Optional path to write the final annotated HTML.")
    parser.add_argument(
        "--output-raw-html",
        default=None,
        help=(
            "Optional path to write the original OCR HTML before PDF-native overlay. "
            "If omitted and --output-html is set, defaults to a sibling '*.raw.html' file."
        ),
    )
    parser.add_argument("--output-json", default=None, help="Optional path to write the full JSON payload.")
    return parser.parse_args()


def main() -> None:
    args = parse_args()
    if args.input_html:
        input_html_path = Path(args.input_html).resolve()
        input_html = input_html_path.read_text(encoding="utf-8")
        payload = table_ocr_backends.overlay_pdf_page_html_with_native_cells(
            input_html,
            pdf_path=args.pdf,
            page_number=max(1, int(args.page)),
            effective_model_id=args.model_id or "existing-html+pdf-overlay",
            style_overlay_mode=args.style_overlay_mode,
        )
    else:
        payload = table_ocr_backends.transcribe_pdf_page_to_payload(
            args.pdf,
            page_number=max(1, int(args.page)),
            model_id=args.model_id,
            page_render_zoom=args.page_render_zoom,
            overlay_pdf_cells=True,
            style_overlay_mode=args.style_overlay_mode,
        )

    output_html = str(payload.get("html") or "")
    raw_html = str(payload.get("raw_html") or output_html)
    output_html_path = Path(args.output_html).resolve() if args.output_html else None
    output_raw_html_path = None
    if args.output_raw_html:
        output_raw_html_path = Path(args.output_raw_html).resolve()
    elif output_html_path is not None:
        output_raw_html_path = output_html_path.with_name(f"{output_html_path.stem}.raw.html")

    if args.output_html:
        assert output_html_path is not None
        output_html_path.parent.mkdir(parents=True, exist_ok=True)
        output_html_path.write_text(output_html, encoding="utf-8")

    if output_raw_html_path is not None:
        output_raw_html_path.parent.mkdir(parents=True, exist_ok=True)
        output_raw_html_path.write_text(raw_html, encoding="utf-8")

    if args.output_json:
        output_json_path = Path(args.output_json).resolve()
        output_json_path.parent.mkdir(parents=True, exist_ok=True)
        output_json_path.write_text(json.dumps(payload, indent=2, sort_keys=True) + "\n", encoding="utf-8")

    if not args.output_html and not args.output_json:
        print(output_html)
        return

    summary = {
        "pdf": str(Path(args.pdf).resolve()),
        "page": int(args.page),
        "model_id": payload.get("effective_model_id"),
        "overlay_applied": bool(payload.get("overlay_applied")),
        "overlay_changed_html": output_html != raw_html,
        "style_overlay_mode": payload.get("style_overlay_mode"),
        "timings_ms": payload.get("timings_ms"),
        "output_html": str(output_html_path) if output_html_path is not None else None,
        "output_raw_html": str(output_raw_html_path) if output_raw_html_path is not None else None,
        "output_json": str(Path(args.output_json).resolve()) if args.output_json else None,
    }
    print(json.dumps(summary, indent=2, sort_keys=True))


if __name__ == "__main__":
    main()