#!/usr/bin/env python3

"""Generate the standard overall accuracy report variants."""

from __future__ import annotations

import argparse
import datetime
import json
from pathlib import Path
from typing import Any

from measure_accuracy import (
    evaluate_rows,
    load_annotation_boxes,
    load_predicted_rows,
    parse_filter_names,
)
from measure_overall_accuracy import aggregate_reports, discover_pairs


REPORT_VARIANTS: tuple[dict[str, Any], ...] = (
    {
        "name": "no_filter",
        "filters": None,
        "filename": "overall_accuracy_report.json",
    },
    {
        "name": "non_armenian",
        "filters": "non-armenian",
        "filename": "overall_accuracy_filtered_non_armenian_report.json",
    },
    {
        "name": "graphics_headers_images_photos",
        "filters": "graphics,header,image,photo",
        "filename": "overall_accuracy_filtered_graphics_headers_images_photos_report.json",
    },
    {
        "name": "all_filters",
        "filters": "non-armenian,graphics,header,image,photo",
        "filename": "overall_accuracy_filtered_all_report.json",
    },
)


LoadedPage = tuple[str, Path, Path, Any, Any]


def parse_args() -> argparse.Namespace:
    """Parse command-line arguments."""
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument(
        "--data-dir",
        type=Path,
        default=Path(__file__).resolve().parent.parent / "box_grouping" / "data",
        help="Directory containing both prediction CSVs and annotation JSONs.",
    )
    parser.add_argument(
        "--predictions-dir",
        type=Path,
        dest="predictions_dir",
        help="Directory containing prediction CSVs (overrides --data-dir for CSVs).",
    )
    parser.add_argument(
        "--annotations-dir",
        type=Path,
        dest="annotations_dir",
        help="Directory containing annotation JSONs (overrides --data-dir for JSONs).",
    )
    parser.add_argument(
        "--output-dir",
        type=Path,
        default=Path(__file__).resolve().parent
        / "results"
        / datetime.datetime.now().isoformat(),
        help="Directory where the four aggregate report JSON files are written.",
    )
    parser.add_argument(
        "--coverage-threshold",
        type=float,
        default=1.0,
        help="Minimum fraction of words in a row that must fit a box for a full match.",
    )
    parser.add_argument(
        "--failure-example-count",
        type=int,
        default=5,
        help="Number of aggregate failure examples to keep per failure type.",
    )
    parser.add_argument(
        "--unit-level",
        dest="unit_level",
        choices=["word", "line"],
        default="word",
        help="Granularity of predicted rows: 'word' or 'line'.",
    )
    parser.add_argument(
        "--variant",
        choices=[v["name"] for v in REPORT_VARIANTS],
        default=None,
        help="Generate only this variant. Omit to generate all four.",
    )
    parser.add_argument(
        "--partial",
        action="store_true",
        help=(
            "Allow evaluation when prediction CSVs exist for only a subset of "
            "annotated pages. Missing pages are skipped with a warning."
        ),
    )
    return parser.parse_args()


def load_pages(
    predictions_dir: Path,
    annotations_dir: Path,
    *,
    partial: bool = False,
    unit_level: str = "word",
) -> list[LoadedPage]:
    """Load all matched CSV/JSON page pairs from the given directories."""
    return [
        (
            name,
            predictions_csv,
            annotations_json,
            load_predicted_rows(predictions_csv, unit_level=unit_level),
            load_annotation_boxes(annotations_json),
        )
        for name, predictions_csv, annotations_json in discover_pairs(
            predictions_dir, annotations_dir, partial=partial
        )
    ]


def build_report(
    *,
    loaded_pages: list[LoadedPage],
    filters: tuple[str, ...],
    coverage_threshold: float,
    failure_example_count: int,
    unit_level: str = "word",
) -> dict[str, Any]:
    """Run box grouping and evaluation for one filter variant."""
    page_reports: list[dict[str, Any]] = []
    for (
        name,
        predictions_csv,
        annotations_json,
        predicted_rows,
        annotation_boxes,
    ) in loaded_pages:
        report = evaluate_rows(
            predicted_rows=predicted_rows,
            annotation_boxes=annotation_boxes,
            coverage_threshold=coverage_threshold,
            failure_example_count=failure_example_count,
            hide_zero_cer_details=False,
            filters=filters,
            unit_level=unit_level,
        )
        page_reports.append(
            {
                "page_name": name,
                "predictions_csv": predictions_csv,
                "annotations_json": annotations_json,
                "report": report,
            }
        )

    return aggregate_reports(
        page_reports=page_reports,
        coverage_threshold=coverage_threshold,
        failure_example_count=failure_example_count,
        unit_level=unit_level,
    )


def main() -> None:
    """Run all report variants and write JSON files to the output directory."""
    args = parse_args()
    predictions_dir = (args.predictions_dir or args.data_dir).resolve()
    annotations_dir = (args.annotations_dir or args.data_dir).resolve()
    output_dir = args.output_dir.resolve()
    output_dir.mkdir(parents=True, exist_ok=True)
    loaded_pages = load_pages(
        predictions_dir, annotations_dir, partial=args.partial, unit_level=args.unit_level
    )

    variants = REPORT_VARIANTS
    if args.variant:
        variants = tuple(v for v in REPORT_VARIANTS if v["name"] == args.variant)

    for variant in variants:
        filters = parse_filter_names(variant["filters"])
        filter_label = ",".join(filters) if filters else "none"
        print(f"Generating {variant['name']} (filter={filter_label})...", flush=True)
        report = build_report(
            loaded_pages=loaded_pages,
            filters=filters,
            coverage_threshold=args.coverage_threshold,
            failure_example_count=args.failure_example_count,
            unit_level=args.unit_level,
        )

        variant_dir = output_dir / Path(variant["filename"]).stem
        variant_dir.mkdir(parents=True, exist_ok=True)

        pages = report.get("pages", [])
        for page in pages:
            page_path = variant_dir / f"{page['page_name']}.json"
            page_path.write_text(
                json.dumps(page, ensure_ascii=False, indent=2),
                encoding="utf-8",
            )

        summary_doc = {k: v for k, v in report.items() if k != "pages"}
        summary_path = variant_dir / "summary.json"
        summary_path.write_text(
            json.dumps(summary_doc, ensure_ascii=False, indent=2),
            encoding="utf-8",
        )

        summary = report["summary"]
        print(
            f"{variant['name']}: {variant_dir} "
            f"(filter={filter_label}, ocr_region_cer={summary['ocr_region_cer']}, "
            f"{len(pages)} page(s) + summary.json)",
            flush=True,
        )


if __name__ == "__main__":
    main()