from __future__ import annotations

import json
from pathlib import Path

import pytest

from pdf2md.ir import (
    AssetRecord,
    BlockRecord,
    BlockType,
    DocumentRecord,
    PageRecord,
    WarningCode,
    WarningRecord,
    WarningSeverity,
)
from pdf2md.metadata import MetadataInputError, build_metadata, build_summary


def make_document(tmp_path: Path) -> DocumentRecord:
    page_zero = PageRecord(
        page_index=0,
        blocks=(
            BlockRecord(BlockType.HEADING, page_index=0),
            BlockRecord(BlockType.INLINE_FORMULA, page_index=0, confidence=0.98),
            BlockRecord(BlockType.DISPLAY_FORMULA, page_index=0, bbox=(1.0, 2.0, 3.0, 4.0)),
        ),
    )
    page_one = PageRecord(
        page_index=1,
        blocks=(
            BlockRecord(BlockType.PARAGRAPH, page_index=1),
            BlockRecord(BlockType.DISPLAY_FORMULA, page_index=1),
        ),
    )
    return DocumentRecord(
        source_pdf=tmp_path / "paper.pdf",
        pages=(page_zero, page_one),
        assets=(AssetRecord("paper.assets/figure.png", page_index=1),),
        warnings=(
            WarningRecord(WarningCode.READING_ORDER_UNCERTAIN, WarningSeverity.WARNING, "Check reading order.", page_index=1),
            WarningRecord(WarningCode.MATH_RENDER_FAILED, WarningSeverity.ERROR, "Math failed to render.", page_index=0),
        ),
    )


def build_test_metadata(tmp_path: Path) -> dict[str, object]:
    return build_metadata(
        document=make_document(tmp_path),
        source_sha256="0" * 64,
        created_at="2026-05-07T00:00:00Z",
        engine="MinerU",
        engine_version="3.1.0",
        engine_options={"strict_local": True},
    )


def test_metadata_has_required_top_level_fields(tmp_path: Path) -> None:
    metadata = build_test_metadata(tmp_path)

    assert set(metadata) == {
        "source_pdf",
        "source_sha256",
        "created_at",
        "engine",
        "engine_version",
        "engine_options",
        "pages",
        "assets",
        "warnings",
        "summary",
    }


def test_metadata_summary_counts_from_records(tmp_path: Path) -> None:
    metadata = build_test_metadata(tmp_path)

    assert metadata["summary"] == {
        "pages_processed": 2,
        "warning_count": 2,
        "asset_count": 1,
        "display_formula_count": 2,
        "inline_formula_count": 1,
        "math_render_error_count": 1,
    }


def test_warning_order_and_page_provenance_are_preserved(tmp_path: Path) -> None:
    metadata = build_test_metadata(tmp_path)

    warnings = metadata["warnings"]
    assert [warning["code"] for warning in warnings] == [
        "READING_ORDER_UNCERTAIN",
        "MATH_RENDER_FAILED",
    ]
    assert warnings[0]["page_index"] == 1
    assert warnings[1]["page_index"] == 0


def test_optional_bbox_and_confidence_are_preserved_only_when_present(tmp_path: Path) -> None:
    metadata = build_test_metadata(tmp_path)
    blocks = metadata["pages"][0]["blocks"]

    assert "confidence" not in blocks[0]
    assert blocks[1]["confidence"] == 0.98
    assert "bbox" not in blocks[1]
    assert blocks[2]["bbox"] == [1.0, 2.0, 3.0, 4.0]


def test_metadata_is_json_serializable(tmp_path: Path) -> None:
    json.dumps(build_test_metadata(tmp_path))


@pytest.mark.parametrize(
    ("field_name", "kwargs"),
    [
        ("document", {"document": None}),
        ("source_sha256", {"source_sha256": ""}),
        ("created_at", {"created_at": ""}),
        ("engine", {"engine": ""}),
        ("engine_version", {"engine_version": ""}),
    ],
)
def test_metadata_requires_core_inputs(tmp_path: Path, field_name: str, kwargs: dict[str, object]) -> None:
    values: dict[str, object] = {
        "document": make_document(tmp_path),
        "source_sha256": "0" * 64,
        "created_at": "2026-05-07T00:00:00Z",
        "engine": "MinerU",
        "engine_version": "3.1.0",
    }
    values.update(kwargs)

    with pytest.raises(MetadataInputError, match=field_name):
        build_metadata(**values)


def test_engine_options_must_be_json_serializable(tmp_path: Path) -> None:
    with pytest.raises(MetadataInputError, match="JSON serializable"):
        build_metadata(
            document=make_document(tmp_path),
            source_sha256="0" * 64,
            created_at="2026-05-07T00:00:00Z",
            engine="MinerU",
            engine_version="3.1.0",
            engine_options={"path": tmp_path},
        )


def test_formula_counts_come_from_block_types_not_markdown_text(tmp_path: Path) -> None:
    document = DocumentRecord(
        source_pdf=tmp_path / "paper.pdf",
        pages=(PageRecord(page_index=0, blocks=(BlockRecord(BlockType.PARAGRAPH), BlockRecord(BlockType.UNKNOWN))),),
    )

    summary = build_summary(document)

    assert summary["inline_formula_count"] == 0
    assert summary["display_formula_count"] == 0


def test_info_math_render_warning_is_not_counted_as_render_error(tmp_path: Path) -> None:
    document = DocumentRecord(
        source_pdf=tmp_path / "paper.pdf",
        pages=(PageRecord(page_index=0, blocks=(BlockRecord(BlockType.INLINE_FORMULA),)),),
        warnings=(WarningRecord(WarningCode.MATH_RENDER_FAILED, WarningSeverity.INFO, "Checker unavailable."),),
    )

    summary = build_summary(document)

    assert summary["warning_count"] == 1
    assert summary["math_render_error_count"] == 0