"""Tests for Frontmatter parser — TOML frontmatter parsing and serialisation."""

from __future__ import annotations

from volumen.frontmatter import dump, parse


class TestParse:
    def test_parse_extracts_metadata_and_body(self) -> None:
        content = '+++\ntitle = "Hello"\ntags = ["a", "b"]\n+++\n\nBody text.\n'
        metadata, body = parse(content)
        assert metadata["title"] == "Hello"
        assert metadata["tags"] == ["a", "b"]
        assert body == "Body text.\n"

    def test_parse_without_frontmatter(self) -> None:
        metadata, body = parse("# Just markdown\n")
        assert metadata == {}
        assert body == "# Just markdown\n"

    def test_parse_without_closing_delimiter(self) -> None:
        content = '+++\ntitle = "x"\n\nbody'
        metadata, body = parse(content)
        assert metadata == {}
        assert body == content

    def test_parse_empty_frontmatter(self) -> None:
        content = "+++\n+++\n\nBody here.\n"
        metadata, body = parse(content)
        assert metadata == {}
        assert body == "Body here.\n"

    def test_parse_draft_false(self) -> None:
        content = '+++\ntitle = "X"\ndraft = false\n+++\n\nBody\n'
        metadata, body = parse(content)
        assert metadata["draft"] is False

    def test_parse_nested_tables(self) -> None:
        content = '+++\n[meta]\ntitle = "X"\n+++\n\nBody\n'
        metadata, body = parse(content)
        assert metadata["meta"]["title"] == "X"

    def test_parse_normalises_crlf(self) -> None:
        metadata, body = parse('+++\r\ntitle = "x"\r\n+++\r\n\r\nBody\r\n')
        assert metadata["title"] == "x"
        assert body == "Body\n"


class TestDump:
    def test_dump_produces_valid_frontmatter(self) -> None:
        result = dump({"title": "Hello", "tags": ["a"]}, "Body text.\n")
        assert result.startswith("+++\n")
        assert "+++\n\n" in result
        assert "Body text." in result

    def test_dump_empty_metadata(self) -> None:
        result = dump({}, "Just body.\n")
        assert "+++" in result
        assert "Just body." in result

    def test_round_trip(self) -> None:
        metadata = {"title": "Hello", "tags": ["intro"], "draft": False}
        dumped = dump(metadata, "Hello **world**.")
        parsed_meta, parsed_body = parse(dumped)
        assert parsed_meta == metadata
        assert parsed_body.strip() == "Hello **world**."

    def test_round_trip_with_empty_metadata(self) -> None:
        dumped = dump({}, "Just body.\n")
        parsed_meta, parsed_body = parse(dumped)
        assert parsed_meta == {}
        assert parsed_body.strip() == "Just body."

    def test_round_trip_preserves_dates(self) -> None:
        metadata = {"title": "X", "date": "2026-01-15"}
        dumped = dump(metadata, "Body\n")
        parsed_meta, _ = parse(dumped)
        assert parsed_meta["date"] == "2026-01-15"