import csv

from legex.analysis.report import build_report


def _write(path, header, rows):
    with path.open("w", encoding="utf-8", newline="") as f:
        w = csv.writer(f)
        w.writerow(header)
        w.writerows(rows)


def test_build_report_renders_sections_and_live_numbers(tmp_path) -> None:
    iaa = tmp_path / "iaa"
    iaa.mkdir()
    analysis = tmp_path

    _write(
        iaa / "pairwise_agreement.csv",
        ["annotator_a", "annotator_b", "country", "field", "n",
         "pct_exact", "pct_tolerant", "cohen_kappa"],
        [
            # categorical (fixed-vocab) -> kappa shown
            ["primary", "a1b2c3d4e5", "de", "plaintiff_no1_ISIC1_industry_category", "20", "0.5000", "0.5000", "0.4000"],
            # monetary -> kappa computed in CSV but suppressed in the report
            ["primary", "a1b2c3d4e5", "de", "court_cost_awarded_nominal", "20", "0.6000", "0.6500", "0.3000"],
            # free text -> percent only, kappa undefined
            ["primary", "a1b2c3d4e5", "de", "legal_subject_judgement", "20", "0.1000", "0.1000", ""],
        ],
    )
    # Reference-implementation output (scripts/alt_test_reference.py); an
    # empty string marks an untestable (country, field, variant) cell.
    _write(
        iaa / "alt_test_reference_gpt-5.4-mini.csv",
        ["candidate", "country", "field",
         "winning_rate", "advantage_probability", "passes",
         "winning_rate_nontrivial", "advantage_probability_nontrivial",
         "passes_nontrivial"],
        [
            ["gpt-5.4-mini", "de", "plaintiffs_all_count",
             "1.0", "0.95", "1", "1.0", "0.93", "1"],
            ["gpt-5.4-mini", "de", "dispute_value_nominal",
             "0.3333", "0.7", "0", "", "", ""],
        ],
    )
    _write(
        analysis / "per_column.csv",
        ["model", "column", "tp", "mismatch", "missed", "hallucinated", "tn",
         "accuracy", "recall_when_filled", "precision_when_emitted",
         "hallucination_rate", "miss_rate", "wrong_when_both_filled", "f1"],
        [["gpt-5.4-mini", "plaintiffs_all_count", "8", "1", "1", "0", "10",
          "0.9000", "0.8000", "0.8889", "0.0000", "0.1000", "0.1000", "0.8400"]],
    )

    md = build_report(iaa, analysis)

    for header in (
        "# Inter-Annotator Agreement",
        "## 1. Scope",
        "## 2. Human–human agreement",
        "## 3. Alternative-annotator test",
        "## 4. Headline extraction metrics",
        "Landis–Koch",
    ):
        assert header in md, header

    assert "### 2.1 By variable" in md
    assert "0.400" in md          # ISIC (categorical) kappa is shown
    assert "0.300" not in md      # monetary kappa is suppressed, not displayed
    assert "65.0%" in md          # monetary tolerant percent agreement
    assert "±" in md              # uncertainty (±1 SE) is shown
    assert "nominal" in md and "monetary" in md  # measurement-level labels
    assert "a1b2c3d4e5" in md           # by-pair table
    assert "80.0%" in md          # recall_when_filled rendered as percent (section 4)
    assert "1/2" in md            # alt-test pass count (1 of 2 testable cells)
    assert "1/1" in md            # non-trivial pass count (untestable cell excluded)
    assert "0.82" in md           # mean advantage probability rho
    assert "0.93" in md           # non-trivial mean rho (only the testable cell)
    # provenance: numbers come from the authors' reference implementation
    assert "nitaytech/AltTest" in md
    assert "alt_test_reference.py" in md
    # per-field grids for every headline metric
    assert "### 4.3 Precision by field" in md
    assert "### 4.4 Hallucination rate by field" in md
    assert "### 4.5 F1 by field" in md
    assert "0.840" in md          # F1 rendered as 0–1, not percent
    # the alt-test formula block is always rendered, CSVs or not
    assert "### 3.1 How ω and ρ are computed" in md
    assert "rho_j = (1/n_j)" in md              # advantage probability, with its >=
    assert "(1 - epsilon) / 2  =  0.4" in md    # the threshold epsilon actually buys
    # without the decomposition CSV, §3.4 degrades to a pointer
    assert "### 3.4 Substitutable vs. better" in md
    assert "alt_test_decomposition.py" in md


def test_alt_test_decomposition_separates_substitutable_from_better(tmp_path) -> None:
    """§3.4 reports the win/tie/loss counts rho hides, and rho with ties split."""
    iaa = tmp_path / "iaa"
    iaa.mkdir()
    _write(
        iaa / "alt_test_decomposition.csv",
        ["candidate", "country", "variant", "n_comparisons",
         "refs_disagree", "llm_better", "human_better",
         "tie", "tie_same", "tie_diff", "tie_at_1", "tie_at_half", "tie_at_0",
         "rho_alttest", "rho_tiebroken"],
        [
            # ties dominate: rho looks strong, but the human wins the decisive ones
            ["gpt-5.4-mini", "de", "all", "100",
             "36", "10", "14", "76", "57", "19", "38", "26", "12", "0.86", "0.48"],
            ["gpt-5.4-mini", "de", "nontrivial", "80",
             "30", "8", "8", "64", "48", "16", "32", "22", "10", "0.90", "0.50"],
        ],
    )

    md = build_report(iaa, tmp_path)

    assert "### 3.4 Substitutable vs. better" in md
    assert "76 (76%)" in md       # tie count and share
    assert "0.86" in md           # rho as the alt-test computes it
    assert "0.48" in md           # rho once ties are split -> chance
    # the tie bucket is itemised, both by score level and by same/different answer
    assert "57 (75%)" in md       # tie_same / tie
    assert "19 (25%)" in md       # tie_diff / tie -- ties that are real disagreements
    assert "38 (50%)" in md       # tie_at_1 / tie
    assert "26 (34%)" in md       # tie_at_half / tie -- only possible if refs conflict
    assert "12 (16%)" in md       # tie_at_0 / tie
    assert "631" not in md        # refs_disagree comes from the CSV, not hard-coded
    assert "36 of 100 comparisons (36%;" in md   # reference conflict rate
    # the reading: mostly real agreement, but the human takes the decisive calls
    assert "75% of those ties are real agreement" in md
    assert "the human wins 58% (14 vs 10)" in md       # 14 / (14 + 10) decisive
    assert "0.50." in md          # non-trivial rho (ties split) survives the filter