"""DataGate 机制化测试（T14，OV5）。

OV5 裁定：DataGate 是原则非机制，1000 行 Excel 上下文爆炸
→ 机制化：规模保护（超阈值无 selector 拒绝全量）+ token 预算控制 + 子集加载。
"""

from __future__ import annotations

import pytest

from genesis.data_models import CellValue, ExcelTable, Provenance, SheetType
from genesis.orchestrator.datagate import (
    DataGate,
    DataGateError,
    DataSelector,
    DataGateResult,
)


def _table(name: str, n_rows: int) -> ExcelTable:
    rows: list[dict[str, CellValue]] = []
    for i in range(n_rows):
        rows.append({
            "ID": CellValue(
                value=f"{name}-{i}",
                provenance=Provenance(file_name="要件定義.xlsx", sheet_name=name, row=i + 2, column="A", column_header="ID"),
            )
        })
    return ExcelTable(
        name=name,
        detected_type=SheetType.FUNCTION,
        extraction_method="structured",
        headers=["ID"],
        rows=rows,
    )


# ---------- 子集加载 ----------

def test_load_returns_selector_subset():
    gate = DataGate()
    source = _source_with_tables(["機能一覧", "画面一覧"], rows_each=5)

    result = gate.load(source, DataSelector(table_ids=["画面一覧"]))

    assert isinstance(result, DataGateResult)
    assert result.loaded_tables == ["画面一覧"]
    assert result.loaded_rows == 5


# ---------- 规模保护（OV5 核心：1000 行 Excel 防上下文爆炸） ----------

def test_load_rejects_huge_source_without_selector():
    gate = DataGate(max_total_rows=500)
    source = _source_with_tables(["機能一覧"], rows_each=1000)

    with pytest.raises(DataGateError, match="selector"):
        gate.load(source)


def test_load_allows_small_source_without_selector():
    gate = DataGate(max_total_rows=500)
    source = _source_with_tables(["機能一覧"], rows_each=10)

    result = gate.load(source)

    assert result.loaded_rows == 10


def test_huge_source_with_selector_is_allowed():
    """1000 行 Excel + selector 限定单表 → 不触发全量防护。"""
    gate = DataGate(max_total_rows=500)
    source = _source_with_tables(["機能一覧", "画面一覧", "帳票一覧"], rows_each=1000)

    result = gate.load(source, DataSelector(table_ids=["画面一覧"]))

    assert result.loaded_tables == ["画面一覧"]
    assert result.loaded_rows == 1000


# ---------- token 预算控制 ----------

def test_token_budget_rejects_huge_load():
    gate = DataGate(max_total_tokens=100)
    source = _source_with_tables(["機能一覧"], rows_each=200)

    with pytest.raises(DataGateError, match="token"):
        gate.load(source, DataSelector(table_ids=["機能一覧"]))


def test_token_budget_ok_within_limit():
    gate = DataGate(max_total_tokens=10_000)
    source = _source_with_tables(["機能一覧"], rows_each=20)

    result = gate.load(source, DataSelector(table_ids=["機能一覧"]))

    assert result.token_estimate <= 10_000


# ---------- 未知表容错 ----------

def test_unknown_table_id_returns_empty():
    gate = DataGate()
    source = _source_with_tables(["機能一覧"], rows_each=5)

    result = gate.load(source, DataSelector(table_ids=["不存在"]))

    assert result.loaded_tables == []
    assert result.loaded_rows == 0


def test_empty_selector_equals_no_selector():
    """selector 未指定任何表 → 等同无 selector，触发规模保护。"""
    gate = DataGate(max_total_rows=10)
    source = _source_with_tables(["機能一覧"], rows_each=100)

    with pytest.raises(DataGateError, match="selector"):
        gate.load(source, DataSelector())


def _source_with_tables(names: list[str], rows_each: int):
    from genesis.data_models import (
        ExistingSystemInfo,
        ImageAnalysis,
        ParsedTemplate,
        RuleDocument,
        StructuredSource,
    )

    return StructuredSource(
        tables=[_table(n, rows_each) for n in names],
        template=ParsedTemplate(file_name="template.docx", sections=[], placeholders={}, styles={}),
        rule_docs=[],
        image_analyses=[],
        existing_system=None,
        comments=[],
    )