from __future__ import annotations

from datetime import date
import io
from pathlib import Path
import tempfile
import unittest

from openpyxl import Workbook

from bank_importer.parser import (
    UnknownTemplateError,
    analyze_workbook,
    detect_header,
    parse_directory,
)


ROOT = Path(__file__).resolve().parents[1]
SAMPLES = ROOT / "流水模板"


class StatementParserTests(unittest.TestCase):
    @classmethod
    def setUpClass(cls) -> None:
        cls.batches = parse_directory(SAMPLES)
        cls.by_file = {batch.source_file.name: batch for batch in cls.batches}

    def test_all_current_bank_samples_are_recognized(self) -> None:
        expected = {
            "中信银行账户流水.xlsx": ("中信银行", 16, 4),
            "中国农业银行账户流水.xls": ("中国农业银行", 3, 4),
            "中国工商银行账户流水.xlsx": ("中国工商银行", 2, 5),
            "中国建设银行账户流水.xls": ("中国建设银行", 1, 1),
            "河南农商银行账户流水.xlsx": ("河南农商银行", 11, 1),
            "郑州银行账户流水.xls": ("郑州银行", 7, 5),
        }
        self.assertEqual(set(expected), set(self.by_file))
        for filename, (bank, header_row, transaction_count) in expected.items():
            with self.subTest(filename=filename):
                batch = self.by_file[filename]
                self.assertEqual(bank, batch.bank_name)
                self.assertEqual(header_row, batch.header_row)
                self.assertEqual(transaction_count, len(batch.transactions))

    def test_known_statement_periods_are_extracted(self) -> None:
        expected = {
            "中信银行账户流水.xlsx": (date(2026, 4, 26), date(2026, 5, 23)),
            "中国农业银行账户流水.xls": (date(2025, 11, 26), date(2025, 12, 27)),
            "河南农商银行账户流水.xlsx": (date(2026, 2, 24), date(2026, 3, 28)),
            "郑州银行账户流水.xls": (date(2026, 2, 24), date(2026, 3, 27)),
        }
        for filename, period in expected.items():
            with self.subTest(filename=filename):
                batch = self.by_file[filename]
                self.assertEqual(period, (batch.period_start, batch.period_end))

    def test_normalized_transactions_have_one_cash_direction(self) -> None:
        for batch in self.batches:
            for transaction in batch.transactions:
                with self.subTest(
                    filename=batch.source_file.name, row=transaction.source_row
                ):
                    self.assertNotEqual(transaction.income > 0, transaction.expense > 0)

    def test_current_samples_reconcile_by_running_balance(self) -> None:
        for batch in self.batches:
            with self.subTest(filename=batch.source_file.name):
                self.assertEqual((), batch.warnings)

    def test_column_order_does_not_affect_header_detection(self) -> None:
        header = (
            "余额",
            "对方单位名称",
            "贷方发生额",
            "交易时间",
            "本方账号",
            "借方发生额",
            "凭证号",
        )
        template, row_index, columns = detect_header((header,))
        self.assertEqual("icbc-history-detail-v1", template.template_id)
        self.assertEqual(0, row_index)
        self.assertEqual(3, columns["transaction_at"])

    def test_unknown_header_is_rejected(self) -> None:
        with self.assertRaises(UnknownTemplateError) as raised:
            detect_header((("日期", "金额", "备注"),))
        message = str(raised.exception)
        self.assertIn("未识别到受支持的银行表头", message)
        self.assertIn("第 1 行", message)
        self.assertIn("日期、金额、备注", message)


class SheetResultTests(unittest.TestCase):
    """Per-worksheet outcomes: parsed / exception / ignored with evidence."""

    def setUp(self) -> None:
        self.temp_dir = tempfile.TemporaryDirectory()
        self.addCleanup(self.temp_dir.cleanup)

    def _write(self, sheets) -> Path:
        workbook = Workbook()
        workbook.remove(workbook.active)
        for name, rows in sheets.items():
            worksheet = workbook.create_sheet(name)
            for row in rows:
                worksheet.append(row)
        path = Path(self.temp_dir.name) / "workbook.xlsx"
        workbook.save(path)
        return path

    def test_every_sheet_has_an_independent_result(self) -> None:
        path = self._write(
            {
                "正常": [
                    ["客户账号", "账户名称", "交易时间", "借方发生额（支取）", "贷方发生额（收入）", "余额", "对方账号"],
                    ["6228480000000000", "测试", "2026-01-05 10:00:00", "100.00", "", "99900.00", "1002003004"],
                ],
                "未知": [["日期", "金额", "备注"], ["2026-01-01", "100", "x"]],
                "空表": [],
            }
        )
        results = analyze_workbook(path)
        by_name = {result.sheet_name: result for result in results}
        self.assertEqual({"正常", "未知", "空表"}, set(by_name))
        self.assertEqual("parsed", by_name["正常"].outcome)
        self.assertIsNotNone(by_name["正常"].batch)
        self.assertEqual("exception", by_name["未知"].outcome)
        self.assertIn("未识别到受支持的银行表头", by_name["未知"].message)
        self.assertGreaterEqual(by_name["未知"].scanned_rows, 2)
        self.assertTrue(any("日期、金额、备注" in row for row in by_name["未知"].candidate_headers))
        self.assertEqual("ignored", by_name["空表"].outcome)
        self.assertEqual(0, by_name["空表"].scanned_rows)

    def test_single_cell_rows_are_candidate_evidence(self) -> None:
        path = self._write({"候选": [["只有一个单元格"], ["又一格"]]})
        (result,) = analyze_workbook(path)
        self.assertEqual("exception", result.outcome)
        self.assertEqual(2, result.scanned_rows)
        self.assertTrue(result.candidate_headers)
        self.assertIn("只有一个单元格", "；".join(result.candidate_headers))

    def test_messages_never_contain_stored_filename(self) -> None:
        path = self._write({"流水": [["日期", "金额", "备注"]]})
        (result,) = analyze_workbook(path)
        self.assertEqual("exception", result.outcome)
        self.assertNotIn(path.name, result.message)
        self.assertNotIn(str(path), result.message)


if __name__ == "__main__":
    unittest.main()