import json
from pathlib import Path
import subprocess
import sys
import unittest
from check import MAX_BYTES, MAX_FIELD_CHARACTERS, audit


class Cases(unittest.TestCase):
    def test_quoted_delimiter_and_doubled_quote(self):
        self.assertTrue(audit(b'id,note\n001,"a,b"\n002,"a""b"\n')["ok"])

    def test_multiline_record_and_physical_error_span(self):
        result = audit(b'id,note\r\n001,"line1\r\nline2",extra\r\n')
        self.assertEqual(result["errors"][0], {"code": "column_count", "record": 2, "physical_line_start": 2, "physical_line_end": 3, "expected": 2, "actual": 3})

    def test_duplicate_and_empty_header(self):
        self.assertEqual(audit(b'id,id\n001,002\n')["errors"][0]["code"], "duplicate_header")
        self.assertEqual(audit(b'id, \n001,x\n')["errors"][0]["code"], "empty_header")

    def test_missing_and_extra_fields(self):
        result = audit(b'a,b\n1\n1,2,3\n')
        self.assertEqual([error["actual"] for error in result["errors"]], [1, 3])

    def test_blank_record_differs_from_quoted_empty_field(self):
        self.assertFalse(audit(b'a\n\n')["ok"])
        self.assertTrue(audit(b'a\n""\n')["ok"])

    def test_trailing_empty_field(self):
        self.assertTrue(audit(b'a,b\n001,\n')["ok"])

    def test_explicit_delimiter_and_no_header(self):
        result = audit(b'001\t002\n003\t004\n', '\t', False)
        self.assertEqual((result["ok"], result["columns"], result["data_rows"], result["header"]), (True, 2, 2, None))

    def test_dialect_is_not_guessed(self):
        result = audit(b'a;b\n1;2\n')
        self.assertEqual(result["columns"], 1)
        self.assertTrue(result["ok"])

    def test_no_type_inference_or_formula_execution(self):
        result = audit(b'001,=SUM(A1:A2)\n0002,formula\n')
        self.assertEqual(result["header"], ['001', '=SUM(A1:A2)'])

    def test_unterminated_quote(self):
        self.assertEqual(audit(b'a,b\n1,"unterminated')["errors"][0]["code"], "csv_parse_error")

    def test_not_a_complete_rfc_validator(self):
        self.assertTrue(audit(b'a,b\n1,ab"cd\n')["ok"])

    def test_utf8_bom_and_invalid_utf8(self):
        self.assertEqual(audit(b'\xef\xbb\xbfa,b\n1,2\n')["header"], ['a', 'b'])
        self.assertEqual(audit(b'a\n\xff\n')["errors"][0]["code"], "invalid_utf8")

    def test_resource_limits_and_empty_file(self):
        self.assertEqual(audit(b'a' * (MAX_BYTES + 1))["errors"][0]["code"], "input_too_large")
        self.assertEqual(audit(b'a\n' + b'x' * (MAX_FIELD_CHARACTERS + 1))["errors"][0]["code"], "field_too_large")
        self.assertEqual(audit(b'')["errors"][0]["code"], "empty_input")

    def test_bounded_diagnostics(self):
        result = audit(b'a,b\n' + b'1\n' * 120)
        self.assertEqual((result["error_count"], len(result["errors"]), result["errors_truncated"]), (120, 100, True))

    def test_cli_error_exit(self):
        result = subprocess.run([sys.executable, str(Path(__file__).with_name("check.py"))], input=b'id,id\n1,2\n', capture_output=True)
        self.assertEqual(result.returncode, 1)
        self.assertFalse(json.loads(result.stdout)["ok"])


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