import io
import sys
import json
import unittest
from src import index

class TestIndex(unittest.TestCase):
    def setUp(self):
        # Capture stdout
        self._stdout = sys.stdout
        sys.stdout = io.StringIO()

    def tearDown(self):
        sys.stdout = self._stdout

    def test_plain_output_contains_all_strings(self):
        # Run main without arguments
        index.main()
        output = sys.stdout.getvalue()
        # Check that all labels are present
        for label in index.LABELS:
            self.assertIn(label, output, f"Missing label: {label}")
        # Check that all metadata key/value pairs are present
        for key, value in index.METADATA.items():
            self.assertIn(f"{key}: {value}", output, f"Missing metadata: {key}")

    def test_json_output_structure(self):
        # Get JSON output via get_output
        json_str = index.get_output(json_output=True)
        data = json.loads(json_str)
        # Verify top-level keys
        self.assertIn("metadata", data)
        self.assertIn("labels", data)
        # Verify metadata content
        self.assertEqual(data["metadata"], index.METADATA)
        # Verify labels content
        self.assertEqual(data["labels"], index.LABELS)

    def test_main_returns_none(self):
        # main should return None
        result = index.main()
        self.assertIsNone(result)

    def test_output_is_not_empty(self):
        index.main()
        output = sys.stdout.getvalue()
        self.assertTrue(len(output.strip()) > 0)

    def test_get_output_plain(self):
        plain = index.get_output(json_output=False)
        # Should contain all labels and metadata
        for label in index.LABELS:
            self.assertIn(label, plain)
        for key, value in index.METADATA.items():
            self.assertIn(f"{key}: {value}", plain)

    def test_get_output_json(self):
        json_output = index.get_output(json_output=True)
        # Should be valid JSON
        try:
            data = json.loads(json_output)
        except json.JSONDecodeError as e:
            self.fail(f"JSON output is invalid: {e}")
        # Check that keys exist
        self.assertIn("metadata", data)
        self.assertIn("labels", data)

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