import importlib.util
import io
import tempfile
import unittest
from contextlib import redirect_stderr, redirect_stdout
from pathlib import Path


SCRIPT_PATH = (
    Path(__file__).resolve().parents[1]
    / "scripts"
    / "build_index.py"
)


def load_script():
    spec = importlib.util.spec_from_file_location(
        "tsl_codegen_function_index", SCRIPT_PATH
    )
    module = importlib.util.module_from_spec(spec)
    spec.loader.exec_module(module)
    return module


class FunctionIndexTest(unittest.TestCase):
    def setUp(self):
        self.temp_dir = tempfile.TemporaryDirectory()
        self.skill_dir = Path(self.temp_dir.name) / "tsl-api-reference"
        self.codegen_root = self.skill_dir / "references" / "codegen"
        self.data_dir = self.skill_dir / "data"
        leaf = self.codegen_root / "builtin" / "base" / "array.md"
        leaf.parent.mkdir(parents=True)
        leaf.write_text(
            "# Builtin - 基础 / 数组\n\n"
            "## `demo()`\n\n"
            "<!-- tags: 数组 列表 -->\n\n"
            "返回示例值。\n\n"
            "返回：integer\n",
            encoding="utf-8",
        )
        self.module = load_script()

    def tearDown(self):
        self.temp_dir.cleanup()

    def run_main(self, *args):
        stdout = io.StringIO()
        stderr = io.StringIO()
        with redirect_stdout(stdout), redirect_stderr(stderr):
            result = self.module.main(["--skill-dir", str(self.skill_dir), *args])
        return result, stdout.getvalue(), stderr.getvalue()

    def test_rebuild_writes_only_tsv(self):
        result, _, _ = self.run_main()

        self.assertEqual(0, result)
        self.assertTrue((self.data_dir / "function_index.tsv").is_file())
        self.assertEqual([], list(self.codegen_root.rglob("index.md")))

    def test_tags_and_summary_are_stored_separately(self):
        rows = self.module.build_rows(self.codegen_root)
        row = dict(zip(self.module.HEADER, rows[0]))

        self.assertEqual("数组 列表", row["tags"])
        self.assertEqual("返回示例值。", row["summary"])

    def test_check_does_not_require_index_pages(self):
        self.data_dir.mkdir(parents=True)
        rows = self.module.build_rows(self.codegen_root)
        (self.data_dir / "function_index.tsv").write_text(
            self.module.render_tsv(rows),
            encoding="utf-8",
            newline="\n",
        )

        result, stdout, _ = self.run_main("--check")

        self.assertEqual(0, result)
        self.assertIn("matches md tree", stdout)


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