from __future__ import annotations

from pathlib import Path

from docforge.model import Project


class MkDocsRenderer:
    """MkDocs source generator using mkdocstrings."""

    name = "mkdocs"

    def generate_sources(self, project: Project, out_dir: Path) -> None:
        """
        Generate Markdown files with mkdocstrings directives.

        Structure rules:
        - Each top-level package gets a directory
        - Modules become .md files
        - Packages (__init__) become index.md
        """
        for module in project.get_all_modules():
            self._write_module(project, module, out_dir)

    # -------------------------
    # Internal helpers
    # -------------------------

    def _write_module(self, project: Project, module, out_dir: Path) -> None:
        parts = module.path.split(".")

        # Root package directory
        pkg_dir = out_dir / parts[0]
        pkg_dir.mkdir(parents=True, exist_ok=True)

        # Package (__init__.py) → index.md
        if module.path == parts[0]:
            md_path = pkg_dir / "index.md"
            title = parts[0].replace("_", " ").title()
        else:
            # Submodule → <name>.md
            md_path = pkg_dir / f"{parts[-1]}.md"
            title = parts[-1].replace("_", " ").title()

        content = self._render_markdown(title, module.path)

        # Idempotent write
        if md_path.exists():
            if md_path.read_text(encoding="utf-8") == content:
                return

        md_path.write_text(content, encoding="utf-8")

    def _render_markdown(self, title: str, module_path: str) -> str:
        return (
            f"# {title}\n\n"
            f"::: {module_path}\n"
        )