import os
import stat
from pathlib import Path
from typing import Optional

import click

from local_commit_message_generator.config import Config
from local_commit_message_generator.templates import TemplateManager


class HookManager:
    def __init__(self, repo_path: Optional[str] = None):
        self.repo_path = Path(repo_path) if repo_path else Path.cwd()
        self.hooks_dir = self.repo_path / ".git" / "hooks"
        self.hook_file = self.hooks_dir / "prepare-commit-msg"

    def check_git_repo(self) -> bool:
        git_dir = self.repo_path / ".git"
        return git_dir.exists() and git_dir.is_dir()

    def install_hook(self, config: Config) -> bool:
        if not self.check_git_repo():
            click.echo("Error: Not a git repository", err=True)
            return False

        self.hooks_dir.mkdir(parents=True, exist_ok=True)

        existing_content = None
        if self.hook_file.exists():
            existing_content = self.hook_file.read_text()
            click.echo(f"Backing up existing hook to {self.hook_file}.backup")
            backup_file = self.hook_file.with_suffix(".backup")
            backup_file.write_text(existing_content)

        hook_content = self._generate_hook_script(config)
        self.hook_file.write_text(hook_content)
        os.chmod(self.hook_file, stat.S_IRWXU)

        click.echo(f"Hook installed at {self.hook_file}")
        return True

    def uninstall_hook(self) -> bool:
        if not self.check_git_repo():
            click.echo("Error: Not a git repository", err=True)
            return False

        if not self.hook_file.exists():
            click.echo("Hook not installed")
            return False

        backup_file = self.hook_file.with_suffix(".backup")
        if backup_file.exists():
            backup_file.replace(self.hook_file)
            click.echo("Restored backup hook")
        else:
            self.hook_file.unlink()
            click.echo("Removed hook")

        return True

    def _generate_hook_script(self, config: Config) -> str:
        template_manager = TemplateManager()
        template = template_manager.get_template("hook")

        return template.format(
            script_path=os.path.abspath(__file__),
            module_name="local_commit_message_generator"
        )