from pathlib import Path
from typing import Optional
import shutil
import jinja2
from dots_manager.config import Constants, Environment
from dots_manager.utils import is_some, parallelize


def is_template(path: Path) -> bool:
    return path.suffix == Constants.template_extension


def find_templates_under(destination: Path) -> list[Path]:
    return [
        t
        for t in destination.glob("**/*" + Constants.template_extension)
        if t.is_file() and is_template(t)
    ]


def render_template_to(
    template: Path, destination: Path, env: Environment
) -> Optional[Path]:
    env.logger.debug(f"rendering template {template} to {destination} ✧*ฺ")
    if not is_template(template):
        env.logger.error(f"{template} is not a valid template D:")
        return None

    jinja_env = jinja2.Environment(
        loader=jinja2.BaseLoader(),
        undefined=jinja2.StrictUndefined,
        trim_blocks=True,
        lstrip_blocks=True,
    )
    rendered = render(template, jinja_env, env)
    if not rendered:
        env.logger.error(f"failed to render template {template}")
        return None

    destination.write_text(rendered)
    destination.chmod(template.stat().st_mode)
    return destination


def render(
    source: Path, jinja_env: jinja2.Environment, env: Environment
) -> Optional[str]:
    try:
        env.logger.debug(f"rendering template {source} <_mood.happy>")
        return jinja_env.from_string(source.read_text()).render(**env.context)
    except Exception as e:
        env.logger.error(f"couldn’t render {source}: {e} <_mood.sad>")
        return None


def compile_dotfiles(source: Path, output: Path, env: Environment) -> bool:
    env.logger.info(f"compiling {source} to {output} <_mood.anxious>")
    output.mkdir(exist_ok=True, parents=True)
    shutil.copytree(source, output, dirs_exist_ok=True)

    tasks = parallelize(
        lambda template: is_some(
            render_template_to,
            template,
            template.with_suffix(""),
            env,
        )[0]
        and (template.unlink() is None),
        find_templates_under(output),
        env.logger,
    )
    return all(tasks)