#!/usr/bin/env python3
from typing import Any, Optional
from tomllib import load
from pathlib import Path
from dataclasses import dataclass, field
import questionary

TEMPLATES_DIR = Path("./_templates")

@dataclass(frozen=True)
class TemplateParameter:
    prompt: str
    default: Optional[Any] = None

@dataclass
class ProjectTemplate:
    name: str
    path: Path
    templates: list[str] = field(default_factory=list)
    parameters: dict[str, TemplateParameter] = field(default_factory=dict)



templates: dict[str, ProjectTemplate] = {}


for v in TEMPLATES_DIR.rglob("template.toml"):
    with v.open("rb") as fp:
        data = load(fp)
    tpl = ProjectTemplate(
        data.get('name', str(v.parent.relative_to(TEMPLATES_DIR))),
        v.parent,
        data.get('templates', []),
        {
            k: TemplateParameter(**v)
            for k, v in data.get('params', {}).items()
        }
    )
    templates[tpl.name] = tpl


project_name: Optional[str] = questionary.text("Project name").ask()
if not project_name:
    exit(1)

template: Optional[ProjectTemplate] = questionary.select("Template", [
    questionary.Choice(tpl.name, tpl) for tpl in templates.values()
]).ask()
if not template:
    exit(1)

parameters = questionary.prompt([
    {
        "type": "text",
        "name": k,
        "message": param.prompt,
        "default": param.default
    }
    for k, param in template.parameters.items()
])
if not parameters:
    exit(1)

project_dir = Path(project_name)
project_dir.mkdir(parents=True, exist_ok=True)

for base, dirs, files in template.path.walk():
    for dirname in dirs:
        (base / dirname).mkdir(exist_ok=True, parents=True)

    for filename in files:
        in_path = base / filename
        file_name = str(in_path.relative_to(template.path))
        out_path = project_dir / file_name
        if file_name == "template.toml":
            continue
        elif file_name in template.templates:
            print("TMPL", out_path)
            with in_path.open("r") as fp_in:
                with out_path.open("w") as fp_out:
                    for line in fp_in:
                        line = line.replace("__PROGNAME", project_name.split("/")[-1])
                        line = line.replace("__PROJECT", project_name)
                        for param in template.parameters:
                            line = line.replace(f"__{param}", parameters[param])
                        fp_out.write(line)
        else:
            print("COPY", out_path)
            with in_path.open("rb") as fp_in:
                with out_path.open("wb") as fp_out:
                    while (chunk := fp_in.read(32768)):
                        fp_out.write(chunk)