#!/usr/bin/env runts -- --allow-env --allow-run

import {
    existsPath,
    joinPath,
    log,
    readFileToString,
    resolveFilename,
} from "https://global.hatter.ink/script/get/@12/deno-commons-mod.ts";

const PYTHON_CONFIG_FILE = "~/.config/python-config.json";
const PYTHON_VENV_DEFAULT_BASE_DIR = "~/.venv/";

interface PythonConfig {
    default_version?: string;
    default_profile?: string;
    python_venv_base_path?: string;
    versions: Map<string, PythonVersion>;
    profiles?: Map<string, PythonVenv>;
}

interface PythonVersion {
    version: string;
    path: string;
    comment?: string;
}

interface PythonVenv {
    version: string;
    path: string;
    comment?: string;
}

async function loadPythonConfig(): Promise<PythonConfig> {
    const pythonConfigFile = resolveFilename(PYTHON_CONFIG_FILE);
    const pythonConfigJson = await readFileToString(pythonConfigFile);
    if (!pythonConfigJson === null) {
        throw `Could not read python config file: ${pythonConfigFile}`;
    }
    return JSON.parse(pythonConfigJson) as PythonConfig;
}

async function newVirtualEnv(pythonVersion: string | null, pythonVenv: string) {
    const pythonConfig = await loadPythonConfig();
    const selectedPythonVersion = pythonVersion ||
        pythonConfig.default_version || null;
    if (!selectedPythonVersion) {
        throw `No Python version assigned.`;
    }
    if (!selectedPythonVersion) {
        throw `No Python venv assigned.`;
    }
    const pythonVersionProfile = pythonConfig.versions[pythonVersion];
    if (!pythonVersionProfile) {
        throw `Python version: ${pythonVersion} not found`;
    }
    log.success(`Found Python version: ${pythonVersion}`);
    const pythonVenvProfile = pythonConfig.profiles[pythonVenv];
    if (pythonVenvProfile) {
        throw `Python venv already exists: ${pythonVenv}`;
    }
    const pythonVenvBaseDir = resolveFilename(
        pythonConfig.python_venv_base_path || PYTHON_VENV_DEFAULT_BASE_DIR,
    );
    if (!existsPath(pythonVenvBaseDir)) {
        log.info(`Make python venv base dir: ${pythonVenvBaseDir}`);
        Deno.mkdirSync(pythonVenvBaseDir);
    }
    const pythonVenvDir = joinPath(pythonVenvBaseDir, pythonVenv);
    if (existsPath(pythonVenvDir)) {
        throw `Python venv: ${pythonVenvDir} already exists`;
    }

    // python3 -m venv myenv
    const python3Cmd = joinPath(pythonVersionProfile.path, "bin", "python3");
    const pythonVenvArgs = ["-m", "vent", pythonVenvDir];
}

async function main() {
    // TODO ...
}
await main();

// TODO ...