import { existsSync, readFileSync } from "node:fs";
import { join } from "node:path";
import type { ProjectConfig } from "./types.js";

export function detectProject(rootPath: string): ProjectConfig {
	const config: ProjectConfig = {};

	// Node.js detection
	const packageJsonPath = join(rootPath, "package.json");
	if (existsSync(packageJsonPath)) {
		try {
			const pkg = JSON.parse(readFileSync(packageJsonPath, "utf8")) as Record<
				string,
				unknown
			>;
			if (pkg.name) config.name = String(pkg.name);
			config.language = "TypeScript";
			if (pkg.workspaces) config.packageManager = "npm";
			if (existsSync(join(rootPath, "pnpm-lock.yaml")))
				config.packageManager = "pnpm";
			if (existsSync(join(rootPath, "yarn.lock")))
				config.packageManager = "yarn";
			if (existsSync(join(rootPath, "bun.lockb")))
				config.packageManager = "bun";
		} catch {
			/* ignore */
		}
	}

	// Python detection
	if (
		existsSync(join(rootPath, "pyproject.toml")) ||
		existsSync(join(rootPath, "setup.py"))
	) {
		config.language = "Python";
		config.packageManager = "pip";
	}

	// Go detection
	if (existsSync(join(rootPath, "go.mod"))) {
		config.language = "Go";
		config.packageManager = "go";
	}

	// Rust detection
	if (existsSync(join(rootPath, "Cargo.toml"))) {
		config.language = "Rust";
		config.packageManager = "cargo";
	}

	// Frappe/ERPNext detection
	if (
		existsSync(join(rootPath, "sites")) ||
		existsSync(join(rootPath, "apps")) ||
		existsSync(join(rootPath, "hooks.py"))
	) {
		config.framework = "frappe";
	}

	// Next.js detection
	if (
		existsSync(join(rootPath, "next.config.js")) ||
		existsSync(join(rootPath, "next.config.ts"))
	) {
		config.framework = "nextjs";
	}

	// Vite detection
	if (
		existsSync(join(rootPath, "vite.config.js")) ||
		existsSync(join(rootPath, "vite.config.ts"))
	) {
		config.buildTool = "vite";
	}

	return config;
}