import * as fs from "fs";
import * as path from "path";
import { GeneratedFile } from "./file-parser";

const TEMPLATE_DIR = path.join(process.cwd(), "templates", "nextjs-base");

function copyTemplate(destDir: string) {
  fs.mkdirSync(destDir, { recursive: true });
  fs.cpSync(TEMPLATE_DIR, destDir, { recursive: true });
}

// Framer Motion (and React hooks) only work in Client Components.
// If the model forgot the "use client" directive, add it automatically
// rather than relying on prompt compliance alone.
function needsClientDirective(content: string): boolean {
  return (
    /from\s+["']framer-motion["']/.test(content) ||
    /\buse(State|Effect|Ref|Context|Reducer|Callback|Memo)\b/.test(content)
  );
}

function ensureClientDirective(content: string): string {
  const trimmed = content.trimStart();
  if (trimmed.startsWith('"use client"') || trimmed.startsWith("'use client'")) {
    return content;
  }
  return needsClientDirective(content) ? '"use client";\n\n' + content : content;
}

export function writeProjectFiles(
  files: GeneratedFile[],
  projectSlug: string
): { projectDir: string; written: string[] } {
  const safeSlug = projectSlug.replace(/[^a-z0-9-]/gi, "-").toLowerCase().slice(0, 40);
  const projectDir = path.join(
    process.cwd(),
    "generated_projects",
    `${safeSlug}-${Date.now()}`
  );

  copyTemplate(projectDir);

  const written: string[] = [];

  for (const file of files) {
    const fullPath = path.join(projectDir, file.path);
    fs.mkdirSync(path.dirname(fullPath), { recursive: true });
    const content = file.path.endsWith(".tsx") ? ensureClientDirective(file.content) : file.content;
    fs.writeFileSync(fullPath, content, "utf-8");
    written.push(file.path);
  }

  return { projectDir, written };
}