// Put the storebound skills and MCP server into an app or game project for one or more AI coding tools.
//   storebound install --agent claude|codex|cursor|copilot|windsurf|gemini|opencode[,...] [--dir .] [--dry]
//                      [--no-skills] [--no-mcp] [--command "bunx storebound"]
// Skills are copied to the tool's skills folder (our own skill folders are updated, nothing else is touched). The MCP
// entry "storebound" is added to the tool's config file; every other entry stays as it is. Re-running is safe.
// MCP command: `bunx storebound mcp` when the project has storebound in node_modules, else this toolchain's
// bin/storebound by absolute path (override with --command).
import { cpSync, existsSync, mkdirSync, readdirSync, readFileSync, writeFileSync } from 'node:fs';
import { homedir } from 'node:os';
import { dirname, join, resolve } from 'node:path';
import type { Args } from './lib/args';
import { AGENTS, type AgentId, isAgent, type McpCommand, mergeCodexToml, mergeJsonServer } from './lib/agents';
import { log, warn } from './lib/log';

const TOOLCHAIN = resolve(import.meta.dir, '..');

/** Every file of a folder, relative path -> content, for comparing skill folders. */
function snapshot(dir: string, base = dir, out = new Map<string, string>()): Map<string, string> {
  if (!existsSync(dir)) return out;
  for (const n of readdirSync(dir, { withFileTypes: true })) {
    const p = join(dir, n.name);
    if (n.isDirectory()) snapshot(p, base, out); else out.set(p.slice(base.length), readFileSync(p, 'utf8'));
  }
  return out;
}
const same = (a: Map<string, string>, b: Map<string, string>) => a.size === b.size && [...a].every(([k, v]) => b.get(k) === v);

export function mcpCommand(project: string, override?: string): McpCommand {
  if (override) { const [command, ...args] = override.split(/\s+/).filter(Boolean); return { command: command!, args: [...args, 'mcp'] }; }
  if (existsSync(join(project, 'node_modules', 'storebound', 'package.json'))) return { command: 'bunx', args: ['storebound', 'mcp'] };
  return { command: join(TOOLCHAIN, 'bin', 'storebound'), args: ['mcp'] };
}

export async function run(args: Args): Promise<void> {
  const agents = args.list('agent');
  if (!agents.length || !agents.every(isAgent)) throw new Error(`usage: install --agent ${Object.keys(AGENTS).join('|')}[,...] [--dir .] [--dry] [--no-skills] [--no-mcp]`);
  const project = resolve(args.str('dir', '.'));
  const dry = args.has('dry');
  const home = args.get('home') ?? homedir();
  const cmd = mcpCommand(project, args.get('command'));
  const skillsSrc = join(TOOLCHAIN, 'skills');
  const skills = readdirSync(skillsSrc).filter(n => existsSync(join(skillsSrc, n, 'SKILL.md'))).sort();
  const say = (m: string) => log('install', dry ? `${m} (dry)` : m);
  const doneDirs = new Set<string>();

  for (const id of agents as AgentId[]) {
    const a = AGENTS[id];
    log('install', `${a.label}`);
    if (!args.has('no-skills') && !doneDirs.has(a.skillsDir)) {
      doneDirs.add(a.skillsDir);
      let created = 0, updated = 0, kept = 0;
      for (const s of skills) {
        const from = join(skillsSrc, s);
        const to = join(project, a.skillsDir, s);
        const had = existsSync(to);
        if (had && same(snapshot(from), snapshot(to))) { kept++; continue; }
        if (!dry) { mkdirSync(dirname(to), { recursive: true }); cpSync(from, to, { recursive: true, force: true }); }
        if (had) updated++; else created++;
      }
      say(`skills -> ${a.skillsDir}: ${created} new, ${updated} updated, ${kept} up to date`);
    }
    if (!args.has('no-mcp')) {
      const rel = a.mcpFile({ home, xdg: process.env.XDG_CONFIG_HOME, exists: existsSync });
      const file = rel.startsWith('~/') ? join(home, rel.slice(2)) : rel.startsWith('/') ? rel : join(project, rel);
      const cur = existsSync(file) ? readFileSync(file, 'utf8') : null;
      try {
        const r = a.format === 'codex-toml' ? mergeCodexToml(cur, cmd) : mergeJsonServer(cur, a.format, cmd);
        if (!r.changed) log('install', `mcp ${rel}: up to date`);
        else {
          if (!dry) { mkdirSync(dirname(file), { recursive: true }); writeFileSync(file, r.text); }
          say(`mcp ${rel}: storebound -> ${cmd.command} ${cmd.args.join(' ')}`);
        }
      } catch (e) { warn('install', `mcp ${rel}: ${(e as Error).message}`); }
    }
    if (a.note) log('install', `  note: ${a.note}`);
  }
  log('install', 'restart the AI tool so it picks up the skills and the MCP server; credentials stay in env / .storebound/');
}