/**
 * MCP install/uninstall commands.
 *
 * Manages the .mcp.json file at the plugin root (next to .claude-plugin/).
 * Claude Code discovers MCP servers from installed plugin directories,
 * not from the rig config dir.
 */

import { readFile, writeFile } from 'node:fs/promises';
import { join } from 'node:path';
import { fileURLToPath } from 'node:url';

const __dirname = fileURLToPath(new URL('.', import.meta.url));
const PROJECT_ROOT = join(__dirname, '..', '..');
const MCP_JSON_PATH = join(PROJECT_ROOT, '.mcp.json');
const SERVER_SCRIPT = '${CLAUDE_PLUGIN_ROOT}/src/mcp/server.ts';

const MCP_ENTRY_KEY = 'agent-awareness';

async function loadMcpJson(): Promise<Record<string, unknown>> {
  try {
    return JSON.parse(await readFile(MCP_JSON_PATH, 'utf8'));
  } catch {
    return {};
  }
}

async function saveMcpJson(data: Record<string, unknown>): Promise<void> {
  await writeFile(MCP_JSON_PATH, JSON.stringify(data, null, 2) + '\n', 'utf8');
}

export async function mcpInstall(): Promise<void> {
  const config = await loadMcpJson();

  if (config[MCP_ENTRY_KEY]) {
    console.log(`MCP server "${MCP_ENTRY_KEY}" already configured in ${MCP_JSON_PATH}`);
    return;
  }

  config[MCP_ENTRY_KEY] = {
    type: 'stdio',
    command: 'node',
    args: [SERVER_SCRIPT],
  };

  await saveMcpJson(config);
  console.log(`MCP server installed: ${MCP_JSON_PATH}`);
  console.log(`  command: node ${SERVER_SCRIPT}`);
  console.log(`  Restart Claude Code to pick up the new MCP server.`);
}

export async function mcpUninstall(): Promise<void> {
  const config = await loadMcpJson();

  if (!config[MCP_ENTRY_KEY]) {
    console.log(`MCP server "${MCP_ENTRY_KEY}" not found in ${MCP_JSON_PATH}`);
    return;
  }

  delete config[MCP_ENTRY_KEY];
  await saveMcpJson(config);
  console.log(`MCP server removed from ${MCP_JSON_PATH}`);
}

export async function mcpStatus(): Promise<void> {
  const config = await loadMcpJson();

  if (config[MCP_ENTRY_KEY]) {
    console.log(`MCP server: installed`);
    console.log(`  config: ${MCP_JSON_PATH}`);
    const entry = config[MCP_ENTRY_KEY] as Record<string, unknown>;
    console.log(`  command: ${entry.command} ${(entry.args as string[]).join(' ')}`);
  } else {
    console.log(`MCP server: not installed`);
    console.log(`  Run "agent-awareness mcp install" to set up`);
  }
}