import { readFile } from "node:fs/promises";
import { homedir } from "node:os";
import { join, resolve } from "node:path";

function getMcpConfigPaths(cwd) {
  return [
    join(homedir(), ".config", "mcp", "mcp.json"),
    join(homedir(), ".pi", "agent", "mcp.json"),
    resolve(cwd, ".mcp.json"),
    resolve(cwd, ".pi", "mcp.json"),
  ];
}

export async function isMcpServerConfigured(serverName, cwd) {
  return Boolean(await loadMcpServerConfig(serverName, cwd));
}

export async function loadMcpServerConfig(serverName, cwd) {
  let found = null;
  for (const configPath of getMcpConfigPaths(cwd)) {
    try {
      const raw = JSON.parse(await readFile(configPath, "utf8"));
      const servers = raw?.mcpServers ?? raw?.["mcp-servers"] ?? {};
      if (servers && typeof servers === "object" && !Array.isArray(servers) && servers[serverName]) {
        found = servers[serverName];
      }
    } catch {
      // Missing or invalid MCP configs are ignored here; pi-mcp-adapter owns user-facing setup diagnostics.
    }
  }
  return found;
}