import { copyFileSync, existsSync, mkdirSync } from "node:fs";
import { dirname, join, resolve } from "node:path";
import { fileURLToPath } from "node:url";
import { StdioServerTransport } from "@modelcontextprotocol/sdk/server/stdio.js";
import { NocoBaseAuthService } from "./auth-service.js";
import { loadConfig } from "./config.js";
import {
  createCredentialProvider,
  credentialsPath,
  loadStoredCredentials,
  NOCOBASE_API_BASE_URL,
  readHidden,
  saveCredentials,
  saveOAuthCredentials,
} from "./credentials.js";
import { CrmService } from "./crm-service.js";
import { NocoBaseClient } from "./nocobase-client.js";
import { loginWithBrowser } from "./oauth.js";
import { ProjectService } from "./project-service.js";
import { createServer } from "./tools.js";
import { VERSION } from "./version.js";

interface ParsedArgs {
  command: "serve" | "setup" | "doctor" | "client-config" | "help" | "version";
  config?: string;
  enableWrites: boolean;
  json: boolean;
  manualKey: boolean;
  noBrowser: boolean;
}

export async function runCli(argv = process.argv.slice(2)): Promise<void> {
  const args = parseArgs(argv);
  if (args.command === "help") {
    process.stdout.write(helpText());
    return;
  }
  if (args.command === "version") {
    process.stdout.write(`${VERSION}\n`);
    return;
  }
  if (args.command === "setup") {
    await setup(args);
    return;
  }
  const configPath = ensureConfig(args.config);
  if (args.command === "client-config") {
    printResult(clientConfig(configPath, args.enableWrites), args.json);
    return;
  }
  const runtime = createRuntime(configPath);
  if (args.command === "doctor") {
    await runtime.client.verifyCredentials();
    const health = await runtime.crm.crmHealth();
    printResult({ ok: true, credentials: "verified", health }, args.json);
    return;
  }
  const server = createServer({
    authService: new NocoBaseAuthService({ onCredentialsSaved: runtime.reloadCredentials }),
    crmService: runtime.crm,
    projectService: runtime.projects,
    readonly: !args.enableWrites,
    enableConfigTools: process.env.NOCOBASE_MCP_ENABLE_CONFIG_TOOLS?.trim() === "1",
  });
  const close = async (): Promise<void> => {
    await server.close();
    process.exit(0);
  };
  process.once("SIGINT", close);
  process.once("SIGTERM", close);
  await server.connect(new StdioServerTransport());
}

export function createRuntime(configPath: string): {
  client: NocoBaseClient;
  crm: CrmService;
  projects: ProjectService;
  reloadCredentials: () => void;
} {
  const config = loadConfig(configPath);
  const credentialProvider = createCredentialProvider();
  const client = new NocoBaseClient(credentialProvider, { dataSource: config.dataSource });
  return {
    client,
    crm: new CrmService(config, client),
    projects: new ProjectService(config.project, client),
    reloadCredentials: credentialProvider.reset,
  };
}

async function setup(args: ParsedArgs): Promise<void> {
  let authorizeKey: string;
  let authentication: "oauth-browser" | "personal-authorize-key-fallback";
  let configPath: string;
  if (args.manualKey) {
    if (!process.stdin.isTTY || !process.stderr.isTTY) {
      throw new Error("Manual Key setup requires a user-controlled local terminal; no files were changed");
    }
    process.stderr.write(
      `This MCP connects only to ${NOCOBASE_API_BASE_URL}.\n` +
        "Enter a revocable personal Authorize Key only in the hidden prompt below.\n" +
        "Do not paste the Key into Agent chat.\n",
    );
    configPath = ensureConfig(args.config);
    authorizeKey = (await readHidden("Personal NocoBase Authorize Key: ")).trim();
    if (!authorizeKey) throw new Error("Authorize Key must not be blank; no files were changed");
    authentication = "personal-authorize-key-fallback";
  } else {
    configPath = ensureConfig(args.config);
    process.stderr.write(
      `Signing in through ${NOCOBASE_API_BASE_URL} with NocoBase OAuth.\n` +
        "Your password and browser session stay inside NocoBase.\n",
    );
    const oauthCredentials = await loginWithBrowser({
      clientId: reusableOAuthClientId(),
      openBrowser: args.noBrowser ? async () => false : undefined,
      onAuthorization: ({ opened, url, userCode, expiresIn }) => {
        process.stderr.write(
          `${opened ? "Opened" : "Open"} the NocoBase authorization page in your browser:\n${url}\n` +
            `Confirmation code: ${userCode}\n` +
            `Complete sign-in within ${Math.ceil(expiresIn / 60)} minutes. Waiting for approval...\n`,
        );
      },
    });
    authorizeKey = oauthCredentials.accessToken;
    authentication = "oauth-browser";
    const verificationClient = new NocoBaseClient(() => ({
      apiBaseUrl: NOCOBASE_API_BASE_URL,
      authorizeKey,
    }));
    await verificationClient.verifyCredentials();
    saveOAuthCredentials(oauthCredentials);
    await printSetupResult(args, configPath, authentication);
    return;
  }
  const verificationClient = new NocoBaseClient(() => ({
    apiBaseUrl: NOCOBASE_API_BASE_URL,
    authorizeKey,
  }));
  await verificationClient.verifyCredentials();
  saveCredentials({ authorizeKey });
  await printSetupResult(args, configPath, authentication);
}

async function printSetupResult(
  args: ParsedArgs,
  configPath: string,
  authentication: "oauth-browser" | "personal-authorize-key-fallback",
): Promise<void> {
  const runtime = createRuntime(configPath);
  const health = await runtime.crm.crmHealth();
  printResult(
    {
      ok: true,
      apiBaseUrl: NOCOBASE_API_BASE_URL,
      authentication,
      credentialsPath: credentialsPath(),
      credentialExposure:
        authentication === "oauth-browser"
          ? "nocobase-browser-and-0600-local-file-only"
          : "private-tty-and-0600-local-file-only",
      configPath,
      mode: args.enableWrites ? "fixed-project-writes" : "read-only",
      clientConfig: clientConfig(configPath, args.enableWrites),
      health,
    },
    args.json,
  );
}

function reusableOAuthClientId(): string | undefined {
  const path = credentialsPath();
  if (!existsSync(path)) return undefined;
  const stored = loadStoredCredentials(path);
  return stored.type === "oauth" ? stored.clientId : undefined;
}

function ensureConfig(explicit?: string): string {
  const configured = explicit ?? process.env.NOCOBASE_MCP_CONFIG?.trim();
  if (configured) {
    const path = resolve(configured);
    if (!existsSync(path)) throw new Error(`Config file does not exist: ${path}`);
    return path;
  }
  const destination = join(dirname(credentialsPath()), "config.json");
  if (existsSync(destination)) return destination;
  mkdirSync(dirname(destination), { recursive: true, mode: 0o700 });
  const packageRoot = resolve(dirname(fileURLToPath(import.meta.url)), "..");
  const template = join(packageRoot, "config.example.json");
  if (!existsSync(template)) throw new Error(`Bundled config template is missing: ${template}`);
  copyFileSync(template, destination, 0);
  return destination;
}

export function clientConfig(configPath: string, enableWrites = false): Record<string, unknown> {
  const entrypoint = resolve(process.argv[1] ?? fileURLToPath(import.meta.url));
  return {
    mcpServers: {
      "nocobase-crm": {
        command: process.execPath,
        args: [entrypoint, "--config", configPath, ...(enableWrites ? ["--enable-writes"] : [])],
      },
    },
  };
}

function parseArgs(argv: string[]): ParsedArgs {
  const first = argv[0];
  let command: ParsedArgs["command"] = "serve";
  let index = 0;
  if (first && !first.startsWith("-")) {
    if (!["serve", "setup", "doctor", "client-config", "help", "version"].includes(first)) {
      throw new Error(`Unknown command: ${first}`);
    }
    command = first as ParsedArgs["command"];
    index = 1;
  }
  const parsed: ParsedArgs = {
    command,
    enableWrites: false,
    json: false,
    manualKey: false,
    noBrowser: false,
  };
  while (index < argv.length) {
    const flag = argv[index];
    if (flag === "--help" || flag === "-h") parsed.command = "help";
    else if (flag === "--version" || flag === "-v") parsed.command = "version";
    else if (flag === "--enable-writes") parsed.enableWrites = true;
    else if (flag === "--json") parsed.json = true;
    else if (flag === "--manual-key") parsed.manualKey = true;
    else if (flag === "--no-browser") parsed.noBrowser = true;
    else if (flag === "--config") {
      const value = argv[index + 1];
      if (!value || value.startsWith("-")) throw new Error(`${flag} requires a value`);
      parsed.config = value;
      index += 1;
    } else throw new Error(`Unknown option: ${flag}`);
    index += 1;
  }
  if (parsed.command !== "setup" && (parsed.manualKey || parsed.noBrowser)) {
    throw new Error("--manual-key and --no-browser are available only with setup");
  }
  if (parsed.manualKey && parsed.noBrowser)
    throw new Error("--manual-key cannot be combined with --no-browser");
  return parsed;
}

function printResult(value: unknown, json: boolean): void {
  process.stdout.write(`${JSON.stringify(value, null, json ? 0 : 2)}\n`);
}

function helpText(): string {
  return `NocoBase CRM MCP ${VERSION}

Usage:
  nocobase-crm-mcp setup [--config <path>] [--no-browser] [--manual-key] [--json]
  nocobase-crm-mcp [serve] [--config <path>] [--enable-writes]
  nocobase-crm-mcp doctor [--config <path>] [--json]
  nocobase-crm-mcp client-config [--config <path>] [--enable-writes] [--json]

The NocoBase API endpoint is fixed to ${NOCOBASE_API_BASE_URL}.
The setup command signs in through NocoBase OAuth in the user's browser.
Use --no-browser to print the authorization URL without opening it.
Use --manual-key only as a hidden local TTY fallback.
The stdio server can start before login; call nocobase_login to obtain a user-facing browser URL.
The default stdio server is read-only.
`;
}