import { cancel, confirm, intro, isCancel, log, note, outro, spinner } from "@clack/prompts";
import { Command, Option } from "commander";
import { writeFileSync } from "node:fs";
import path from "node:path";
import { loadPersistedConfig, type PersistedConfig } from "@getpaseo/server";
import {
  resolveLocalPaseoHome,
  resolveLocalDaemonState,
  resolveTcpHostFromListen,
  startLocalDaemonDetached,
  tailDaemonLog,
  type DaemonStartOptions,
} from "./daemon/local-daemon.js";
import { tryConnectToDaemon } from "../utils/client.js";
import { formatPairingInstructions } from "../output/pairing.js";
import {
  confirmRelayPairing,
  printDirectConnectionGuidance,
  resolveLocalPairingOffer,
} from "./daemon/pair.js";

interface OnboardOptions extends DaemonStartOptions {
  timeout?: string;
  voice?: "ask" | "enable" | "disable";
}

type RawOnboardOptions = OnboardOptions & {
  allowedHosts?: string;
};

type OnboardPersistedConfig = PersistedConfig & {
  features?: PersistedConfig["features"] & {
    dictation?: PersistedConfig["features"] extends { dictation?: infer T }
      ? T & { enabled?: boolean }
      : { enabled?: boolean };
    voiceMode?: PersistedConfig["features"] extends { voiceMode?: infer T }
      ? T & { enabled?: boolean }
      : { enabled?: boolean };
  };
};

const DEFAULT_READY_TIMEOUT_MS = 10 * 60 * 1000;
const READY_PROBE_TIMEOUT_MS = 1200;

class OnboardCancelledError extends Error {}

const plainNoteFormat = (line: string): string => line;

function renderNote(message: string, title: string): void {
  note(message, title, { format: plainNoteFormat });
}

function sleep(ms: number): Promise<void> {
  return new Promise((resolve) => {
    setTimeout(resolve, ms);
  });
}

function parseTimeoutMs(raw: string | undefined): number {
  if (!raw || raw.trim().length === 0) {
    return DEFAULT_READY_TIMEOUT_MS;
  }

  const seconds = Number(raw);
  if (!Number.isFinite(seconds) || seconds <= 0) {
    throw new Error(`Invalid timeout value: ${raw}`);
  }

  return Math.ceil(seconds * 1000);
}

function savePersistedConfig(paseoHome: string, config: OnboardPersistedConfig): void {
  const configPath = path.join(paseoHome, "config.json");
  writeFileSync(configPath, `${JSON.stringify(config, null, 2)}\n`);
}

function applyVoiceSelection(
  config: OnboardPersistedConfig,
  enabled: boolean,
): OnboardPersistedConfig {
  return {
    ...config,
    features: {
      ...config.features,
      dictation: {
        ...config.features?.dictation,
        enabled,
      },
      voiceMode: {
        ...config.features?.voiceMode,
        enabled,
      },
    },
  };
}

function resolvePersistedVoiceSelection(config: OnboardPersistedConfig): boolean | null {
  const voiceModeEnabled = config.features?.voiceMode?.enabled;
  if (typeof voiceModeEnabled === "boolean") {
    return voiceModeEnabled;
  }

  const dictationEnabled = config.features?.dictation?.enabled;
  if (typeof dictationEnabled === "boolean") {
    return dictationEnabled;
  }

  return null;
}

async function resolveVoiceSelection(mode: OnboardOptions["voice"]): Promise<boolean> {
  if (mode === "enable") {
    return true;
  }
  if (mode === "disable") {
    return false;
  }

  if (!process.stdin.isTTY || !process.stdout.isTTY) {
    log.message("Non-interactive terminal detected; voice setup defaults to disabled.");
    return false;
  }

  const answer = await confirm({
    message: "Enable voice features? (downloads local STT/TTS models in background)",
    active: "Yes",
    inactive: "No",
    initialValue: false,
  });

  if (isCancel(answer)) {
    throw new OnboardCancelledError("Onboarding cancelled by user.");
  }

  return answer;
}

interface DownloadProgress {
  modelId: string | null;
  pct: number | null;
}

function parseDownloadProgress(logTail: string): DownloadProgress | null {
  const lines = logTail.split("\n").filter(Boolean);

  for (let index = lines.length - 1; index >= 0; index -= 1) {
    const line = lines[index];
    if (!line || !line.includes("Downloading model artifact")) {
      continue;
    }

    const pctMatch = line.match(/"pct"\s*:\s*(\d{1,3})|\bpct[=:]\s*(\d{1,3})/);
    const modelMatch = line.match(/"modelId"\s*:\s*"([^"]+)"|\bmodelId[=:]\s*"?([^\s",}]+)/);

    return {
      modelId: modelMatch?.[1] ?? modelMatch?.[2] ?? null,
      pct: pctMatch ? Number(pctMatch[1] ?? pctMatch[2]) : null,
    };
  }

  return null;
}

function renderProgressLine(progress: DownloadProgress): string {
  const modelSuffix = progress.modelId ? ` (${progress.modelId})` : "";
  if (progress.pct === null) {
    return `Downloading speech model${modelSuffix}...`;
  }
  return `Downloading speech model${modelSuffix}: ${progress.pct}%`;
}

type ProbeResult = { kind: "ready"; listen: string; host: string | null } | { kind: "pending" };

async function probeDaemonReady(home: string, timeoutMs: number): Promise<ProbeResult> {
  const state = resolveLocalDaemonState({ home });
  const host = resolveTcpHostFromListen(state.listen);
  const deadline = Date.now() + timeoutMs;
  const remainingTimeoutMs = () => Math.max(1, deadline - Date.now());

  if (state.running && host) {
    const client = await tryConnectToDaemon({
      host,
      timeout: Math.min(remainingTimeoutMs(), READY_PROBE_TIMEOUT_MS),
    });
    if (client) {
      try {
        await client.fetchAgents({
          timeout: Math.min(remainingTimeoutMs(), READY_PROBE_TIMEOUT_MS),
        });
        return { kind: "ready", listen: state.listen, host };
      } catch {
        // Daemon process is alive but not API-ready yet.
      } finally {
        await client.close().catch(() => {});
      }
    }
  } else if (state.running && !host) {
    return { kind: "ready", listen: state.listen, host: null };
  }

  return { kind: "pending" };
}

interface ProgressState {
  lastStatus: string;
  lastPrintedAt: number;
}

function announceProgress(
  home: string,
  state: ProgressState,
  onStatus: ((message: string) => void) | undefined,
): ProgressState {
  const progress = parseDownloadProgress(tailDaemonLog(home, 120) ?? "");
  const progressLine = progress ? renderProgressLine(progress) : null;
  const statusMessage = progressLine ?? "Waiting for daemon to become ready...";

  if (statusMessage !== state.lastStatus) {
    onStatus?.(statusMessage);
    return { lastStatus: statusMessage, lastPrintedAt: Date.now() };
  }
  if (!onStatus && Date.now() - state.lastPrintedAt >= 3000) {
    console.log(statusMessage);
    return { lastStatus: state.lastStatus, lastPrintedAt: Date.now() };
  }
  return state;
}

async function waitForDaemonReady(args: {
  home: string;
  timeoutMs: number;
  onStatus?: (message: string) => void;
}): Promise<{ listen: string; host: string | null }> {
  const deadline = Date.now() + args.timeoutMs;
  const createTimeoutError = () => {
    const recentLogs = tailDaemonLog(args.home, 60);
    return new Error(
      [
        `Timed out after ${Math.ceil(args.timeoutMs / 1000)}s waiting for daemon readiness.`,
        recentLogs ? `Recent daemon logs:\n${recentLogs}` : null,
      ]
        .filter(Boolean)
        .join("\n\n"),
    );
  };

  async function poll(state: ProgressState): Promise<{ listen: string; host: string | null }> {
    if (Date.now() >= deadline) {
      throw createTimeoutError();
    }
    const probe = await probeDaemonReady(args.home, Math.max(1, deadline - Date.now()));
    if (probe.kind === "ready") {
      return { listen: probe.listen, host: probe.host };
    }
    const nextState = announceProgress(args.home, state, args.onStatus);
    if (Date.now() >= deadline) {
      throw createTimeoutError();
    }
    await sleep(200);
    return poll(nextState);
  }

  return poll({ lastStatus: "", lastPrintedAt: 0 });
}

function printNextSteps(pairingUrl: string | null, paseoHome: string, richUi: boolean): void {
  const daemonLogPath = path.join(paseoHome, "daemon.log");
  const nextStepsLines = [
    pairingUrl
      ? "1. Open Paseo and scan the QR code above, or paste the pairing link."
      : "1. Open Paseo and connect to your daemon.",
    "2. Web app: https://app.paseo.sh",
    "3. Desktop app: https://github.com/getpaseo/paseo/releases/latest",
    "4. Docs: https://paseo.sh/docs",
    '5. Example: paseo run --output-schema schema.json "extract fields"',
  ];
  const quickReferenceLines = [
    "1. paseo --help",
    "2. paseo ls",
    '3. paseo run "your prompt"',
    "4. paseo status",
    `5. Daemon logs: ${daemonLogPath}`,
  ];

  if (!richUi) {
    console.log("");
    console.log("Next steps:");
    for (const line of nextStepsLines) {
      console.log(line);
    }
    console.log("");
    console.log("CLI quick reference:");
    for (const line of quickReferenceLines) {
      console.log(line);
    }
    return;
  }

  renderNote(nextStepsLines.join("\n"), "Next steps");
  renderNote(quickReferenceLines.join("\n"), "CLI quick reference");
}

export function onboardCommand(): Command {
  return new Command("onboard")
    .description("Run first-time setup, start daemon, and print pairing instructions")
    .option("--listen <listen>", "Listen target (host:port, port, or unix socket path)")
    .option("--port <port>", "Port to listen on (default: 6767)")
    .option("--home <path>", "Paseo home directory (default: ~/.paseo)")
    .option("--relay", "Enable relay connection without prompting")
    .option("--no-relay", "Disable relay connection")
    .option("--no-mcp", "Disable the Agent MCP HTTP endpoint")
    .option(
      "--hostnames <hosts>",
      'Daemon hostnames (comma-separated, e.g. "myhost,.example.com" or "true" for any)',
    )
    .addOption(new Option("--allowed-hosts <hosts>").hideHelp())
    .option("--timeout <seconds>", "Max time to wait for daemon readiness (default: 600)")
    .option("--voice <mode>", "Voice setup mode: ask, enable, disable", "ask")
    .action(async (options: RawOnboardOptions) => {
      await runOnboard({
        ...options,
        hostnames: options.hostnames ?? options.allowedHosts,
      });
    });
}

async function resolveAndPersistVoice(
  paseoHome: string,
  options: OnboardOptions,
): Promise<boolean> {
  let persisted = loadPersistedConfig(paseoHome) as OnboardPersistedConfig;
  const persistedVoiceSelection = resolvePersistedVoiceSelection(persisted);
  const shouldPrompt = options.voice === "ask" || options.voice === undefined;
  let voiceEnabled: boolean;
  try {
    voiceEnabled =
      shouldPrompt && persistedVoiceSelection !== null
        ? persistedVoiceSelection
        : await resolveVoiceSelection(options.voice);
  } catch (error) {
    if (error instanceof OnboardCancelledError) {
      cancel("Onboarding cancelled.");
      process.exit(0);
    }
    throw error;
  }

  if (shouldPrompt && persistedVoiceSelection !== null) {
    log.message(`Using saved voice setup from config (${voiceEnabled ? "enabled" : "disabled"}).`);
  }

  persisted = applyVoiceSelection(persisted, voiceEnabled);
  savePersistedConfig(paseoHome, persisted);
  return voiceEnabled;
}

async function ensureDaemonStarted(options: OnboardOptions, richUi: boolean): Promise<void> {
  const stateBeforeStart = resolveLocalDaemonState({ home: options.home });
  if (stateBeforeStart.running) {
    log.message(`Daemon already running (PID ${stateBeforeStart.pidInfo?.pid ?? "unknown"}).`);
    return;
  }

  const startSpinner = richUi ? spinner() : null;
  try {
    if (startSpinner) {
      startSpinner.start("Starting daemon...");
    } else {
      log.message("Starting daemon...");
    }
    const startup = await startLocalDaemonDetached(options);
    if (startSpinner) {
      startSpinner.stop(`Daemon started (PID ${startup.pid ?? "unknown"})`);
    } else {
      log.message(`Daemon started (PID ${startup.pid ?? "unknown"})`);
    }
    log.message(`Logs: ${startup.logPath}`);
  } catch (error) {
    const message = error instanceof Error ? error.message : String(error);
    if (startSpinner) {
      startSpinner.error(message);
    } else {
      log.error(message);
    }
    process.exit(1);
  }
}

async function waitForDaemonReadyWithUi(args: {
  home: string;
  timeoutMs: number;
  richUi: boolean;
}): Promise<{ listen: string; host: string | null }> {
  const readySpinner = args.richUi ? spinner() : null;
  try {
    if (readySpinner) {
      readySpinner.start("Waiting for daemon to become ready...");
    } else {
      log.message("Waiting for daemon to become ready...");
    }
    const readyState = await waitForDaemonReady({
      home: args.home,
      timeoutMs: args.timeoutMs,
      onStatus: readySpinner ? (message) => readySpinner.message(message) : undefined,
    });
    if (readySpinner) {
      readySpinner.stop(`Daemon ready on ${readyState.listen}`);
    } else {
      log.message(`Daemon ready on ${readyState.listen}`);
    }
    return readyState;
  } catch (error) {
    const message = error instanceof Error ? error.message : String(error);
    if (readySpinner) {
      readySpinner.error(message);
    } else {
      log.error(message);
    }
    return process.exit(1);
  }
}

export async function runOnboard(options: OnboardOptions): Promise<void> {
  const richUi = process.stdin.isTTY && process.stdout.isTTY;
  if (richUi) {
    intro("Welcome to Paseo");
  }

  if (options.listen && options.port) {
    cancel("Cannot use --listen and --port together");
    process.exit(1);
  }

  let timeoutMs = DEFAULT_READY_TIMEOUT_MS;
  try {
    timeoutMs = parseTimeoutMs(options.timeout);
  } catch (error) {
    const message = error instanceof Error ? error.message : String(error);
    cancel(message);
    process.exit(1);
  }

  const paseoHome = resolveLocalPaseoHome(options.home);
  if (richUi) {
    renderNote(paseoHome, "Paseo home");
  }

  const voiceEnabled = await resolveAndPersistVoice(paseoHome, options);
  log.message(
    voiceEnabled
      ? "Voice features enabled. Local speech models will be downloaded automatically if missing."
      : "Voice features disabled. Local speech models will not be downloaded.",
  );

  await ensureDaemonStarted(options, richUi);
  await waitForDaemonReadyWithUi({
    home: options.home ?? paseoHome,
    timeoutMs,
    richUi,
  });

  if (options.relay === false) {
    log.message("Relay pairing skipped because --no-relay was provided.");
    printNextSteps(null, paseoHome, richUi);
    if (richUi) outro("Paseo daemon is running.");
    return;
  }

  let pairing = await resolveLocalPairingOffer({
    paseoHome,
    enableRelay: options.relay === true,
  });

  if (!pairing.relayEnabled) {
    const shouldEnable = richUi ? await confirmRelayPairing() : false;
    if (!shouldEnable) {
      printDirectConnectionGuidance();
      printNextSteps(null, paseoHome, richUi);
      if (richUi) outro("Paseo daemon is running.");
      return;
    }
    pairing = await resolveLocalPairingOffer({ paseoHome, enableRelay: true });
    log.success("Relay enabled");
  }

  if (!pairing.url) {
    log.warn("Relay pairing URL is unavailable for this daemon configuration.");
    printNextSteps(null, paseoHome, richUi);
    if (richUi) {
      outro("Paseo daemon is running.");
    }
    return;
  }

  process.stdout.write(
    formatPairingInstructions({
      url: pairing.url,
      qr: pairing.qr,
      columns: process.stdout.columns,
    }),
  );
  printNextSteps(pairing.url, paseoHome, richUi);
  if (richUi) {
    outro("Paseo is ready!");
  }
}