import { completeSimple, type Api, type AssistantMessage, type Model } from "@mariozechner/pi-ai";
import { loadConfig } from "../config/config.js";
import { isTruthyEnvValue } from "../infra/env.js";
import { resolveOpenClawAgentDir } from "./agent-paths.js";
import { collectProviderApiKeys } from "./live-auth-keys.js";
import { isLiveTestEnabled } from "./live-test-helpers.js";
import { getApiKeyForModel, requireApiKey } from "./model-auth.js";
import { normalizeProviderId, parseModelRef } from "./model-selection.js";
import { ensureOpenClawModelsJson } from "./models-config.js";
import { discoverAuthStorage, discoverModels } from "./pi-model-discovery.js";
import { buildAssistantMessageWithZeroUsage } from "./stream-message-shared.js";

export const LIVE_CACHE_TEST_ENABLED =
  isLiveTestEnabled() && isTruthyEnvValue(process.env.OPENCLAW_LIVE_CACHE_TEST);

const DEFAULT_HEARTBEAT_MS = 20_000;
const DEFAULT_TIMEOUT_MS = 90_000;

type LiveResolvedModel = {
  apiKey: string;
  model: Model<Api>;
};

function toInt(value: string | undefined, fallback: number): number {
  const trimmed = value?.trim();
  if (!trimmed) {
    return fallback;
  }
  const parsed = Number.parseInt(trimmed, 10);
  return Number.isFinite(parsed) ? parsed : fallback;
}

export function logLiveCache(message: string): void {
  process.stderr.write(`[live-cache] ${message}\n`);
}

export async function withLiveCacheHeartbeat<T>(
  operation: Promise<T>,
  context: string,
): Promise<T> {
  const heartbeatMs = Math.max(
    1_000,
    toInt(process.env.OPENCLAW_LIVE_HEARTBEAT_MS, DEFAULT_HEARTBEAT_MS),
  );
  const startedAt = Date.now();
  let heartbeatCount = 0;
  const timer = setInterval(() => {
    heartbeatCount += 1;
    logLiveCache(
      `${context}: still running (${Math.max(1, Math.round((Date.now() - startedAt) / 1_000))}s)`,
    );
  }, heartbeatMs);
  timer.unref?.();
  try {
    return await operation;
  } finally {
    clearInterval(timer);
    if (heartbeatCount > 0) {
      logLiveCache(
        `${context}: completed (${Math.max(1, Math.round((Date.now() - startedAt) / 1_000))}s)`,
      );
    }
  }
}

export async function completeSimpleWithLiveTimeout<TApi extends Api>(
  model: Model<TApi>,
  context: Parameters<typeof completeSimple<TApi>>[1],
  options: Parameters<typeof completeSimple<TApi>>[2],
  progressContext: string,
  timeoutMs = Math.max(
    1_000,
    toInt(process.env.OPENCLAW_LIVE_MODEL_TIMEOUT_MS, DEFAULT_TIMEOUT_MS),
  ),
): Promise<AssistantMessage> {
  const controller = new AbortController();
  const abortTimer = setTimeout(() => controller.abort(), timeoutMs);
  abortTimer.unref?.();
  let hardTimer: ReturnType<typeof setTimeout> | undefined;
  const timeout = new Promise<never>((_, reject) => {
    hardTimer = setTimeout(() => {
      reject(new Error(`${progressContext} timed out after ${timeoutMs}ms`));
    }, timeoutMs);
    hardTimer.unref?.();
  });
  try {
    return await withLiveCacheHeartbeat(
      Promise.race([
        completeSimple(model, context, {
          ...options,
          signal: controller.signal,
        }),
        timeout,
      ]),
      progressContext,
    );
  } finally {
    clearTimeout(abortTimer);
    if (hardTimer) {
      clearTimeout(hardTimer);
    }
  }
}

export function buildStableCachePrefix(tag: string, sections = 160): string {
  const lines = [
    `Stable cache prefix for ${tag}.`,
    "Preserve this prefix byte-for-byte across retries.",
    "Return only the requested marker from the final user message.",
  ];
  for (let index = 0; index < sections; index += 1) {
    lines.push(
      `Section ${index + 1}: deterministic cache prose with repeated lexical material about routing, invariants, transcript stability, prefix locality, provider usage accounting, and session affinity.`,
    );
  }
  return lines.join("\n");
}

export function extractAssistantText(message: AssistantMessage): string {
  return message.content
    .filter((block) => block.type === "text")
    .map((block) => block.text.trim())
    .filter(Boolean)
    .join(" ");
}

export function buildAssistantHistoryTurn(
  text: string,
  model?: Pick<Model<Api>, "api" | "provider" | "id">,
): AssistantMessage {
  return buildAssistantMessageWithZeroUsage({
    model: {
      api: model?.api ?? "openai-responses",
      provider: model?.provider ?? "openai",
      id: model?.id ?? "test-model",
    },
    content: [{ type: "text", text }],
    stopReason: "stop",
    timestamp: Date.now(),
  });
}

export function computeCacheHitRate(usage: {
  input?: number;
  cacheRead?: number;
  cacheWrite?: number;
}): number {
  const input = usage.input ?? 0;
  const cacheRead = usage.cacheRead ?? 0;
  const cacheWrite = usage.cacheWrite ?? 0;
  const totalPrompt = input + cacheRead + cacheWrite;
  if (totalPrompt <= 0 || cacheRead <= 0) {
    return 0;
  }
  return cacheRead / totalPrompt;
}

export async function resolveLiveDirectModel(params: {
  provider: "anthropic" | "openai";
  api: "anthropic-messages" | "openai-responses";
  envVar: string;
  preferredModelIds: readonly string[];
}): Promise<LiveResolvedModel> {
  const cfg = loadConfig();
  await ensureOpenClawModelsJson(cfg);
  const agentDir = resolveOpenClawAgentDir();
  const authStorage = discoverAuthStorage(agentDir);
  const models = discoverModels(authStorage, agentDir).getAll();

  const rawModel = process.env[params.envVar]?.trim();
  const parsed = rawModel ? parseModelRef(rawModel, params.provider) : null;
  const candidates = models.filter(
    (model) => normalizeProviderId(model.provider) === params.provider && model.api === params.api,
  );

  let resolvedModel: Model<Api> | undefined;
  if (parsed) {
    resolvedModel = candidates.find(
      (model) =>
        normalizeProviderId(model.provider) === parsed.provider && model.id === parsed.model,
    );
  }
  if (!resolvedModel) {
    resolvedModel = params.preferredModelIds
      .map((id) => candidates.find((model) => model.id === id))
      .find(Boolean);
  }
  if (!resolvedModel) {
    throw new Error(
      rawModel
        ? `Model not found for ${params.provider}: ${rawModel}`
        : `No ${params.provider} ${params.api} model available in registry.`,
    );
  }

  const liveKeys = collectProviderApiKeys(params.provider);
  const apiKey =
    liveKeys[0] ??
    requireApiKey(
      await getApiKeyForModel({
        model: resolvedModel,
        cfg,
        agentDir,
      }),
      resolvedModel.provider,
    );
  return {
    model: resolvedModel,
    apiKey,
  };
}