import type { OpenClawPluginApi } from "openclaw/plugin-sdk";
import type { ChannelStore } from "../core/channel-store.js";
import type { IdentityRegistry } from "../core/identity-registry.js";
import { parseDiscordChannelId } from "./before-model-resolve.js";
import {
  isCurrentSpeaker,
  getAnchor,
  advanceSpeaker,
  wakeFromDormant,
  hasSpeakers,
  getDebugInfo,
  isTurnPending,
  clearTurnPending,
  consumeBlockedPending,
  type SpeakerEntry,
} from "../turn-manager.js";
import { fetchVisibleChannelBotAccountIds } from "../core/channel-members.js";
import { pollForTailMatch, sendAndDelete } from "../core/moderator-discord.js";

const TAIL_LENGTH = 40;
const TAIL_MATCH_TIMEOUT_MS = 15_000;

/**
 * Process-level deduplication for agent_end events.
 * OpenClaw hot-reloads plugin modules (re-imports), stacking duplicate handlers.
 * Using globalThis ensures the dedup Set survives module reloads and is shared
 * by all handler instances in the same process.
 */
const _AGENT_END_DEDUP_KEY = "_dirigentProcessedAgentEndRunIds";
if (!(globalThis as Record<string, unknown>)[_AGENT_END_DEDUP_KEY]) {
  (globalThis as Record<string, unknown>)[_AGENT_END_DEDUP_KEY] = new Set<string>();
}
const processedAgentEndRunIds: Set<string> = (globalThis as Record<string, unknown>)[_AGENT_END_DEDUP_KEY] as Set<string>;

/** Extract plain text from agent_end event.messages last assistant entry. */
function extractFinalText(messages: unknown[]): string {
  for (let i = messages.length - 1; i >= 0; i--) {
    const msg = messages[i] as Record<string, unknown> | null;
    if (!msg || msg.role !== "assistant") continue;
    const content = msg.content;
    if (typeof content === "string") return content;
    if (Array.isArray(content)) {
      let text = "";
      for (const part of content) {
        const p = part as Record<string, unknown>;
        if (p?.type === "text" && typeof p.text === "string") text += p.text;
      }
      return text;
    }
    break;
  }
  return "";
}

function isEmptyTurn(text: string): boolean {
  const t = text.trim();
  return t === "" || /^NO$/i.test(t) || /^NO_REPLY$/i.test(t);
}

export type AgentEndDeps = {
  api: OpenClawPluginApi;
  channelStore: ChannelStore;
  identityRegistry: IdentityRegistry;
  moderatorBotToken: string | undefined;
  scheduleIdentifier: string;
  /** Called when discussion channel enters dormant — to send idle reminder. */
  onDiscussionDormant?: (channelId: string) => Promise<void>;
};

/** Exposed so message-received can interrupt an in-progress tail-match wait. */
export type InterruptFn = (channelId: string) => void;

export function registerAgentEndHook(deps: AgentEndDeps): InterruptFn {
  const { api, channelStore, identityRegistry, moderatorBotToken, scheduleIdentifier, onDiscussionDormant } = deps;

  const interruptedChannels = new Set<string>();

  function interrupt(channelId: string): void {
    interruptedChannels.add(channelId);
    setTimeout(() => interruptedChannels.delete(channelId), 5000);
  }

  async function buildSpeakerList(channelId: string): Promise<SpeakerEntry[]> {
    if (!moderatorBotToken) return [];
    const agentIds = await fetchVisibleChannelBotAccountIds(api, channelId, identityRegistry);
    const result: SpeakerEntry[] = [];
    for (const agentId of agentIds) {
      const identity = identityRegistry.findByAgentId(agentId);
      if (identity) result.push({ agentId, discordUserId: identity.discordUserId });
    }
    return result;
  }

  async function triggerNextSpeaker(channelId: string, next: SpeakerEntry): Promise<void> {
    if (!moderatorBotToken) return;
    const msg = `<@${next.discordUserId}>${scheduleIdentifier}`;
    await sendAndDelete(moderatorBotToken, channelId, msg, api.logger);
    api.logger.info(`dirigent: triggered next speaker agentId=${next.agentId} channel=${channelId}`);
  }

  api.on("agent_end", async (event, ctx) => {
    try {
      // Deduplicate: skip if this runId was already processed by another handler
      // instance (can happen when OpenClaw hot-reloads the plugin in the same process).
      const runId = (event as Record<string, unknown>).runId as string | undefined;
      if (runId) {
        if (processedAgentEndRunIds.has(runId)) return;
        processedAgentEndRunIds.add(runId);
        // Evict old entries to prevent unbounded growth (keep last 500)
        if (processedAgentEndRunIds.size > 500) {
          const oldest = processedAgentEndRunIds.values().next().value;
          if (oldest) processedAgentEndRunIds.delete(oldest);
        }
      }

      const sessionKey = ctx.sessionKey;
      if (!sessionKey) return;

      const channelId = parseDiscordChannelId(sessionKey);
      if (!channelId) return;

      const mode = channelStore.getMode(channelId);
      if (mode === "none" || mode === "work" || mode === "report") return;

      if (!hasSpeakers(channelId)) return;

      const agentId = ctx.agentId;
      if (!agentId) return;
      if (!isCurrentSpeaker(channelId, agentId)) return;

      // Only process agent_ends for turns that were explicitly started by before_model_resolve.
      // This prevents stale NO_REPLY completions (from initial suppression) from being counted.
      if (!isTurnPending(channelId, agentId)) {
        api.logger.info(`dirigent: agent_end skipping stale turn agentId=${agentId} channel=${channelId}`);
        return;
      }

      // Consume a blocked-pending slot if any exists. These are NO_REPLY completions
      // from before_model_resolve blocking events (non-speaker or init-suppressed) that
      // fire late — after the agent became the current speaker — due to history-building
      // overhead (~10s). We skip them until the counter is exhausted, at which point
      // the next agent_end is the real LLM response.
      if (consumeBlockedPending(channelId, agentId)) {
        api.logger.info(`dirigent: agent_end skipping blocked-pending NO_REPLY agentId=${agentId} channel=${channelId}`);
        return;
      }

      clearTurnPending(channelId, agentId);

      const messages = Array.isArray((event as Record<string, unknown>).messages)
        ? ((event as Record<string, unknown>).messages as unknown[])
        : [];
      const finalText = extractFinalText(messages);
      const empty = isEmptyTurn(finalText);

      api.logger.info(
        `dirigent: agent_end channel=${channelId} agentId=${agentId} empty=${empty} text=${finalText.slice(0, 80)}`,
      );

      if (!empty) {
        // Real turn: wait for Discord delivery via tail-match polling
        const identity = identityRegistry.findByAgentId(agentId);
        if (identity && moderatorBotToken) {
          const anchorId = getAnchor(channelId, agentId) ?? "0";
          const tail = [...finalText].slice(-TAIL_LENGTH).join("");

          const { matched, interrupted } = await pollForTailMatch({
            token: moderatorBotToken,
            channelId,
            anchorId,
            agentDiscordUserId: identity.discordUserId,
            tailFingerprint: tail,
            timeoutMs: TAIL_MATCH_TIMEOUT_MS,
            isInterrupted: () => interruptedChannels.has(channelId),
          });

          if (interrupted) {
            api.logger.info(`dirigent: tail-match interrupted channel=${channelId} — wake-from-dormant`);
            const first = wakeFromDormant(channelId);
            if (first) await triggerNextSpeaker(channelId, first);
            return;
          }
          if (!matched) {
            api.logger.warn(`dirigent: tail-match timeout channel=${channelId} agentId=${agentId} — advancing anyway`);
          }
        }
      }

      // Determine shuffle mode from current list size
      const debugBefore = getDebugInfo(channelId);
      const currentListSize = debugBefore.exists ? (debugBefore.speakerList?.length ?? 0) : 0;
      const isShuffle = currentListSize > 2;
      // In shuffle mode, pass agentId as previousLastAgentId so new list avoids it as first
      const previousLastAgentId = isShuffle ? agentId : undefined;

      const { next, enteredDormant } = await advanceSpeaker(
        channelId,
        agentId,
        empty,
        () => buildSpeakerList(channelId),
        previousLastAgentId,
      );

      if (enteredDormant) {
        api.logger.info(`dirigent: channel=${channelId} entered dormant`);
        if (mode === "discussion") {
          await onDiscussionDormant?.(channelId).catch((err) => {
            api.logger.warn(`dirigent: onDiscussionDormant failed: ${String(err)}`);
          });
        }
        return;
      }

      if (next) await triggerNextSpeaker(channelId, next);
    } catch (err) {
      api.logger.warn(`dirigent: agent_end hook error: ${String(err)}`);
    }
  });

  return interrupt;
}