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,
  isDormant,
  hasSpeakers,
  getDebugInfo,
  isTurnPending,
  clearTurnPending,
  consumeBlockedPending,
  type SpeakerEntry,
} from "../turn-manager.js";
import { fetchVisibleChannelBotAccountIds } from "../core/channel-members.js";
import { pollForTailMatch, sendScheduleTrigger } from "../core/moderator-discord.js";

/**
 * 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>;

/**
 * Per-channel advance lock: prevents two concurrent agent_end handler instances
 * (from different VM contexts with different runIds) from both calling advanceSpeaker
 * for the same channel at the same time, which would double-advance the speaker index.
 */
const _ADVANCE_LOCK_KEY = "_dirigentAdvancingChannels";
if (!(globalThis as Record<string, unknown>)[_ADVANCE_LOCK_KEY]) {
  (globalThis as Record<string, unknown>)[_ADVANCE_LOCK_KEY] = new Set<string>();
}
const advancingChannels: Set<string> = (globalThis as Record<string, unknown>)[_ADVANCE_LOCK_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();
  if (t === "") return true;
  // Check if the last non-empty line is NO or NO_REPLY (agents often write
  // explanatory text before the final answer on the last line).
  const lines = t.split("\n").map((l) => l.trim()).filter((l) => l !== "");
  const last = lines[lines.length - 1] ?? "";
  return /^NO$/i.test(last) || /^NO_REPLY$/i.test(last);
}

export type AgentEndDeps = {
  api: OpenClawPluginApi;
  channelStore: ChannelStore;
  identityRegistry: IdentityRegistry;
  moderatorBotToken: string | undefined;
  scheduleIdentifier: string;
  debugMode: boolean;
  /** 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, debugMode, 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 sendScheduleTrigger(moderatorBotToken, channelId, msg, api.logger, debugMode);
    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;

      // Extract final text early so we can drain blocked_pending at every early-return point.
      // This prevents the counter from staying inflated when stale NO_REPLYs are discarded
      // by !isCurrentSpeaker or !isTurnPending without reaching consumeBlockedPending.
      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);

      if (!isCurrentSpeaker(channelId, agentId)) {
        // Drain blocked_pending for non-speaker stale NO_REPLYs. Without this, suppressions
        // that happen while this agent is not the current speaker inflate the counter and cause
        // its subsequent real empty turn to be misidentified as stale.
        if (empty) consumeBlockedPending(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}`);
        // Also drain here: stale may arrive after clearTurnPending but before markTurnStarted.
        if (empty) consumeBlockedPending(channelId, agentId);
        return;
      }

      // Consume a blocked-pending slot only for self-wakeup stales: NO_REPLY completions
      // from suppressed self-wakeup before_model_resolve calls that fire while the agent
      // is current speaker with a turn already in progress.
      if (empty && consumeBlockedPending(channelId, agentId)) {
        api.logger.info(`dirigent: agent_end skipping blocked-pending NO_REPLY agentId=${agentId} channel=${channelId}`);
        return;
      }

      clearTurnPending(channelId, agentId);

      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 before triggering next speaker.
        // Anchor was set in before_model_resolve just before the LLM call, so any
        // message from the agent after the anchor must be from this turn.
        const identity = identityRegistry.findByAgentId(agentId);
        if (identity && moderatorBotToken) {
          const anchorId = getAnchor(channelId, agentId) ?? "0";

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

          if (interrupted) {
            if (isDormant(channelId)) {
              // Channel is dormant: a new external message woke it — restart from first speaker
              api.logger.info(`dirigent: tail-match interrupted (dormant) channel=${channelId} — waking`);
              const first = wakeFromDormant(channelId);
              if (first) await triggerNextSpeaker(channelId, first);
              return;
            }
            // Not dormant: interrupt was a spurious trigger (e.g. moderator bot message).
            // Fall through to normal advance so the turn cycle continues correctly.
            api.logger.info(`dirigent: tail-match interrupted (non-dormant) channel=${channelId} — advancing normally`);
          }
        }
      }

      // Guard against concurrent advanceSpeaker calls for the same channel.
      // Two VM context instances may both reach this point with different runIds
      // (when the dedup Set doesn't catch them); only the first should advance.
      if (advancingChannels.has(channelId)) {
        api.logger.info(`dirigent: agent_end advance already in progress, skipping channel=${channelId} agentId=${agentId}`);
        return;
      }
      advancingChannels.add(channelId);

      let next: ReturnType<typeof import("../turn-manager.js").getCurrentSpeaker> | null = null;
      let enteredDormant = false;
      try {
        // 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;

        ({ next, enteredDormant } = await advanceSpeaker(
          channelId,
          agentId,
          empty,
          () => buildSpeakerList(channelId),
          previousLastAgentId,
        ));
      } finally {
        advancingChannels.delete(channelId);
      }

      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;
}