import fs from "node:fs/promises";
import { hasConfiguredModelFallbacks, resolveSessionAgentId } from "../../agents/agent-scope.js";
import { resolveContextTokensForModel } from "../../agents/context.js";
import { DEFAULT_CONTEXT_TOKENS } from "../../agents/defaults.js";
import { resolveModelAuthMode } from "../../agents/model-auth.js";
import { isCliProvider } from "../../agents/model-selection.js";
import { queueEmbeddedPiMessage } from "../../agents/pi-embedded-runner/runs.js";
import { hasNonzeroUsage, normalizeUsage } from "../../agents/usage.js";
import {
  loadSessionStore,
  resolveSessionPluginStatusLines,
  resolveSessionPluginTraceLines,
  type SessionEntry,
  updateSessionStoreEntry,
} from "../../config/sessions.js";
import type { TypingMode } from "../../config/types.js";
import { resolveSessionTranscriptCandidates } from "../../gateway/session-utils.fs.js";
import { emitAgentEvent } from "../../infra/agent-events.js";
import { emitDiagnosticEvent, isDiagnosticsEnabled } from "../../infra/diagnostic-events.js";
import { enqueueSystemEvent } from "../../infra/system-events.js";
import { CommandLaneClearedError, GatewayDrainingError } from "../../process/command-queue.js";
import { normalizeOptionalString } from "../../shared/string-coerce.js";
import {
  estimateUsageCost,
  formatTokenCount,
  resolveModelCostConfig,
} from "../../utils/usage-format.js";
import {
  buildFallbackClearedNotice,
  buildFallbackNotice,
  resolveFallbackTransition,
} from "../fallback-state.js";
import type { OriginatingChannelType, TemplateContext } from "../templating.js";
import { resolveResponseUsageMode, type VerboseLevel } from "../thinking.js";
import { SILENT_REPLY_TOKEN } from "../tokens.js";
import type { GetReplyOptions, ReplyPayload } from "../types.js";
import { runAgentTurnWithFallback } from "./agent-runner-execution.js";
import {
  createShouldEmitToolOutput,
  createShouldEmitToolResult,
  finalizeWithFollowup,
  isAudioPayload,
  signalTypingIfNeeded,
} from "./agent-runner-helpers.js";
import { runMemoryFlushIfNeeded, runPreflightCompactionIfNeeded } from "./agent-runner-memory.js";
import { buildReplyPayloads } from "./agent-runner-payloads.js";
import {
  appendUnscheduledReminderNote,
  hasSessionRelatedCronJobs,
  hasUnbackedReminderCommitment,
} from "./agent-runner-reminder-guard.js";
import { resetReplyRunSession } from "./agent-runner-session-reset.js";
import { appendUsageLine, formatResponseUsageLine } from "./agent-runner-usage-line.js";
import { resolveQueuedReplyExecutionConfig } from "./agent-runner-utils.js";
import { createAudioAsVoiceBuffer, createBlockReplyPipeline } from "./block-reply-pipeline.js";
import { resolveEffectiveBlockStreamingConfig } from "./block-streaming.js";
import { createFollowupRunner } from "./followup-runner.js";
import { resolveOriginMessageProvider, resolveOriginMessageTo } from "./origin-routing.js";
import { readPostCompactionContext } from "./post-compaction-context.js";
import { resolveActiveRunQueueAction } from "./queue-policy.js";
import {
  enqueueFollowupRun,
  refreshQueuedFollowupSession,
  type FollowupRun,
  type QueueSettings,
} from "./queue.js";
import { createReplyMediaPathNormalizer } from "./reply-media-paths.js";
import {
  createReplyOperation,
  ReplyRunAlreadyActiveError,
  replyRunRegistry,
  type ReplyOperation,
} from "./reply-run-registry.js";
import { createReplyToModeFilterForChannel, resolveReplyToMode } from "./reply-threading.js";
import { incrementRunCompactionCount, persistRunSessionUsage } from "./session-run-accounting.js";
import { createTypingSignaler } from "./typing-mode.js";
import type { TypingController } from "./typing.js";

const BLOCK_REPLY_SEND_TIMEOUT_MS = 15_000;

function buildInlinePluginStatusPayload(params: {
  entry: SessionEntry | undefined;
  includeTraceLines: boolean;
}): ReplyPayload | undefined {
  const statusLines =
    params.entry?.verboseLevel && params.entry.verboseLevel !== "off"
      ? resolveSessionPluginStatusLines(params.entry)
      : [];
  const traceLines =
    params.includeTraceLines &&
    (params.entry?.traceLevel === "on" || params.entry?.traceLevel === "raw")
      ? resolveSessionPluginTraceLines(params.entry)
      : [];
  const lines = [...statusLines, ...traceLines];
  if (lines.length === 0) {
    return undefined;
  }
  return { text: lines.join("\n") };
}

function formatRawTraceBlock(title: string, value: string | undefined): string {
  const body = value?.trim() ? escapeTraceFence(value) : "<empty>";
  return `🔎 ${title}:\n~~~text\n${body}\n~~~`;
}

function escapeTraceFence(value: string): string {
  return value.replace(/^~~~/gm, "\\~~~");
}

function hasTraceUsageFields(
  usage:
    | {
        input?: number;
        output?: number;
        cacheRead?: number;
        cacheWrite?: number;
        total?: number;
      }
    | undefined,
): boolean {
  if (!usage) {
    return false;
  }
  return ["input", "output", "cacheRead", "cacheWrite", "total"].some((key) => {
    const value = usage[key as keyof typeof usage];
    return typeof value === "number" && Number.isFinite(value);
  });
}

function formatTraceUsageLine(label: string, value: number | undefined): string {
  return `${label}=${typeof value === "number" && Number.isFinite(value) ? `${value.toLocaleString()} tok (${formatTokenCount(value)})` : "n/a"}`;
}

function formatUsageTraceBlock(
  title: string,
  usage:
    | {
        input?: number;
        output?: number;
        cacheRead?: number;
        cacheWrite?: number;
        total?: number;
      }
    | undefined,
): string | undefined {
  if (!hasTraceUsageFields(usage)) {
    return undefined;
  }
  return `🔎 ${title}:\n~~~text\n${[
    formatTraceUsageLine("input", usage?.input),
    formatTraceUsageLine("output", usage?.output),
    formatTraceUsageLine("cacheRead", usage?.cacheRead),
    formatTraceUsageLine("cacheWrite", usage?.cacheWrite),
    formatTraceUsageLine("total", usage?.total),
  ].join("\n")}\n~~~`;
}

type TraceAttemptView = {
  provider: string;
  model: string;
  result: string;
  reason?: string;
  stage?: string;
  elapsedMs?: number;
  status?: number;
};

type TraceExecutionView = {
  winnerProvider?: string;
  winnerModel?: string;
  attempts?: TraceAttemptView[];
  fallbackUsed?: boolean;
  runner?: "embedded" | "cli";
};

type TracePromptSegmentView = {
  key: string;
  chars: number;
};

type TraceToolSummaryView = {
  calls: number;
  tools: string[];
  failures?: number;
  totalToolTimeMs?: number;
};

type TraceCompletionView = {
  finishReason?: string;
  stopReason?: string;
  refusal?: boolean;
};

type TraceContextManagementView = {
  sessionCompactions?: number;
  lastTurnCompactions?: number;
  preflightCompactionApplied?: boolean;
  postCompactionContextInjected?: boolean;
};

function formatTraceScalar(value: string | number | boolean | undefined): string | undefined {
  if (typeof value === "boolean") {
    return value ? "yes" : "no";
  }
  if (typeof value === "number") {
    return Number.isFinite(value) ? value.toLocaleString() : undefined;
  }
  const trimmed = normalizeOptionalString(value);
  return trimmed ?? undefined;
}

function formatKeyValueTraceBlock(
  title: string,
  fields: Array<[string, string | number | boolean | undefined]>,
): string | undefined {
  const lines = fields.flatMap(([key, rawValue]) => {
    const value = formatTraceScalar(rawValue);
    return value ? [`${key}=${value}`] : [];
  });
  if (lines.length === 0) {
    return undefined;
  }
  return `🔎 ${title}:\n~~~text\n${lines.join("\n")}\n~~~`;
}

function inferFallbackAttemptResult(attempt: { reason?: string; status?: number }): string {
  if (attempt.reason === "timeout") {
    return "timeout";
  }
  return "candidate_failed";
}

function mergeExecutionTrace(params: {
  fallbackAttempts?: Array<{
    provider: string;
    model: string;
    reason?: string;
    status?: number;
  }>;
  executionTrace?: {
    winnerProvider?: string;
    winnerModel?: string;
    attempts?: TraceAttemptView[];
    fallbackUsed?: boolean;
    runner?: "embedded" | "cli";
  };
  provider?: string;
  model?: string;
  runner: "embedded" | "cli";
}): TraceExecutionView | undefined {
  const attempts: TraceAttemptView[] = [
    ...(params.fallbackAttempts ?? []).map((attempt) => ({
      provider: attempt.provider,
      model: attempt.model,
      result: inferFallbackAttemptResult(attempt),
      ...(attempt.reason ? { reason: attempt.reason } : {}),
      ...(typeof attempt.status === "number" ? { status: attempt.status } : {}),
    })),
    ...(params.executionTrace?.attempts ?? []),
  ];
  const winnerProvider =
    params.executionTrace?.winnerProvider ?? normalizeOptionalString(params.provider);
  const winnerModel = params.executionTrace?.winnerModel ?? normalizeOptionalString(params.model);
  if (
    winnerProvider &&
    winnerModel &&
    !attempts.some(
      (attempt) =>
        attempt.provider === winnerProvider &&
        attempt.model === winnerModel &&
        attempt.result === "success",
    )
  ) {
    attempts.push({
      provider: winnerProvider,
      model: winnerModel,
      result: "success",
    });
  }
  if (!winnerProvider && !winnerModel && attempts.length === 0) {
    return undefined;
  }
  return {
    winnerProvider,
    winnerModel,
    attempts: attempts.length > 0 ? attempts : undefined,
    fallbackUsed: params.executionTrace?.fallbackUsed ?? attempts.length > 1,
    runner: params.executionTrace?.runner ?? params.runner,
  };
}

function formatExecutionResultTraceBlock(
  executionTrace: TraceExecutionView | undefined,
): string | undefined {
  if (!executionTrace?.winnerProvider && !executionTrace?.winnerModel) {
    return undefined;
  }
  return formatKeyValueTraceBlock("Execution Result", [
    [
      "winner",
      executionTrace.winnerProvider && executionTrace.winnerModel
        ? `${executionTrace.winnerProvider}/${executionTrace.winnerModel}`
        : undefined,
    ],
    ["fallbackUsed", executionTrace.fallbackUsed],
    ["attempts", executionTrace.attempts?.length],
    ["runner", executionTrace.runner],
  ]);
}

function formatFallbackChainTraceBlock(
  executionTrace: TraceExecutionView | undefined,
): string | undefined {
  const attempts = executionTrace?.attempts ?? [];
  if (attempts.length <= 1) {
    return undefined;
  }
  const body = attempts
    .map((attempt, index) =>
      [
        `${index + 1}. ${attempt.provider}/${attempt.model}`,
        `   result=${attempt.result}`,
        ...(attempt.reason ? [`   reason=${attempt.reason}`] : []),
        ...(attempt.stage ? [`   stage=${attempt.stage}`] : []),
        ...(typeof attempt.elapsedMs === "number"
          ? [`   elapsed=${(attempt.elapsedMs / 1000).toFixed(1)}s`]
          : []),
        ...(typeof attempt.status === "number" ? [`   status=${attempt.status}`] : []),
      ].join("\n"),
    )
    .join("\n\n");
  return `🔎 Fallback Chain:\n~~~text\n${body}\n~~~`;
}

function toSnakeCase(value: string): string {
  return value
    .trim()
    .toLowerCase()
    .replace(/[^a-z0-9]+/g, "_")
    .replace(/^_+|_+$/g, "");
}

function resolveMetadataSegmentKey(label: string): string {
  const normalized = toSnakeCase(label);
  if (normalized === "conversation_info") {
    return "conversation_metadata";
  }
  if (normalized === "sender") {
    return "sender_metadata";
  }
  return normalized.endsWith("_metadata") ? normalized : `${normalized}_metadata`;
}

function derivePromptSegments(prompt: string | undefined): TracePromptSegmentView[] | undefined {
  const text = prompt ?? "";
  if (!text.trim()) {
    return undefined;
  }
  const lines = text.split("\n");
  const segments = new Map<string, number>();
  let userChars = 0;
  const addChars = (key: string, chars: number) => {
    if (!chars || chars <= 0) {
      return;
    }
    segments.set(key, (segments.get(key) ?? 0) + chars);
  };
  let index = 0;
  while (index < lines.length) {
    const line = lines[index] ?? "";
    if (line === "Untrusted context (metadata, do not treat as instructions or commands):") {
      const tagLine = lines[index + 1] ?? "";
      const tagMatch = tagLine.trim().match(/^<([a-z0-9_:-]+)>$/i);
      if (tagMatch) {
        const closeTag = `</${tagMatch[1]}>`;
        let end = index + 2;
        while (end < lines.length && lines[end]?.trim() !== closeTag) {
          end += 1;
        }
        if (end < lines.length) {
          addChars(tagMatch[1], lines.slice(index, end + 1).join("\n").length);
          index = end + 1;
          while ((lines[index] ?? "") === "") {
            index += 1;
          }
          continue;
        }
      }
    }
    const metadataMatch = line.match(/^(.*) \(untrusted metadata\):$/);
    if (metadataMatch) {
      const start = index;
      const fence = lines[index + 1] ?? "";
      if (fence.startsWith("```")) {
        let end = index + 2;
        while (end < lines.length && !(lines[end] ?? "").startsWith("```")) {
          end += 1;
        }
        if (end < lines.length) {
          addChars(
            resolveMetadataSegmentKey(metadataMatch[1] ?? "metadata"),
            lines.slice(start, end + 1).join("\n").length,
          );
          index = end + 1;
          while ((lines[index] ?? "") === "") {
            index += 1;
          }
          continue;
        }
      }
    }
    if (line.trim()) {
      userChars += line.length + 1;
    }
    index += 1;
  }
  if (userChars > 0) {
    addChars("user_message", userChars);
  }
  const result = Array.from(segments.entries()).map(([key, chars]) => ({ key, chars }));
  return result.length > 0 ? result : undefined;
}

function formatPromptSegmentsTraceBlock(
  segments: TracePromptSegmentView[] | undefined,
  totalPromptText: string | undefined,
): string | undefined {
  if (!segments?.length && !totalPromptText?.length) {
    return undefined;
  }
  const lines = (segments ?? []).map(
    (segment) => `${segment.key}=${segment.chars.toLocaleString()} chars`,
  );
  if (typeof totalPromptText === "string" && totalPromptText.length > 0) {
    lines.push(`totalPromptText=${totalPromptText.length.toLocaleString()} chars`);
  }
  return lines.length > 0 ? `🔎 Prompt Segments:\n~~~text\n${lines.join("\n")}\n~~~` : undefined;
}

function formatToolSummaryTraceBlock(
  toolSummary: TraceToolSummaryView | undefined,
): string | undefined {
  if (!toolSummary || toolSummary.calls <= 0) {
    return undefined;
  }
  return formatKeyValueTraceBlock("Tool Summary", [
    ["calls", toolSummary.calls],
    ["tools", toolSummary.tools.length > 0 ? toolSummary.tools.join(", ") : undefined],
    ["failures", toolSummary.failures],
    ["totalToolTimeMs", toolSummary.totalToolTimeMs],
  ]);
}

function formatCompletionTraceBlock(
  completion: TraceCompletionView | undefined,
): string | undefined {
  if (!completion) {
    return undefined;
  }
  return formatKeyValueTraceBlock("Completion", [
    ["finishReason", completion.finishReason],
    ["stopReason", completion.stopReason],
    ["refusal", completion.refusal],
  ]);
}

function formatContextManagementTraceBlock(
  contextManagement: TraceContextManagementView | undefined,
): string | undefined {
  if (!contextManagement) {
    return undefined;
  }
  return formatKeyValueTraceBlock("Context Management", [
    ["sessionCompactions", contextManagement.sessionCompactions],
    ["lastTurnCompactions", contextManagement.lastTurnCompactions],
    ["preflightCompactionApplied", contextManagement.preflightCompactionApplied],
    ["postCompactionContextInjected", contextManagement.postCompactionContextInjected],
  ]);
}

async function accumulateSessionUsageFromTranscript(params: {
  sessionId?: string;
  storePath?: string;
  sessionFile?: string;
}): Promise<
  | {
      input?: number;
      output?: number;
      cacheRead?: number;
      cacheWrite?: number;
      total?: number;
    }
  | undefined
> {
  const sessionId = normalizeOptionalString(params.sessionId);
  if (!sessionId) {
    return undefined;
  }
  try {
    const candidates = resolveSessionTranscriptCandidates(
      sessionId,
      params.storePath,
      params.sessionFile,
    );
    let transcriptText: string | undefined;
    for (const candidate of candidates) {
      try {
        transcriptText = await fs.readFile(candidate, "utf-8");
        break;
      } catch {
        continue;
      }
    }
    if (!transcriptText) {
      return undefined;
    }

    let input = 0;
    let output = 0;
    let cacheRead = 0;
    let cacheWrite = 0;
    let sawUsage = false;
    for (const line of transcriptText.split(/\r?\n/)) {
      if (!line.trim()) {
        continue;
      }
      let parsed: { message?: { usage?: unknown } } | undefined;
      try {
        parsed = JSON.parse(line) as { message?: { usage?: unknown } };
      } catch {
        continue;
      }
      const message = parsed?.message;
      if (!message) {
        continue;
      }
      const usage = normalizeUsage(message?.usage as Parameters<typeof normalizeUsage>[0]);
      if (!hasNonzeroUsage(usage)) {
        continue;
      }
      sawUsage = true;
      input += usage.input ?? 0;
      output += usage.output ?? 0;
      cacheRead += usage.cacheRead ?? 0;
      cacheWrite += usage.cacheWrite ?? 0;
    }
    if (!sawUsage) {
      return undefined;
    }
    const total = input + output + cacheRead + cacheWrite;
    return {
      input: input || undefined,
      output: output || undefined,
      cacheRead: cacheRead || undefined,
      cacheWrite: cacheWrite || undefined,
      total: total || undefined,
    };
  } catch {
    return undefined;
  }
}

function resolveRequestPromptTokens(params: {
  lastCallUsage?: {
    input?: number;
    output?: number;
    cacheRead?: number;
    cacheWrite?: number;
    total?: number;
  };
  promptTokens?: number;
  usage?: {
    input?: number;
    output?: number;
    cacheRead?: number;
    cacheWrite?: number;
    total?: number;
  };
}): number | undefined {
  const lastCall = params.lastCallUsage;
  if (lastCall) {
    const input = lastCall.input ?? 0;
    const cacheRead = lastCall.cacheRead ?? 0;
    const cacheWrite = lastCall.cacheWrite ?? 0;
    const sum = input + cacheRead + cacheWrite;
    if (sum > 0) {
      return sum;
    }
  }
  if (
    typeof params.promptTokens === "number" &&
    Number.isFinite(params.promptTokens) &&
    params.promptTokens > 0
  ) {
    return params.promptTokens;
  }
  const usage = params.usage;
  if (usage) {
    const input = usage.input ?? 0;
    const cacheRead = usage.cacheRead ?? 0;
    const cacheWrite = usage.cacheWrite ?? 0;
    const sum = input + cacheRead + cacheWrite;
    if (sum > 0) {
      return sum;
    }
  }
  return undefined;
}

function formatRequestContextTraceBlock(params: {
  provider?: string;
  model?: string;
  contextLimit?: number;
  promptTokens?: number;
}): string | undefined {
  const limit = params.contextLimit;
  const used = params.promptTokens;
  if (
    (typeof limit !== "number" || !Number.isFinite(limit) || limit <= 0) &&
    (typeof used !== "number" || !Number.isFinite(used) || used <= 0) &&
    !params.provider &&
    !params.model
  ) {
    return undefined;
  }
  const headroom =
    typeof limit === "number" &&
    Number.isFinite(limit) &&
    typeof used === "number" &&
    Number.isFinite(used)
      ? Math.max(0, limit - used)
      : undefined;
  const percent =
    typeof limit === "number" &&
    Number.isFinite(limit) &&
    limit > 0 &&
    typeof used === "number" &&
    Number.isFinite(used)
      ? Math.round((used / limit) * 100)
      : undefined;
  return `🔎 Context Window (Last Model Request):\n~~~text\n${[
    `provider=${params.provider ?? "n/a"}`,
    `model=${params.model ?? "n/a"}`,
    `used=${typeof used === "number" && Number.isFinite(used) ? `${used.toLocaleString()} tok (${formatTokenCount(used)})` : "n/a"}`,
    `limit=${typeof limit === "number" && Number.isFinite(limit) ? `${limit.toLocaleString()} tok (${formatTokenCount(limit)})` : "n/a"}`,
    `headroom=${typeof headroom === "number" ? `${headroom.toLocaleString()} tok (${formatTokenCount(headroom)})` : "n/a"}`,
    `usage=${typeof percent === "number" ? `${percent}%` : "n/a"}`,
  ].join("\n")}\n~~~`;
}

function formatSummaryPromptValue(params: {
  contextLimit?: number;
  promptTokens?: number;
}): string | undefined {
  const used = params.promptTokens;
  const limit = params.contextLimit;
  if (
    typeof used !== "number" ||
    !Number.isFinite(used) ||
    used <= 0 ||
    typeof limit !== "number" ||
    !Number.isFinite(limit) ||
    limit <= 0
  ) {
    return undefined;
  }
  return `${formatTokenCount(used)}/${formatTokenCount(limit)}`;
}

function formatRawTraceSummaryLine(params: {
  executionTrace?: TraceExecutionView;
  completion?: TraceCompletionView;
  contextLimit?: number;
  promptTokens?: number;
  usage?: {
    input?: number;
    output?: number;
    cacheRead?: number;
    cacheWrite?: number;
    total?: number;
  };
  toolSummary?: TraceToolSummaryView;
  contextManagement?: TraceContextManagementView;
  requestShaping?: {
    thinking?: string;
  };
}): string | undefined {
  const thinking = normalizeOptionalString(params.requestShaping?.thinking);
  const fields = [
    params.executionTrace?.winnerModel
      ? `winner=${params.executionTrace.winnerModel}${thinking ? ` 🧠 ${thinking}` : ""}`
      : undefined,
    typeof params.executionTrace?.fallbackUsed === "boolean"
      ? `fallback=${params.executionTrace.fallbackUsed ? "yes" : "no"}`
      : undefined,
    typeof params.executionTrace?.attempts?.length === "number"
      ? `attempts=${params.executionTrace.attempts.length.toLocaleString()}`
      : undefined,
    params.completion?.stopReason ? `stop=${params.completion.stopReason}` : undefined,
    (() => {
      const prompt = formatSummaryPromptValue({
        contextLimit: params.contextLimit,
        promptTokens: params.promptTokens,
      });
      return prompt ? `prompt=${prompt}` : undefined;
    })(),
    typeof params.usage?.input === "number" && params.usage.input > 0
      ? `⬇️ ${formatTokenCount(params.usage.input)}`
      : undefined,
    typeof params.usage?.output === "number" && params.usage.output > 0
      ? `⬆️ ${formatTokenCount(params.usage.output)}`
      : undefined,
    typeof params.usage?.cacheRead === "number" && params.usage.cacheRead > 0
      ? `♻️ ${formatTokenCount(params.usage.cacheRead)}`
      : undefined,
    typeof params.usage?.cacheWrite === "number" && params.usage.cacheWrite > 0
      ? `🆕 ${formatTokenCount(params.usage.cacheWrite)}`
      : undefined,
    typeof params.usage?.total === "number" && params.usage.total > 0
      ? `🔢 ${formatTokenCount(params.usage.total)}`
      : undefined,
    typeof params.toolSummary?.calls === "number" && params.toolSummary.calls > 0
      ? `tools=${params.toolSummary.calls.toLocaleString()}`
      : undefined,
    typeof params.contextManagement?.lastTurnCompactions === "number" &&
    params.contextManagement.lastTurnCompactions > 0
      ? `compactions=${params.contextManagement.lastTurnCompactions.toLocaleString()}`
      : undefined,
  ].filter((value): value is string => Boolean(value));
  return fields.length > 0 ? `Summary: ${fields.join(" ")}` : undefined;
}

function buildInlineRawTracePayload(params: {
  entry: SessionEntry | undefined;
  rawUserText?: string;
  rawAssistantText?: string;
  sessionUsage?: {
    input?: number;
    output?: number;
    cacheRead?: number;
    cacheWrite?: number;
    total?: number;
  };
  usage?: {
    input?: number;
    output?: number;
    cacheRead?: number;
    cacheWrite?: number;
    total?: number;
  };
  lastCallUsage?: {
    input?: number;
    output?: number;
    cacheRead?: number;
    cacheWrite?: number;
    total?: number;
  };
  provider?: string;
  model?: string;
  contextLimit?: number;
  promptTokens?: number;
  executionTrace?: TraceExecutionView;
  requestShaping?: {
    authMode?: string;
    thinking?: string;
    reasoning?: string;
    verbose?: string;
    trace?: string;
    fallbackEligible?: boolean;
    blockStreaming?: string;
  };
  promptSegments?: TracePromptSegmentView[];
  toolSummary?: TraceToolSummaryView;
  completion?: TraceCompletionView;
  contextManagement?: TraceContextManagementView;
}): ReplyPayload | undefined {
  if (params.entry?.traceLevel !== "raw") {
    return undefined;
  }
  const resolvedPromptTokens = resolveRequestPromptTokens({
    lastCallUsage: params.lastCallUsage,
    promptTokens: params.promptTokens,
    usage: params.usage,
  });
  const requestContextBlock = formatRequestContextTraceBlock({
    provider: params.provider,
    model: params.model,
    contextLimit: params.contextLimit,
    promptTokens: resolvedPromptTokens,
  });
  const usageBlocks = [
    formatUsageTraceBlock("Usage (Session Total)", params.sessionUsage),
    formatUsageTraceBlock("Usage (Last Turn Total)", params.usage),
    requestContextBlock,
    formatExecutionResultTraceBlock(params.executionTrace),
    formatFallbackChainTraceBlock(params.executionTrace),
    formatKeyValueTraceBlock("Request Shaping", [
      ["provider", params.provider],
      ["model", params.model],
      ["auth", params.requestShaping?.authMode],
      ["thinking", params.requestShaping?.thinking],
      ["reasoning", params.requestShaping?.reasoning],
      ["verbose", params.requestShaping?.verbose],
      ["trace", params.requestShaping?.trace],
      ["fallbackEligible", params.requestShaping?.fallbackEligible],
      ["blockStreaming", params.requestShaping?.blockStreaming],
    ]),
    formatPromptSegmentsTraceBlock(params.promptSegments, params.rawUserText),
    formatToolSummaryTraceBlock(params.toolSummary),
    formatCompletionTraceBlock(params.completion),
    formatContextManagementTraceBlock(params.contextManagement),
  ].filter((value): value is string => Boolean(value));
  return {
    text: [
      ...usageBlocks,
      formatRawTraceBlock("Model Input (User Role)", params.rawUserText),
      formatRawTraceBlock("Model Output (Assistant Role)", params.rawAssistantText),
      formatRawTraceSummaryLine({
        executionTrace: params.executionTrace,
        completion: params.completion,
        contextLimit: params.contextLimit,
        promptTokens: resolvedPromptTokens,
        usage: params.usage,
        toolSummary: params.toolSummary,
        contextManagement: params.contextManagement,
        requestShaping: params.requestShaping,
      }),
    ].join("\n\n\n"),
  };
}

function refreshSessionEntryFromStore(params: {
  storePath?: string;
  sessionKey?: string;
  fallbackEntry?: SessionEntry;
  activeSessionStore?: Record<string, SessionEntry>;
}): SessionEntry | undefined {
  const { storePath, sessionKey, fallbackEntry, activeSessionStore } = params;
  if (!storePath || !sessionKey) {
    return fallbackEntry;
  }
  try {
    const latestStore = loadSessionStore(storePath, { skipCache: true });
    const latestEntry = latestStore?.[sessionKey];
    if (!latestEntry) {
      return fallbackEntry;
    }
    if (activeSessionStore) {
      activeSessionStore[sessionKey] = latestEntry;
    }
    return latestEntry;
  } catch {
    return fallbackEntry;
  }
}

export async function runReplyAgent(params: {
  commandBody: string;
  followupRun: FollowupRun;
  queueKey: string;
  resolvedQueue: QueueSettings;
  shouldSteer: boolean;
  shouldFollowup: boolean;
  isActive: boolean;
  isRunActive?: () => boolean;
  isStreaming: boolean;
  opts?: GetReplyOptions;
  typing: TypingController;
  sessionEntry?: SessionEntry;
  sessionStore?: Record<string, SessionEntry>;
  sessionKey?: string;
  storePath?: string;
  defaultModel: string;
  agentCfgContextTokens?: number;
  resolvedVerboseLevel: VerboseLevel;
  isNewSession: boolean;
  blockStreamingEnabled: boolean;
  blockReplyChunking?: {
    minChars: number;
    maxChars: number;
    breakPreference: "paragraph" | "newline" | "sentence";
    flushOnParagraph?: boolean;
  };
  resolvedBlockStreamingBreak: "text_end" | "message_end";
  sessionCtx: TemplateContext;
  shouldInjectGroupIntro: boolean;
  typingMode: TypingMode;
  resetTriggered?: boolean;
  replyOperation?: ReplyOperation;
}): Promise<ReplyPayload | ReplyPayload[] | undefined> {
  const {
    commandBody,
    followupRun,
    queueKey,
    resolvedQueue,
    shouldSteer,
    shouldFollowup,
    isActive,
    isRunActive,
    isStreaming,
    opts,
    typing,
    sessionEntry,
    sessionStore,
    sessionKey,
    storePath,
    defaultModel,
    agentCfgContextTokens,
    resolvedVerboseLevel,
    isNewSession,
    blockStreamingEnabled,
    blockReplyChunking,
    resolvedBlockStreamingBreak,
    sessionCtx,
    shouldInjectGroupIntro,
    typingMode,
    resetTriggered,
    replyOperation: providedReplyOperation,
  } = params;

  let activeSessionEntry = sessionEntry;
  const activeSessionStore = sessionStore;
  let activeIsNewSession = isNewSession;

  const isHeartbeat = opts?.isHeartbeat === true;
  const typingSignals = createTypingSignaler({
    typing,
    mode: typingMode,
    isHeartbeat,
  });

  const shouldEmitToolResult = createShouldEmitToolResult({
    sessionKey,
    storePath,
    resolvedVerboseLevel,
  });
  const shouldEmitToolOutput = createShouldEmitToolOutput({
    sessionKey,
    storePath,
    resolvedVerboseLevel,
  });

  const pendingToolTasks = new Set<Promise<void>>();
  const blockReplyTimeoutMs = opts?.blockReplyTimeoutMs ?? BLOCK_REPLY_SEND_TIMEOUT_MS;
  const touchActiveSessionEntry = async () => {
    if (!activeSessionEntry || !activeSessionStore || !sessionKey) {
      return;
    }
    const updatedAt = Date.now();
    activeSessionEntry.updatedAt = updatedAt;
    activeSessionStore[sessionKey] = activeSessionEntry;
    if (storePath) {
      await updateSessionStoreEntry({
        storePath,
        sessionKey,
        update: async () => ({ updatedAt }),
      });
    }
  };

  if (shouldSteer && isStreaming) {
    const steerSessionId =
      (sessionKey ? replyRunRegistry.resolveSessionId(sessionKey) : undefined) ??
      followupRun.run.sessionId;
    const steered = queueEmbeddedPiMessage(steerSessionId, followupRun.prompt);
    if (steered && !shouldFollowup) {
      await touchActiveSessionEntry();
      typing.cleanup();
      return undefined;
    }
  }

  const activeRunQueueAction = resolveActiveRunQueueAction({
    isActive,
    isHeartbeat,
    shouldFollowup,
    queueMode: resolvedQueue.mode,
  });

  const queuedRunFollowupTurn = createFollowupRunner({
    opts,
    typing,
    typingMode,
    sessionEntry: activeSessionEntry,
    sessionStore: activeSessionStore,
    sessionKey,
    storePath,
    defaultModel,
    agentCfgContextTokens,
  });

  if (activeRunQueueAction === "drop") {
    typing.cleanup();
    return undefined;
  }

  if (activeRunQueueAction === "enqueue-followup") {
    enqueueFollowupRun(
      queueKey,
      followupRun,
      resolvedQueue,
      "message-id",
      queuedRunFollowupTurn,
      false,
    );
    // Re-check liveness after enqueue so a stale active snapshot cannot leave
    // the followup queue idle if the original run already finished.
    if (!isRunActive?.()) {
      finalizeWithFollowup(undefined, queueKey, queuedRunFollowupTurn);
    }
    await touchActiveSessionEntry();
    typing.cleanup();
    return undefined;
  }

  followupRun.run.config = await resolveQueuedReplyExecutionConfig(followupRun.run.config, {
    originatingChannel: sessionCtx.OriginatingChannel,
    messageProvider: followupRun.run.messageProvider,
    originatingAccountId: followupRun.originatingAccountId,
    agentAccountId: followupRun.run.agentAccountId,
  });

  const replyToChannel = resolveOriginMessageProvider({
    originatingChannel: sessionCtx.OriginatingChannel,
    provider: sessionCtx.Surface ?? sessionCtx.Provider,
  }) as OriginatingChannelType | undefined;
  const replyToMode = resolveReplyToMode(
    followupRun.run.config,
    replyToChannel,
    sessionCtx.AccountId,
    sessionCtx.ChatType,
  );
  const applyReplyToMode = createReplyToModeFilterForChannel(replyToMode, replyToChannel);
  const cfg = followupRun.run.config;
  const normalizeReplyMediaPaths = createReplyMediaPathNormalizer({
    cfg,
    sessionKey,
    workspaceDir: followupRun.run.workspaceDir,
    messageProvider: followupRun.run.messageProvider,
    accountId: followupRun.originatingAccountId ?? followupRun.run.agentAccountId,
    groupId: followupRun.run.groupId,
    groupChannel: followupRun.run.groupChannel,
    groupSpace: followupRun.run.groupSpace,
    requesterSenderId: followupRun.run.senderId,
    requesterSenderName: followupRun.run.senderName,
    requesterSenderUsername: followupRun.run.senderUsername,
    requesterSenderE164: followupRun.run.senderE164,
  });
  const blockReplyCoalescing =
    blockStreamingEnabled && opts?.onBlockReply
      ? resolveEffectiveBlockStreamingConfig({
          cfg,
          provider: sessionCtx.Provider,
          accountId: sessionCtx.AccountId,
          chunking: blockReplyChunking,
        }).coalescing
      : undefined;
  const blockReplyPipeline =
    blockStreamingEnabled && opts?.onBlockReply
      ? createBlockReplyPipeline({
          onBlockReply: opts.onBlockReply,
          timeoutMs: blockReplyTimeoutMs,
          coalescing: blockReplyCoalescing,
          buffer: createAudioAsVoiceBuffer({ isAudioPayload }),
        })
      : null;

  const replySessionKey = sessionKey ?? followupRun.run.sessionKey;
  let replyOperation: ReplyOperation;
  try {
    replyOperation =
      providedReplyOperation ??
      createReplyOperation({
        sessionId: followupRun.run.sessionId,
        sessionKey: replySessionKey ?? "",
        resetTriggered: resetTriggered === true,
        upstreamAbortSignal: opts?.abortSignal,
      });
  } catch (error) {
    if (error instanceof ReplyRunAlreadyActiveError) {
      typing.cleanup();
      return {
        text: "⚠️ Previous run is still shutting down. Please try again in a moment.",
      };
    }
    throw error;
  }
  let runFollowupTurn = queuedRunFollowupTurn;
  const prePreflightCompactionCount = activeSessionEntry?.compactionCount ?? 0;
  let preflightCompactionApplied = false;

  try {
    await typingSignals.signalRunStart();

    activeSessionEntry = await runPreflightCompactionIfNeeded({
      cfg,
      followupRun,
      promptForEstimate: followupRun.prompt,
      defaultModel,
      agentCfgContextTokens,
      sessionEntry: activeSessionEntry,
      sessionStore: activeSessionStore,
      sessionKey,
      storePath,
      isHeartbeat,
      replyOperation,
    });
    preflightCompactionApplied =
      (activeSessionEntry?.compactionCount ?? 0) > prePreflightCompactionCount;

    activeSessionEntry = await runMemoryFlushIfNeeded({
      cfg,
      followupRun,
      promptForEstimate: followupRun.prompt,
      sessionCtx,
      opts,
      defaultModel,
      agentCfgContextTokens,
      resolvedVerboseLevel,
      sessionEntry: activeSessionEntry,
      sessionStore: activeSessionStore,
      sessionKey,
      storePath,
      isHeartbeat,
      replyOperation,
    });

    runFollowupTurn = createFollowupRunner({
      opts,
      typing,
      typingMode,
      sessionEntry: activeSessionEntry,
      sessionStore: activeSessionStore,
      sessionKey,
      storePath,
      defaultModel,
      agentCfgContextTokens,
    });

    let responseUsageLine: string | undefined;
    type SessionResetOptions = {
      failureLabel: string;
      buildLogMessage: (nextSessionId: string) => string;
      cleanupTranscripts?: boolean;
    };
    const resetSession = async ({
      failureLabel,
      buildLogMessage,
      cleanupTranscripts,
    }: SessionResetOptions): Promise<boolean> =>
      await resetReplyRunSession({
        options: {
          failureLabel,
          buildLogMessage,
          cleanupTranscripts,
        },
        sessionKey,
        queueKey,
        activeSessionEntry,
        activeSessionStore,
        storePath,
        messageThreadId:
          typeof sessionCtx.MessageThreadId === "string" ? sessionCtx.MessageThreadId : undefined,
        followupRun,
        onActiveSessionEntry: (nextEntry) => {
          activeSessionEntry = nextEntry;
        },
        onNewSession: () => {
          activeIsNewSession = true;
        },
      });
    const resetSessionAfterCompactionFailure = async (reason: string): Promise<boolean> =>
      resetSession({
        failureLabel: "compaction failure",
        buildLogMessage: (nextSessionId) =>
          `Auto-compaction failed (${reason}). Restarting session ${sessionKey} -> ${nextSessionId} and retrying.`,
      });
    const resetSessionAfterRoleOrderingConflict = async (reason: string): Promise<boolean> =>
      resetSession({
        failureLabel: "role ordering conflict",
        buildLogMessage: (nextSessionId) =>
          `Role ordering conflict (${reason}). Restarting session ${sessionKey} -> ${nextSessionId}.`,
        cleanupTranscripts: true,
      });

    replyOperation.setPhase("running");
    const runStartedAt = Date.now();
    const runOutcome = await runAgentTurnWithFallback({
      commandBody,
      followupRun,
      sessionCtx,
      replyOperation,
      opts,
      typingSignals,
      blockReplyPipeline,
      blockStreamingEnabled,
      blockReplyChunking,
      resolvedBlockStreamingBreak,
      applyReplyToMode,
      shouldEmitToolResult,
      shouldEmitToolOutput,
      pendingToolTasks,
      resetSessionAfterCompactionFailure,
      resetSessionAfterRoleOrderingConflict,
      isHeartbeat,
      sessionKey,
      getActiveSessionEntry: () => activeSessionEntry,
      activeSessionStore,
      storePath,
      resolvedVerboseLevel,
    });

    if (runOutcome.kind === "final") {
      if (!replyOperation.result) {
        replyOperation.fail("run_failed", new Error("reply operation exited with final payload"));
      }
      return finalizeWithFollowup(runOutcome.payload, queueKey, runFollowupTurn);
    }

    const {
      runId,
      runResult,
      fallbackProvider,
      fallbackModel,
      fallbackAttempts,
      directlySentBlockKeys,
    } = runOutcome;
    let { didLogHeartbeatStrip, autoCompactionCount } = runOutcome;

    if (
      shouldInjectGroupIntro &&
      activeSessionEntry &&
      activeSessionStore &&
      sessionKey &&
      activeSessionEntry.groupActivationNeedsSystemIntro
    ) {
      const updatedAt = Date.now();
      activeSessionEntry.groupActivationNeedsSystemIntro = false;
      activeSessionEntry.updatedAt = updatedAt;
      activeSessionStore[sessionKey] = activeSessionEntry;
      if (storePath) {
        await updateSessionStoreEntry({
          storePath,
          sessionKey,
          update: async () => ({
            groupActivationNeedsSystemIntro: false,
            updatedAt,
          }),
        });
      }
    }

    const payloadArray = runResult.payloads ?? [];

    if (blockReplyPipeline) {
      await blockReplyPipeline.flush({ force: true });
      blockReplyPipeline.stop();
    }
    if (pendingToolTasks.size > 0) {
      await Promise.allSettled(pendingToolTasks);
    }

    const usage = runResult.meta?.agentMeta?.usage;
    const promptTokens = runResult.meta?.agentMeta?.promptTokens;
    const modelUsed = runResult.meta?.agentMeta?.model ?? fallbackModel ?? defaultModel;
    const providerUsed =
      runResult.meta?.agentMeta?.provider ?? fallbackProvider ?? followupRun.run.provider;
    const verboseEnabled = resolvedVerboseLevel !== "off";
    const selectedProvider = followupRun.run.provider;
    const selectedModel = followupRun.run.model;
    const fallbackStateEntry =
      activeSessionEntry ?? (sessionKey ? activeSessionStore?.[sessionKey] : undefined);
    const fallbackTransition = resolveFallbackTransition({
      selectedProvider,
      selectedModel,
      activeProvider: providerUsed,
      activeModel: modelUsed,
      attempts: fallbackAttempts,
      state: fallbackStateEntry,
    });
    if (fallbackTransition.stateChanged) {
      if (fallbackStateEntry) {
        fallbackStateEntry.fallbackNoticeSelectedModel = fallbackTransition.nextState.selectedModel;
        fallbackStateEntry.fallbackNoticeActiveModel = fallbackTransition.nextState.activeModel;
        fallbackStateEntry.fallbackNoticeReason = fallbackTransition.nextState.reason;
        fallbackStateEntry.updatedAt = Date.now();
        activeSessionEntry = fallbackStateEntry;
      }
      if (sessionKey && fallbackStateEntry && activeSessionStore) {
        activeSessionStore[sessionKey] = fallbackStateEntry;
      }
      if (sessionKey && storePath) {
        await updateSessionStoreEntry({
          storePath,
          sessionKey,
          update: async () => ({
            fallbackNoticeSelectedModel: fallbackTransition.nextState.selectedModel,
            fallbackNoticeActiveModel: fallbackTransition.nextState.activeModel,
            fallbackNoticeReason: fallbackTransition.nextState.reason,
          }),
        });
      }
    }
    const cliSessionId = isCliProvider(providerUsed, cfg)
      ? normalizeOptionalString(runResult.meta?.agentMeta?.sessionId)
      : undefined;
    const cliSessionBinding = isCliProvider(providerUsed, cfg)
      ? runResult.meta?.agentMeta?.cliSessionBinding
      : undefined;
    const contextTokensUsed =
      resolveContextTokensForModel({
        cfg,
        provider: providerUsed,
        model: modelUsed,
        contextTokensOverride: agentCfgContextTokens,
        fallbackContextTokens: activeSessionEntry?.contextTokens ?? DEFAULT_CONTEXT_TOKENS,
        allowAsyncLoad: false,
      }) ?? DEFAULT_CONTEXT_TOKENS;

    await persistRunSessionUsage({
      storePath,
      sessionKey,
      cfg,
      usage,
      lastCallUsage: runResult.meta?.agentMeta?.lastCallUsage,
      promptTokens,
      modelUsed,
      providerUsed,
      contextTokensUsed,
      systemPromptReport: runResult.meta?.systemPromptReport,
      cliSessionId,
      cliSessionBinding,
      usageIsContextSnapshot: isCliProvider(providerUsed, cfg),
    });

    // Drain any late tool/block deliveries before deciding there's "nothing to send".
    // Otherwise, a late typing trigger (e.g. from a tool callback) can outlive the run and
    // keep the typing indicator stuck.
    if (payloadArray.length === 0) {
      return finalizeWithFollowup(undefined, queueKey, runFollowupTurn);
    }

    const payloadResult = await buildReplyPayloads({
      payloads: payloadArray,
      isHeartbeat,
      didLogHeartbeatStrip,
      silentExpected: followupRun.run.silentExpected,
      blockStreamingEnabled,
      blockReplyPipeline,
      directlySentBlockKeys,
      replyToMode,
      replyToChannel,
      currentMessageId: sessionCtx.MessageSidFull ?? sessionCtx.MessageSid,
      replyThreading: sessionCtx.ReplyThreading,
      messageProvider: followupRun.run.messageProvider,
      messagingToolSentTexts: runResult.messagingToolSentTexts,
      messagingToolSentMediaUrls: runResult.messagingToolSentMediaUrls,
      messagingToolSentTargets: runResult.messagingToolSentTargets,
      originatingChannel: sessionCtx.OriginatingChannel,
      originatingTo: resolveOriginMessageTo({
        originatingTo: sessionCtx.OriginatingTo,
        to: sessionCtx.To,
      }),
      accountId: sessionCtx.AccountId,
      normalizeMediaPaths: normalizeReplyMediaPaths,
    });
    const { replyPayloads } = payloadResult;
    didLogHeartbeatStrip = payloadResult.didLogHeartbeatStrip;

    if (replyPayloads.length === 0) {
      return finalizeWithFollowup(undefined, queueKey, runFollowupTurn);
    }

    const successfulCronAdds = runResult.successfulCronAdds ?? 0;
    const hasReminderCommitment = replyPayloads.some(
      (payload) =>
        !payload.isError &&
        typeof payload.text === "string" &&
        hasUnbackedReminderCommitment(payload.text),
    );
    // Suppress the guard note when an existing cron job (created in a prior
    // turn) already covers the commitment — avoids false positives (#32228).
    const coveredByExistingCron =
      hasReminderCommitment && successfulCronAdds === 0
        ? await hasSessionRelatedCronJobs({
            cronStorePath: cfg.cron?.store,
            sessionKey,
          })
        : false;
    const guardedReplyPayloads =
      hasReminderCommitment && successfulCronAdds === 0 && !coveredByExistingCron
        ? appendUnscheduledReminderNote(replyPayloads)
        : replyPayloads;

    await signalTypingIfNeeded(guardedReplyPayloads, typingSignals);

    if (isDiagnosticsEnabled(cfg) && hasNonzeroUsage(usage)) {
      const input = usage.input ?? 0;
      const output = usage.output ?? 0;
      const cacheRead = usage.cacheRead ?? 0;
      const cacheWrite = usage.cacheWrite ?? 0;
      const promptTokens = input + cacheRead + cacheWrite;
      const totalTokens = usage.total ?? promptTokens + output;
      const costConfig = resolveModelCostConfig({
        provider: providerUsed,
        model: modelUsed,
        config: cfg,
      });
      const costUsd = estimateUsageCost({ usage, cost: costConfig });
      emitDiagnosticEvent({
        type: "model.usage",
        sessionKey,
        sessionId: followupRun.run.sessionId,
        channel: replyToChannel,
        provider: providerUsed,
        model: modelUsed,
        usage: {
          input,
          output,
          cacheRead,
          cacheWrite,
          promptTokens,
          total: totalTokens,
        },
        lastCallUsage: runResult.meta?.agentMeta?.lastCallUsage,
        context: {
          limit: contextTokensUsed,
          used: totalTokens,
        },
        costUsd,
        durationMs: Date.now() - runStartedAt,
      });
    }

    const responseUsageRaw =
      activeSessionEntry?.responseUsage ??
      (sessionKey ? activeSessionStore?.[sessionKey]?.responseUsage : undefined);
    const responseUsageMode = resolveResponseUsageMode(responseUsageRaw);
    if (responseUsageMode !== "off" && hasNonzeroUsage(usage)) {
      const authMode = resolveModelAuthMode(providerUsed, cfg);
      const showCost = authMode === "api-key";
      const costConfig = showCost
        ? resolveModelCostConfig({
            provider: providerUsed,
            model: modelUsed,
            config: cfg,
          })
        : undefined;
      let formatted = formatResponseUsageLine({
        usage,
        showCost,
        costConfig,
      });
      if (formatted && responseUsageMode === "full" && sessionKey) {
        formatted = `${formatted} · session \`${sessionKey}\``;
      }
      if (formatted) {
        responseUsageLine = formatted;
      }
    }

    if (verboseEnabled) {
      activeSessionEntry = refreshSessionEntryFromStore({
        storePath,
        sessionKey,
        fallbackEntry: activeSessionEntry,
        activeSessionStore,
      });
    }

    // If verbose is enabled, prepend operational run notices.
    let finalPayloads = guardedReplyPayloads;
    const verboseNotices: ReplyPayload[] = [];

    if (verboseEnabled && activeIsNewSession) {
      verboseNotices.push({ text: `🧭 New session: ${followupRun.run.sessionId}` });
    }

    if (fallbackTransition.fallbackTransitioned) {
      emitAgentEvent({
        runId,
        sessionKey,
        stream: "lifecycle",
        data: {
          phase: "fallback",
          selectedProvider,
          selectedModel,
          activeProvider: providerUsed,
          activeModel: modelUsed,
          reasonSummary: fallbackTransition.reasonSummary,
          attemptSummaries: fallbackTransition.attemptSummaries,
          attempts: fallbackAttempts,
        },
      });
      if (verboseEnabled) {
        const fallbackNotice = buildFallbackNotice({
          selectedProvider,
          selectedModel,
          activeProvider: providerUsed,
          activeModel: modelUsed,
          attempts: fallbackAttempts,
        });
        if (fallbackNotice) {
          verboseNotices.push({ text: fallbackNotice });
        }
      }
    }
    if (fallbackTransition.fallbackCleared) {
      emitAgentEvent({
        runId,
        sessionKey,
        stream: "lifecycle",
        data: {
          phase: "fallback_cleared",
          selectedProvider,
          selectedModel,
          activeProvider: providerUsed,
          activeModel: modelUsed,
          previousActiveModel: fallbackTransition.previousState.activeModel,
        },
      });
      if (verboseEnabled) {
        verboseNotices.push({
          text: buildFallbackClearedNotice({
            selectedProvider,
            selectedModel,
            previousActiveModel: fallbackTransition.previousState.activeModel,
          }),
        });
      }
    }

    if (autoCompactionCount > 0) {
      const previousSessionId = activeSessionEntry?.sessionId ?? followupRun.run.sessionId;
      const count = await incrementRunCompactionCount({
        cfg,
        sessionEntry: activeSessionEntry,
        sessionStore: activeSessionStore,
        sessionKey,
        storePath,
        amount: autoCompactionCount,
        lastCallUsage: runResult.meta?.agentMeta?.lastCallUsage,
        contextTokensUsed,
        newSessionId: runResult.meta?.agentMeta?.sessionId,
      });
      const refreshedSessionEntry =
        sessionKey && activeSessionStore ? activeSessionStore[sessionKey] : undefined;
      if (refreshedSessionEntry) {
        activeSessionEntry = refreshedSessionEntry;
        refreshQueuedFollowupSession({
          key: queueKey,
          previousSessionId,
          nextSessionId: refreshedSessionEntry.sessionId,
          nextSessionFile: refreshedSessionEntry.sessionFile,
        });
      }

      // Inject post-compaction workspace context for the next agent turn
      if (sessionKey) {
        const workspaceDir = process.cwd();
        readPostCompactionContext(workspaceDir, {
          cfg,
          agentId: resolveSessionAgentId({ sessionKey, config: cfg }),
        })
          .then((contextContent) => {
            if (contextContent) {
              enqueueSystemEvent(contextContent, { sessionKey });
            }
          })
          .catch(() => {
            // Silent failure — post-compaction context is best-effort
          });
      }

      if (verboseEnabled) {
        const suffix = typeof count === "number" ? ` (count ${count})` : "";
        verboseNotices.push({ text: `🧹 Auto-compaction complete${suffix}.` });
      }
    }
    const prefixPayloads = [...verboseNotices];
    const rawUserText =
      runResult.meta?.finalPromptText ??
      sessionCtx.CommandBody ??
      sessionCtx.RawBody ??
      sessionCtx.BodyForAgent ??
      sessionCtx.Body;
    const rawAssistantText =
      runResult.meta?.finalAssistantRawText ?? runResult.meta?.finalAssistantVisibleText;
    const traceAuthorized = followupRun.run.traceAuthorized === true;
    const executionTrace = mergeExecutionTrace({
      fallbackAttempts,
      executionTrace: runResult.meta?.executionTrace as TraceExecutionView | undefined,
      provider: providerUsed,
      model: modelUsed,
      runner: isCliProvider(providerUsed, cfg) ? "cli" : "embedded",
    });
    const requestShaping = {
      authMode:
        runResult.meta?.requestShaping?.authMode ??
        (cfg?.models?.providers && providerUsed in cfg.models.providers
          ? (resolveModelAuthMode(providerUsed, cfg) ?? undefined)
          : undefined),
      thinking:
        runResult.meta?.requestShaping?.thinking ??
        normalizeOptionalString(followupRun.run.thinkLevel),
      reasoning:
        runResult.meta?.requestShaping?.reasoning ??
        normalizeOptionalString(followupRun.run.reasoningLevel),
      verbose:
        runResult.meta?.requestShaping?.verbose ?? normalizeOptionalString(resolvedVerboseLevel),
      trace:
        runResult.meta?.requestShaping?.trace ??
        normalizeOptionalString(activeSessionEntry?.traceLevel),
      fallbackEligible:
        runResult.meta?.requestShaping?.fallbackEligible ??
        hasConfiguredModelFallbacks({
          cfg,
          agentId: followupRun.run.agentId,
          sessionKey: followupRun.run.sessionKey,
        }),
      blockStreaming:
        runResult.meta?.requestShaping?.blockStreaming ??
        normalizeOptionalString(resolvedBlockStreamingBreak),
    };
    const promptSegments =
      (runResult.meta?.promptSegments as TracePromptSegmentView[] | undefined) ??
      derivePromptSegments(rawUserText);
    const toolSummary = runResult.meta?.toolSummary as TraceToolSummaryView | undefined;
    const completion =
      (runResult.meta?.completion as TraceCompletionView | undefined) ??
      (runResult.meta?.stopReason
        ? {
            stopReason: runResult.meta.stopReason,
            finishReason: runResult.meta.stopReason,
            ...(runResult.meta.stopReason.toLowerCase().includes("refusal")
              ? { refusal: true }
              : {}),
          }
        : undefined);
    const contextManagement = {
      ...(typeof activeSessionEntry?.compactionCount === "number"
        ? { sessionCompactions: activeSessionEntry.compactionCount }
        : {}),
      ...(typeof runResult.meta?.contextManagement?.lastTurnCompactions === "number"
        ? { lastTurnCompactions: runResult.meta.contextManagement.lastTurnCompactions }
        : typeof runResult.meta?.agentMeta?.compactionCount === "number"
          ? { lastTurnCompactions: runResult.meta.agentMeta.compactionCount }
          : {}),
      ...(runResult.meta?.contextManagement &&
      typeof runResult.meta.contextManagement.preflightCompactionApplied === "boolean"
        ? {
            preflightCompactionApplied: runResult.meta.contextManagement.preflightCompactionApplied,
          }
        : preflightCompactionApplied
          ? { preflightCompactionApplied }
          : {}),
      ...(runResult.meta?.contextManagement &&
      typeof runResult.meta.contextManagement.postCompactionContextInjected === "boolean"
        ? {
            postCompactionContextInjected:
              runResult.meta.contextManagement.postCompactionContextInjected,
          }
        : {}),
    } satisfies TraceContextManagementView;
    const sessionUsage =
      traceAuthorized && activeSessionEntry?.traceLevel === "raw"
        ? await accumulateSessionUsageFromTranscript({
            sessionId: runResult.meta?.agentMeta?.sessionId ?? followupRun.run.sessionId,
            storePath,
            sessionFile: followupRun.run.sessionFile,
          })
        : undefined;
    const traceEnabledForSender =
      traceAuthorized &&
      (activeSessionEntry?.traceLevel === "on" || activeSessionEntry?.traceLevel === "raw");
    const shouldAppendTracePayload = verboseEnabled || traceEnabledForSender;
    let trailingPluginStatusPayload: ReplyPayload | undefined;
    if (shouldAppendTracePayload) {
      const pluginStatusPayload = buildInlinePluginStatusPayload({
        entry: activeSessionEntry,
        includeTraceLines: traceEnabledForSender,
      });
      const rawTracePayload =
        traceAuthorized && activeSessionEntry?.traceLevel === "raw"
          ? buildInlineRawTracePayload({
              entry: activeSessionEntry,
              rawUserText,
              rawAssistantText,
              sessionUsage,
              usage: runResult.meta?.agentMeta?.usage,
              lastCallUsage: runResult.meta?.agentMeta?.lastCallUsage,
              provider: providerUsed,
              model: modelUsed,
              contextLimit: contextTokensUsed,
              promptTokens,
              executionTrace,
              requestShaping,
              promptSegments,
              toolSummary,
              completion,
              contextManagement,
            })
          : undefined;
      trailingPluginStatusPayload =
        pluginStatusPayload && rawTracePayload
          ? { text: `${pluginStatusPayload.text}\n\n${rawTracePayload.text}` }
          : (pluginStatusPayload ?? rawTracePayload);
    }
    if (prefixPayloads.length > 0) {
      finalPayloads = [...prefixPayloads, ...finalPayloads];
    }
    if (trailingPluginStatusPayload) {
      finalPayloads = [...finalPayloads, trailingPluginStatusPayload];
    }
    if (responseUsageLine) {
      finalPayloads = appendUsageLine(finalPayloads, responseUsageLine);
    }

    return finalizeWithFollowup(
      finalPayloads.length === 1 ? finalPayloads[0] : finalPayloads,
      queueKey,
      runFollowupTurn,
    );
  } catch (error) {
    if (
      replyOperation.result?.kind === "aborted" &&
      replyOperation.result.code === "aborted_for_restart"
    ) {
      return finalizeWithFollowup(
        { text: "⚠️ Gateway is restarting. Please wait a few seconds and try again." },
        queueKey,
        runFollowupTurn,
      );
    }
    if (replyOperation.result?.kind === "aborted") {
      return finalizeWithFollowup({ text: SILENT_REPLY_TOKEN }, queueKey, runFollowupTurn);
    }
    if (error instanceof GatewayDrainingError) {
      replyOperation.fail("gateway_draining", error);
      return finalizeWithFollowup(
        { text: "⚠️ Gateway is restarting. Please wait a few seconds and try again." },
        queueKey,
        runFollowupTurn,
      );
    }
    if (error instanceof CommandLaneClearedError) {
      replyOperation.fail("command_lane_cleared", error);
      return finalizeWithFollowup(
        { text: "⚠️ Gateway is restarting. Please wait a few seconds and try again." },
        queueKey,
        runFollowupTurn,
      );
    }
    replyOperation.fail("run_failed", error);
    // Keep the followup queue moving even when an unexpected exception escapes
    // the run path; the caller still receives the original error.
    finalizeWithFollowup(undefined, queueKey, runFollowupTurn);
    throw error;
  } finally {
    replyOperation.complete();
    blockReplyPipeline?.stop();
    typing.markRunComplete();
    // Safety net: the dispatcher's onIdle callback normally fires
    // markDispatchIdle(), but if the dispatcher exits early, errors,
    // or the reply path doesn't go through it cleanly, the second
    // signal never fires and the typing keepalive loop runs forever.
    // Calling this twice is harmless — cleanup() is guarded by the
    // `active` flag.  Same pattern as the followup runner fix (#26881).
    typing.markDispatchIdle();
  }
}