import type { OpenClawConfig } from "../config/config.js";
import { createSubsystemLogger } from "../logging/subsystem.js";
import {
  createFlowForTask,
  createFlowRecord,
  deleteFlowRecordById,
  getFlowById,
  updateFlowRecordById,
} from "./flow-registry.js";
import type { FlowRecord } from "./flow-registry.types.js";
import {
  cancelTaskById,
  createTaskRecord,
  findLatestTaskForFlowId,
  linkTaskToFlowById,
  listTasksForFlowId,
  markTaskLostById,
  markTaskRunningByRunId,
  markTaskTerminalByRunId,
  recordTaskProgressByRunId,
  setTaskRunDeliveryStatusByRunId,
} from "./task-registry.js";
import { summarizeTaskRecords } from "./task-registry.summary.js";
import type {
  TaskDeliveryState,
  TaskDeliveryStatus,
  TaskNotifyPolicy,
  TaskRecord,
  TaskRegistrySummary,
  TaskRuntime,
  TaskStatus,
  TaskTerminalOutcome,
} from "./task-registry.types.js";

const log = createSubsystemLogger("tasks/executor");

function isOneTaskFlowEligible(task: TaskRecord): boolean {
  if (task.parentFlowId?.trim() || !task.requesterSessionKey.trim()) {
    return false;
  }
  if (task.deliveryStatus === "not_applicable") {
    return false;
  }
  return task.runtime === "acp" || task.runtime === "subagent";
}

function ensureSingleTaskFlow(params: {
  task: TaskRecord;
  requesterOrigin?: TaskDeliveryState["requesterOrigin"];
}): TaskRecord {
  if (!isOneTaskFlowEligible(params.task)) {
    return params.task;
  }
  try {
    const flow = createFlowForTask({
      task: params.task,
      requesterOrigin: params.requesterOrigin,
    });
    const linked = linkTaskToFlowById({
      taskId: params.task.taskId,
      flowId: flow.flowId,
    });
    if (!linked) {
      deleteFlowRecordById(flow.flowId);
      return params.task;
    }
    if (linked.parentFlowId !== flow.flowId) {
      deleteFlowRecordById(flow.flowId);
      return linked;
    }
    return linked;
  } catch (error) {
    log.warn("Failed to create one-task flow for detached run", {
      taskId: params.task.taskId,
      runId: params.task.runId,
      error,
    });
    return params.task;
  }
}

export function createQueuedTaskRun(params: {
  runtime: TaskRuntime;
  sourceId?: string;
  requesterSessionKey: string;
  requesterOrigin?: TaskDeliveryState["requesterOrigin"];
  parentFlowId?: string;
  childSessionKey?: string;
  parentTaskId?: string;
  agentId?: string;
  runId?: string;
  label?: string;
  task: string;
  preferMetadata?: boolean;
  notifyPolicy?: TaskNotifyPolicy;
  deliveryStatus?: TaskDeliveryStatus;
}): TaskRecord {
  const task = createTaskRecord({
    ...params,
    status: "queued",
  });
  return ensureSingleTaskFlow({
    task,
    requesterOrigin: params.requesterOrigin,
  });
}

export function createLinearFlow(params: {
  ownerSessionKey: string;
  requesterOrigin?: TaskDeliveryState["requesterOrigin"];
  goal: string;
  notifyPolicy?: TaskNotifyPolicy;
  currentStep?: string;
  createdAt?: number;
  updatedAt?: number;
}): FlowRecord {
  return createFlowRecord({
    shape: "linear",
    ownerSessionKey: params.ownerSessionKey,
    requesterOrigin: params.requesterOrigin,
    goal: params.goal,
    notifyPolicy: params.notifyPolicy,
    currentStep: params.currentStep,
    status: "queued",
    createdAt: params.createdAt,
    updatedAt: params.updatedAt,
  });
}

export function getFlowTaskSummary(flowId: string): TaskRegistrySummary {
  return summarizeTaskRecords(listTasksForFlowId(flowId));
}

type RetryBlockedFlowResult = {
  found: boolean;
  retried: boolean;
  reason?: string;
  previousTask?: TaskRecord;
  task?: TaskRecord;
};

type RetryBlockedFlowParams = {
  flowId: string;
  sourceId?: string;
  requesterOrigin?: TaskDeliveryState["requesterOrigin"];
  childSessionKey?: string;
  agentId?: string;
  runId?: string;
  label?: string;
  task?: string;
  preferMetadata?: boolean;
  notifyPolicy?: TaskNotifyPolicy;
  deliveryStatus?: TaskDeliveryStatus;
  status: "queued" | "running";
  startedAt?: number;
  lastEventAt?: number;
  progressSummary?: string | null;
};

function resolveRetryableBlockedFlowTask(flowId: string): {
  flowFound: boolean;
  retryable: boolean;
  latestTask?: TaskRecord;
  reason?: string;
} {
  const flow = getFlowById(flowId);
  if (!flow) {
    return {
      flowFound: false,
      retryable: false,
      reason: "Flow not found.",
    };
  }
  const latestTask = findLatestTaskForFlowId(flowId);
  if (!latestTask) {
    return {
      flowFound: true,
      retryable: false,
      reason: "Flow has no retryable task.",
    };
  }
  if (flow.status !== "blocked") {
    return {
      flowFound: true,
      retryable: false,
      latestTask,
      reason: "Flow is not blocked.",
    };
  }
  if (latestTask.status !== "succeeded" || latestTask.terminalOutcome !== "blocked") {
    return {
      flowFound: true,
      retryable: false,
      latestTask,
      reason: "Latest flow task is not blocked.",
    };
  }
  return {
    flowFound: true,
    retryable: true,
    latestTask,
  };
}

function retryBlockedFlowTask(params: RetryBlockedFlowParams): RetryBlockedFlowResult {
  const resolved = resolveRetryableBlockedFlowTask(params.flowId);
  if (!resolved.retryable || !resolved.latestTask) {
    return {
      found: resolved.flowFound,
      retried: false,
      reason: resolved.reason,
    };
  }
  const flow = getFlowById(params.flowId);
  if (!flow) {
    return {
      found: false,
      retried: false,
      reason: "Flow not found.",
      previousTask: resolved.latestTask,
    };
  }
  const task = createTaskRecord({
    runtime: resolved.latestTask.runtime,
    sourceId: params.sourceId ?? resolved.latestTask.sourceId,
    requesterSessionKey: flow.ownerSessionKey,
    requesterOrigin: params.requesterOrigin ?? flow.requesterOrigin,
    parentFlowId: flow.flowId,
    childSessionKey: params.childSessionKey,
    parentTaskId: resolved.latestTask.taskId,
    agentId: params.agentId ?? resolved.latestTask.agentId,
    runId: params.runId,
    label: params.label ?? resolved.latestTask.label,
    task: params.task ?? resolved.latestTask.task,
    preferMetadata: params.preferMetadata,
    notifyPolicy: params.notifyPolicy ?? resolved.latestTask.notifyPolicy,
    deliveryStatus: params.deliveryStatus ?? "pending",
    status: params.status,
    startedAt: params.startedAt,
    lastEventAt: params.lastEventAt,
    progressSummary: params.progressSummary,
  });
  return {
    found: true,
    retried: true,
    previousTask: resolved.latestTask,
    task,
  };
}

export function retryBlockedFlowAsQueuedTaskRun(
  params: Omit<RetryBlockedFlowParams, "status" | "startedAt" | "lastEventAt" | "progressSummary">,
): RetryBlockedFlowResult {
  return retryBlockedFlowTask({
    ...params,
    status: "queued",
  });
}

export function retryBlockedFlowAsRunningTaskRun(
  params: Omit<RetryBlockedFlowParams, "status">,
): RetryBlockedFlowResult {
  return retryBlockedFlowTask({
    ...params,
    status: "running",
  });
}

type CancelFlowResult = {
  found: boolean;
  cancelled: boolean;
  reason?: string;
  flow?: FlowRecord;
  tasks?: TaskRecord[];
};

function isActiveTaskStatus(status: TaskStatus): boolean {
  return status === "queued" || status === "running";
}

function isTerminalFlowStatus(status: FlowRecord["status"]): boolean {
  return (
    status === "succeeded" || status === "failed" || status === "cancelled" || status === "lost"
  );
}

export async function cancelFlowById(params: {
  cfg: OpenClawConfig;
  flowId: string;
}): Promise<CancelFlowResult> {
  const flow = getFlowById(params.flowId);
  if (!flow) {
    return {
      found: false,
      cancelled: false,
      reason: "Flow not found.",
    };
  }
  const linkedTasks = listTasksForFlowId(flow.flowId);
  const activeTasks = linkedTasks.filter((task) => isActiveTaskStatus(task.status));
  for (const task of activeTasks) {
    await cancelTaskById({
      cfg: params.cfg,
      taskId: task.taskId,
    });
  }
  const refreshedTasks = listTasksForFlowId(flow.flowId);
  const remainingActive = refreshedTasks.filter((task) => isActiveTaskStatus(task.status));
  if (remainingActive.length > 0) {
    return {
      found: true,
      cancelled: false,
      reason: "One or more child tasks are still active.",
      flow: getFlowById(flow.flowId),
      tasks: refreshedTasks,
    };
  }
  if (isTerminalFlowStatus(flow.status)) {
    return {
      found: true,
      cancelled: false,
      reason: `Flow is already ${flow.status}.`,
      flow,
      tasks: refreshedTasks,
    };
  }
  const updatedFlow = updateFlowRecordById(flow.flowId, {
    status: "cancelled",
    blockedTaskId: null,
    blockedSummary: null,
    endedAt: Date.now(),
    updatedAt: Date.now(),
  });
  return {
    found: true,
    cancelled: true,
    flow: updatedFlow ?? getFlowById(flow.flowId),
    tasks: refreshedTasks,
  };
}

export function createRunningTaskRun(params: {
  runtime: TaskRuntime;
  sourceId?: string;
  requesterSessionKey: string;
  requesterOrigin?: TaskDeliveryState["requesterOrigin"];
  parentFlowId?: string;
  childSessionKey?: string;
  parentTaskId?: string;
  agentId?: string;
  runId?: string;
  label?: string;
  task: string;
  notifyPolicy?: TaskNotifyPolicy;
  deliveryStatus?: TaskDeliveryStatus;
  preferMetadata?: boolean;
  startedAt?: number;
  lastEventAt?: number;
  progressSummary?: string | null;
}): TaskRecord {
  const task = createTaskRecord({
    ...params,
    status: "running",
  });
  return ensureSingleTaskFlow({
    task,
    requesterOrigin: params.requesterOrigin,
  });
}

export function startTaskRunByRunId(params: {
  runId: string;
  startedAt?: number;
  lastEventAt?: number;
  progressSummary?: string | null;
  eventSummary?: string | null;
}) {
  return markTaskRunningByRunId(params);
}

export function recordTaskRunProgressByRunId(params: {
  runId: string;
  lastEventAt?: number;
  progressSummary?: string | null;
  eventSummary?: string | null;
}) {
  return recordTaskProgressByRunId(params);
}

export function completeTaskRunByRunId(params: {
  runId: string;
  endedAt: number;
  lastEventAt?: number;
  progressSummary?: string | null;
  terminalSummary?: string | null;
  terminalOutcome?: TaskTerminalOutcome | null;
}) {
  return markTaskTerminalByRunId({
    runId: params.runId,
    status: "succeeded",
    endedAt: params.endedAt,
    lastEventAt: params.lastEventAt,
    progressSummary: params.progressSummary,
    terminalSummary: params.terminalSummary,
    terminalOutcome: params.terminalOutcome,
  });
}

export function failTaskRunByRunId(params: {
  runId: string;
  status?: Extract<TaskStatus, "failed" | "timed_out" | "cancelled">;
  endedAt: number;
  lastEventAt?: number;
  error?: string;
  progressSummary?: string | null;
  terminalSummary?: string | null;
}) {
  return markTaskTerminalByRunId({
    runId: params.runId,
    status: params.status ?? "failed",
    endedAt: params.endedAt,
    lastEventAt: params.lastEventAt,
    error: params.error,
    progressSummary: params.progressSummary,
    terminalSummary: params.terminalSummary,
  });
}

export function markTaskRunLostById(params: {
  taskId: string;
  endedAt: number;
  lastEventAt?: number;
  error?: string;
  cleanupAfter?: number;
}) {
  return markTaskLostById(params);
}

export function setDetachedTaskDeliveryStatusByRunId(params: {
  runId: string;
  deliveryStatus: TaskDeliveryStatus;
}) {
  return setTaskRunDeliveryStatusByRunId(params);
}

export async function cancelDetachedTaskRunById(params: { cfg: OpenClawConfig; taskId: string }) {
  return cancelTaskById(params);
}