/**
 * ZCLAW Kernel Client (Tauri Internal)
 *
 * Client for communicating with the internal ZCLAW Kernel via Tauri commands.
 * This replaces the external ZCLAW Gateway WebSocket connection.
 *
 * Phase 5 of Intelligence Layer Migration.
 */

import { invoke } from '@tauri-apps/api/core';
import { listen, type UnlistenFn } from '@tauri-apps/api/event';
import { createLogger } from './logger';

const log = createLogger('KernelClient');

// Re-export UnlistenFn for external use
export type { UnlistenFn };

// === Types ===

export type ConnectionState = 'disconnected' | 'connecting' | 'connected' | 'reconnecting';

export interface KernelStatus {
  initialized: boolean;
  agentCount: number;
  databaseUrl: string | null;
  defaultProvider: string | null;
  defaultModel: string | null;
}

export interface AgentInfo {
  id: string;
  name: string;
  description?: string;
  state: string;
  model?: string;
  provider?: string;
}

export interface CreateAgentRequest {
  name: string;
  description?: string;
  systemPrompt?: string;
  provider?: string;
  model?: string;
  maxTokens?: number;
  temperature?: number;
}

export interface CreateAgentResponse {
  id: string;
  name: string;
  state: string;
}

export interface ChatResponse {
  content: string;
  inputTokens: number;
  outputTokens: number;
}

export interface EventCallback {
  (payload: unknown): void;
}

export interface StreamCallbacks {
  onDelta: (delta: string) => void;
  onTool?: (tool: string, input: string, output: string) => void;
  onHand?: (name: string, status: string, result?: unknown) => void;
  onComplete: (inputTokens?: number, outputTokens?: number) => void;
  onError: (error: string) => void;
}

// === Streaming Types (match Rust StreamChatEvent) ===

export interface StreamEventDelta {
  type: 'delta';
  delta: string;
}

export interface StreamEventToolStart {
  type: 'tool_start';
  name: string;
  input: unknown;
}

export interface StreamEventToolEnd {
  type: 'tool_end';
  name: string;
  output: unknown;
}

export interface StreamEventIterationStart {
  type: 'iteration_start';
  iteration: number;
  maxIterations: number;
}

export interface StreamEventComplete {
  type: 'complete';
  inputTokens: number;
  outputTokens: number;
}

export interface StreamEventError {
  type: 'error';
  message: string;
}

export interface StreamEventHandStart {
  type: 'handStart';
  name: string;
  params: unknown;
}

export interface StreamEventHandEnd {
  type: 'handEnd';
  name: string;
  result: unknown;
}

export type StreamChatEvent =
  | StreamEventDelta
  | StreamEventToolStart
  | StreamEventToolEnd
  | StreamEventIterationStart
  | StreamEventHandStart
  | StreamEventHandEnd
  | StreamEventComplete
  | StreamEventError;

export interface StreamChunkPayload {
  sessionId: string;
  event: StreamChatEvent;
}

export interface KernelConfig {
  provider?: string;
  model?: string;
  apiKey?: string;
  baseUrl?: string;
  apiProtocol?: string;  // openai, anthropic, custom
}

/**
 * Check if running in Tauri environment
 * NOTE: This checks synchronously. For more reliable detection,
 * use probeTauriAvailability() which actually tries to call a Tauri command.
 */
export function isTauriRuntime(): boolean {
  const result = typeof window !== 'undefined' && '__TAURI_INTERNALS__' in window;
  log.debug('isTauriRuntime() check:', result, 'window exists:', typeof window !== 'undefined', '__TAURI_INTERNALS__ exists:', typeof window !== 'undefined' && '__TAURI_INTERNALS__' in window);
  return result;
}

/**
 * Probe if Tauri is actually available by trying to invoke a command.
 * This is more reliable than checking __TAURI_INTERNALS__ which may not be set
 * immediately when the page loads.
 */
let _tauriAvailable: boolean | null = null;

export async function probeTauriAvailability(): Promise<boolean> {
  if (_tauriAvailable !== null) {
    return _tauriAvailable;
  }

  // First check if window.__TAURI_INTERNALS__ exists
  if (typeof window === 'undefined' || !('__TAURI_INTERNALS__' in window)) {
    log.debug('probeTauriAvailability: __TAURI_INTERNALS__ not found');
    _tauriAvailable = false;
    return false;
  }

  // Try to actually invoke a simple command to verify Tauri is working
  try {
    // Use kernel_status as a lightweight health check
    await invoke('kernel_status');
    log.debug('probeTauriAvailability: kernel_status succeeded');
    _tauriAvailable = true;
    return true;
  } catch {
    // Try without plugin prefix - some Tauri versions don't use it
    try {
      // Just checking if invoke function exists is enough
      log.debug('probeTauriAvailability: Tauri invoke available');
      _tauriAvailable = true;
      return true;
    } catch {
      log.debug('probeTauriAvailability: Tauri invoke failed');
      _tauriAvailable = false;
      return false;
    }
  }
}

/**
 * ZCLAW Kernel Client
 *
 * Provides a GatewayClient-compatible interface that uses Tauri commands
 * to communicate with the internal ZCLAW Kernel instead of external WebSocket.
 */
export class KernelClient {
  private state: ConnectionState = 'disconnected';
  private eventListeners = new Map<string, Set<EventCallback>>();
  private kernelStatus: KernelStatus | null = null;
  private defaultAgentId: string = '';
  private config: KernelConfig = {};

  // State change callbacks
  onStateChange?: (state: ConnectionState) => void;
  onLog?: (level: string, message: string) => void;

  constructor(opts?: {
    url?: string;
    token?: string;
    autoReconnect?: boolean;
    reconnectInterval?: number;
    requestTimeout?: number;
    kernelConfig?: KernelConfig;
  }) {
    // Store kernel config if provided
    if (opts?.kernelConfig) {
      this.config = opts.kernelConfig;
    }
  }

  updateOptions(opts?: {
    url?: string;
    token?: string;
    autoReconnect?: boolean;
    reconnectInterval?: number;
    requestTimeout?: number;
    kernelConfig?: KernelConfig;
  }): void {
    if (opts?.kernelConfig) {
      this.config = opts.kernelConfig;
    }
  }

  /**
   * Set kernel configuration (must be called before connect)
   */
  setConfig(config: KernelConfig): void {
    this.config = config;
  }

  getState(): ConnectionState {
    return this.state;
  }

  /**
   * Initialize and connect to the internal Kernel
   */
  async connect(): Promise<void> {
    // Always try to (re)initialize - backend will handle config changes
    // by rebooting the kernel if needed
    this.setState('connecting');

    try {
      // Validate that we have required config
      if (!this.config.provider || !this.config.model || !this.config.apiKey) {
        throw new Error('请先在"模型与 API"设置页面配置模型');
      }

      // Initialize the kernel via Tauri command with config
      const configRequest = {
        provider: this.config.provider,
        model: this.config.model,
        apiKey: this.config.apiKey,
        baseUrl: this.config.baseUrl || null,
        apiProtocol: this.config.apiProtocol || 'openai',
      };

      log.debug('Initializing with config:', {
        provider: configRequest.provider,
        model: configRequest.model,
        hasApiKey: !!configRequest.apiKey,
        baseUrl: configRequest.baseUrl,
        apiProtocol: configRequest.apiProtocol,
      });

      const status = await invoke<KernelStatus>('kernel_init', {
        configRequest,
      });
      this.kernelStatus = status;

      // Get or create default agent using the configured model
      const agents = await this.listAgents();
      if (agents.length > 0) {
        this.defaultAgentId = agents[0].id;
      } else {
        // Create a default agent with the user's configured model
        // For Coding Plan providers, add a coding-focused system prompt
        const isCodingPlan = this.config.provider?.includes('coding') ||
          this.config.baseUrl?.includes('coding.dashscope');

        const systemPrompt = isCodingPlan
          ? '你是一个专业的编程助手。你可以帮助用户解决编程问题、写代码、调试、解释技术概念等。请用中文回答问题。'
          : '你是 ZCLAW 智能助手，可以帮助用户解决各种问题。请用中文回答。';

        const agent = await this.createAgent({
          name: 'Default Agent',
          description: 'ZCLAW default assistant',
          systemPrompt,
          provider: this.config.provider,
          model: this.config.model,
        });
        this.defaultAgentId = agent.id;
      }

      this.setState('connected');
      this.emitEvent('connected', { version: '0.1.0-internal' });
      this.log('info', 'Connected to internal ZCLAW Kernel');
    } catch (err: unknown) {
      const errorMessage = err instanceof Error ? err.message : String(err);
      this.setState('disconnected');
      this.log('error', `Failed to initialize kernel: ${errorMessage}`);
      throw new Error(`Failed to initialize kernel: ${errorMessage}`);
    }
  }

  /**
   * Connect using REST API (compatibility with GatewayClient)
   */
  async connectRest(): Promise<void> {
    return this.connect();
  }

  /**
   * Disconnect from kernel (no-op for internal kernel)
   */
  disconnect(): void {
    this.setState('disconnected');
    this.kernelStatus = null;
    this.log('info', 'Disconnected from internal kernel');
  }

  // === Agent Management ===

  /**
   * List all agents
   */
  async listAgents(): Promise<AgentInfo[]> {
    return invoke<AgentInfo[]>('agent_list');
  }

  /**
   * Get agent by ID
   */
  async getAgent(agentId: string): Promise<AgentInfo | null> {
    return invoke<AgentInfo | null>('agent_get', { agentId });
  }

  /**
   * Create a new agent
   */
  async createAgent(request: CreateAgentRequest): Promise<CreateAgentResponse> {
    return invoke<CreateAgentResponse>('agent_create', {
      request: {
        name: request.name,
        description: request.description,
        systemPrompt: request.systemPrompt,
        provider: request.provider || 'anthropic',
        model: request.model || 'claude-sonnet-4-20250514',
        maxTokens: request.maxTokens || 4096,
        temperature: request.temperature || 0.7,
      },
    });
  }

  /**
   * Delete an agent
   */
  async deleteAgent(agentId: string): Promise<void> {
    return invoke('agent_delete', { agentId });
  }

  // === Clone/Agent Adaptation (GatewayClient interface compatibility) ===

  /**
   * List clones — maps to listAgents() with field adaptation
   */
  async listClones(): Promise<{ clones: any[] }> {
    const agents = await this.listAgents();
    const clones = agents.map((agent) => ({
      id: agent.id,
      name: agent.name,
      role: agent.description,
      model: agent.model,
      createdAt: new Date().toISOString(),
    }));
    return { clones };
  }

  /**
   * Create clone — maps to createAgent()
   */
  async createClone(opts: {
    name: string;
    role?: string;
    model?: string;
    personality?: string;
    communicationStyle?: string;
    [key: string]: unknown;
  }): Promise<{ clone: any }> {
    const response = await this.createAgent({
      name: opts.name,
      description: opts.role,
      model: opts.model,
    });
    const clone = {
      id: response.id,
      name: response.name,
      role: opts.role,
      model: opts.model,
      personality: opts.personality,
      communicationStyle: opts.communicationStyle,
      createdAt: new Date().toISOString(),
    };
    return { clone };
  }

  /**
   * Delete clone — maps to deleteAgent()
   */
  async deleteClone(id: string): Promise<void> {
    return this.deleteAgent(id);
  }

  /**
   * Update clone — maps to kernel agent_update
   */
  async updateClone(id: string, updates: Record<string, unknown>): Promise<{ clone: unknown }> {
    await invoke('agent_update', {
      agentId: id,
      updates: {
        name: updates.name as string | undefined,
        description: updates.description as string | undefined,
        systemPrompt: updates.systemPrompt as string | undefined,
        model: updates.model as string | undefined,
        provider: updates.provider as string | undefined,
        maxTokens: updates.maxTokens as number | undefined,
        temperature: updates.temperature as number | undefined,
      },
    });

    // Return updated clone representation
    const clone = {
      id,
      name: updates.name,
      role: updates.description || updates.role,
      model: updates.model,
      personality: updates.personality,
      communicationStyle: updates.communicationStyle,
      systemPrompt: updates.systemPrompt,
    };
    return { clone };
  }

  // === Chat ===

  /**
   * Send a message and get a response
   */
  async chat(
    message: string,
    opts?: {
      sessionKey?: string;
      agentId?: string;
    }
  ): Promise<{ runId: string; sessionId?: string; response?: string }> {
    const agentId = opts?.agentId || this.defaultAgentId;

    if (!agentId) {
      throw new Error('No agent available');
    }

    const response = await invoke<ChatResponse>('agent_chat', {
      request: {
        agentId,
        message,
      },
    });

    return {
      runId: `run_${Date.now()}`,
      sessionId: opts?.sessionKey,
      response: response.content,
    };
  }

  /**
   * Send a message with streaming response via Tauri events
   */
  async chatStream(
    message: string,
    callbacks: StreamCallbacks,
    opts?: {
      sessionKey?: string;
      agentId?: string;
    }
  ): Promise<{ runId: string }> {
    const runId = crypto.randomUUID();
    const sessionId = opts?.sessionKey || runId;
    const agentId = opts?.agentId || this.defaultAgentId;

    if (!agentId) {
      callbacks.onError('No agent available');
      return { runId };
    }

    let unlisten: UnlistenFn | null = null;

    try {
      // Set up event listener for stream chunks
      unlisten = await listen<StreamChunkPayload>('stream:chunk', (event) => {
        const payload = event.payload;

        // Only process events for this session
        if (payload.sessionId !== sessionId) {
          return;
        }

        const streamEvent = payload.event;

        switch (streamEvent.type) {
          case 'delta':
            callbacks.onDelta(streamEvent.delta);
            break;

          case 'tool_start':
            log.debug('Tool started:', streamEvent.name, streamEvent.input);
            if (callbacks.onTool) {
              callbacks.onTool(
                streamEvent.name,
                JSON.stringify(streamEvent.input),
                ''
              );
            }
            break;

          case 'tool_end':
            log.debug('Tool ended:', streamEvent.name, streamEvent.output);
            if (callbacks.onTool) {
              callbacks.onTool(
                streamEvent.name,
                '',
                JSON.stringify(streamEvent.output)
              );
            }
            break;

          case 'handStart':
            log.debug('Hand started:', streamEvent.name, streamEvent.params);
            if (callbacks.onHand) {
              callbacks.onHand(streamEvent.name, 'running', undefined);
            }
            break;

          case 'handEnd':
            log.debug('Hand ended:', streamEvent.name, streamEvent.result);
            if (callbacks.onHand) {
              callbacks.onHand(streamEvent.name, 'completed', streamEvent.result);
            }
            break;

          case 'iteration_start':
            log.debug('Iteration started:', streamEvent.iteration, '/', streamEvent.maxIterations);
            // Don't need to notify user about iterations
            break;

          case 'complete':
            log.debug('Stream complete:', streamEvent.inputTokens, streamEvent.outputTokens);
            callbacks.onComplete(streamEvent.inputTokens, streamEvent.outputTokens);
            // Clean up listener
            if (unlisten) {
              unlisten();
              unlisten = null;
            }
            break;

          case 'error':
            log.error('Stream error:', streamEvent.message);
            callbacks.onError(streamEvent.message);
            // Clean up listener
            if (unlisten) {
              unlisten();
              unlisten = null;
            }
            break;
        }
      });

      // Invoke the streaming command
      await invoke('agent_chat_stream', {
        request: {
          agentId,
          sessionId,
          message,
        },
      });
    } catch (err: unknown) {
      const errorMessage = err instanceof Error ? err.message : String(err);
      callbacks.onError(errorMessage);

      // Clean up listener on error
      if (unlisten) {
        unlisten();
      }
    }

    return { runId };
  }

  /**
   * Cancel a stream (no-op for internal kernel)
   */
  cancelStream(_runId: string): void {
    // No-op: internal kernel doesn't support stream cancellation
  }

  // === Default Agent ===

  /**
   * Fetch default agent ID (returns current default)
   */
  async fetchDefaultAgentId(): Promise<string | null> {
    return this.defaultAgentId;
  }

  /**
   * Set default agent ID
   */
  setDefaultAgentId(agentId: string): void {
    this.defaultAgentId = agentId;
  }

  /**
   * Get default agent ID
   */
  getDefaultAgentId(): string {
    return this.defaultAgentId;
  }

  // === GatewayClient Compatibility ===

  /**
   * Health check
   */
  async health(): Promise<{ status: string; version?: string }> {
    if (this.kernelStatus?.initialized) {
      return { status: 'ok', version: '0.1.0-internal' };
    }
    return { status: 'not_initialized' };
  }

  /**
   * Get status
   */
  async status(): Promise<Record<string, unknown>> {
    const status = await invoke<KernelStatus>('kernel_status');
    return {
      initialized: status.initialized,
      agentCount: status.agentCount,
      defaultProvider: status.defaultProvider,
      defaultModel: status.defaultModel,
    };
  }

  // === Hands API ===

  /**
   * List all available hands
   */
  async listHands(): Promise<{
    hands: {
      id?: string;
      name: string;
      description?: string;
      status?: string;
      requirements_met?: boolean;
      category?: string;
      icon?: string;
      tool_count?: number;
      tools?: string[];
      metric_count?: number;
      metrics?: string[];
    }[]
  }> {
    const hands = await invoke<Array<{
      id?: string;
      name: string;
      description?: string;
      status?: string;
      requirements_met?: boolean;
      category?: string;
      icon?: string;
      tool_count?: number;
      tools?: string[];
      metric_count?: number;
      metrics?: string[];
    }>>('hand_list');
    return { hands: hands || [] };
  }

  /**
   * Get hand details
   */
  async getHand(name: string): Promise<{
    id?: string;
    name?: string;
    description?: string;
    status?: string;
    requirements_met?: boolean;
    category?: string;
    icon?: string;
    provider?: string;
    model?: string;
    requirements?: { description?: string; name?: string; met?: boolean; satisfied?: boolean; details?: string; hint?: string }[];
    tools?: string[];
    metrics?: string[];
    config?: Record<string, unknown>;
    tool_count?: number;
    metric_count?: number;
  }> {
    try {
      return await invoke('hand_get', { name });
    } catch {
      // Hand not found or kernel not initialized
      return {};
    }
  }

  /**
   * Trigger/execute a hand
   */
  async triggerHand(name: string, params?: Record<string, unknown>, autonomyLevel?: string): Promise<{ runId: string; status: string }> {
    const result = await invoke<{ instance_id: string; status: string }>('hand_execute', {
      id: name,
      input: params || {},
      ...(autonomyLevel ? { autonomyLevel } : {}),
    });
    return { runId: result.instance_id, status: result.status };
  }

  /**
   * Get hand run status
   */
  async getHandStatus(name: string, runId: string): Promise<{ status: string; result?: unknown }> {
    try {
      return await invoke('hand_run_status', { handName: name, runId });
    } catch {
      return { status: 'unknown' };
    }
  }

  /**
   * Approve a hand execution
   */
  async approveHand(name: string, runId: string, approved: boolean, reason?: string): Promise<{ status: string }> {
    return await invoke('hand_approve', { handName: name, runId, approved, reason });
  }

  /**
   * Cancel a hand execution
   */
  async cancelHand(name: string, runId: string): Promise<{ status: string }> {
    return await invoke('hand_cancel', { handName: name, runId });
  }

  /**
   * List hand runs (execution history)
   */
  async listHandRuns(name: string, opts?: { limit?: number; offset?: number }): Promise<{
    runs: {
      runId?: string;
      run_id?: string;
      id?: string;
      status?: string;
      startedAt?: string;
      started_at?: string;
      completedAt?: string;
      completed_at?: string;
      result?: unknown;
      error?: string;
    }[]
  }> {
    // Hand run history
    try {
      return await invoke('hand_run_list', { handName: name, ...opts });
    } catch {
      return { runs: [] };
    }
  }

  // === Skills API ===

  /**
   * List all discovered skills
   */
  async listSkills(): Promise<{
    skills: {
      id: string;
      name: string;
      description: string;
      version: string;
      capabilities: string[];
      tags: string[];
      mode: string;
      enabled: boolean;
      triggers: string[];
      category?: string;
    }[]
  }> {
    const skills = await invoke<Array<{
      id: string;
      name: string;
      description: string;
      version: string;
      capabilities: string[];
      tags: string[];
      mode: string;
      enabled: boolean;
      triggers: string[];
      category?: string;
    }>>('skill_list');
    return { skills: skills || [] };
  }

  /**
   * Refresh skills from directory
   */
  async refreshSkills(skillDir?: string): Promise<{
    skills: {
      id: string;
      name: string;
      description: string;
      version: string;
      capabilities: string[];
      tags: string[];
      mode: string;
      enabled: boolean;
      triggers: string[];
      category?: string;
    }[]
  }> {
    const skills = await invoke<Array<{
      id: string;
      name: string;
      description: string;
      version: string;
      capabilities: string[];
      tags: string[];
      mode: string;
      enabled: boolean;
      triggers: string[];
      category?: string;
    }>>('skill_refresh', { skillDir: skillDir || null });
    return { skills: skills || [] };
  }

  /**
   * Create a new skill
   */
  async createSkill(skill: {
    name: string;
    description?: string;
    triggers: Array<{ type: string; pattern?: string }>;
    actions: Array<{ type: string; params?: Record<string, unknown> }>;
    enabled?: boolean;
  }): Promise<{ skill?: {
    id: string;
    name: string;
    description: string;
    version: string;
    capabilities: string[];
    tags: string[];
    mode: string;
    enabled: boolean;
    triggers: string[];
    category?: string;
  } }> {
    const result = await invoke<{
      id: string;
      name: string;
      description: string;
      version: string;
      capabilities: string[];
      tags: string[];
      mode: string;
      enabled: boolean;
      triggers: string[];
      category?: string;
    }>('skill_create', {
      request: {
        name: skill.name,
        description: skill.description,
        triggers: skill.triggers.map(t => t.pattern || t.type),
        actions: skill.actions.map(a => a.type),
        enabled: skill.enabled,
      },
    });
    return { skill: result };
  }

  /**
   * Update an existing skill
   */
  async updateSkill(id: string, updates: {
    name?: string;
    description?: string;
    triggers?: Array<{ type: string; pattern?: string }>;
    actions?: Array<{ type: string; params?: Record<string, unknown> }>;
    enabled?: boolean;
  }): Promise<{ skill?: {
    id: string;
    name: string;
    description: string;
    version: string;
    capabilities: string[];
    tags: string[];
    mode: string;
    enabled: boolean;
    triggers: string[];
    category?: string;
  } }> {
    const result = await invoke<{
      id: string;
      name: string;
      description: string;
      version: string;
      capabilities: string[];
      tags: string[];
      mode: string;
      enabled: boolean;
      triggers: string[];
      category?: string;
    }>('skill_update', {
      id,
      request: {
        name: updates.name,
        description: updates.description,
        triggers: updates.triggers?.map(t => t.pattern || t.type),
        actions: updates.actions?.map(a => a.type),
        enabled: updates.enabled,
      },
    });
    return { skill: result };
  }

  /**
   * Delete a skill
   */
  async deleteSkill(id: string): Promise<void> {
    await invoke('skill_delete', { id });
  }

  /**
  async executeSkill(id: string, input?: Record<string, unknown>): Promise<{
    success: boolean;
    output?: unknown;
    error?: string;
    durationMs?: number;
  }> {
    // Autonomy check before executing skill
    const { canAutoExecute, getAutonomyManager } = await import('./autonomy-manager');
    const { canProceed, decision } = canAutoExecute('skill_install', 5);
    if (!canProceed) {
      return {
        success: false,
        error: `自主授权拒绝: ${decision.reason}`,
      };
    }

    const autonomyLevel = getAutonomyManager().getConfig().level;

    return invoke('skill_execute', {
      id,
      context: {},
      input: input || {},
      autonomyLevel,
    });
  }

  // === Triggers API ===

  /**
   * List all triggers
   * Returns empty array on error for graceful degradation
   */
  async listTriggers(): Promise<{
    triggers?: Array<{
      id: string;
      name: string;
      handId: string;
      triggerType: string;
      enabled: boolean;
      createdAt: string;
      modifiedAt: string;
      description?: string;
      tags: string[];
    }>
  }> {
    try {
      const triggers = await invoke<Array<{
        id: string;
        name: string;
        handId: string;
        triggerType: string;
        enabled: boolean;
        createdAt: string;
        modifiedAt: string;
        description?: string;
        tags: string[];
      }>>('trigger_list');
      return { triggers };
    } catch (error) {
      this.log('error', `[TriggersAPI] listTriggers failed: ${this.formatError(error)}`);
      return { triggers: [] };
    }
  }

  /**
   * Get a single trigger by ID
   * Returns null on error for graceful degradation
   */
  async getTrigger(id: string): Promise<{
    id: string;
    name: string;
    handId: string;
    triggerType: string;
    enabled: boolean;
    createdAt: string;
    modifiedAt: string;
    description?: string;
    tags: string[];
  } | null> {
    try {
      return await invoke<{
        id: string;
        name: string;
        handId: string;
        triggerType: string;
        enabled: boolean;
        createdAt: string;
        modifiedAt: string;
        description?: string;
        tags: string[];
      } | null>('trigger_get', { id });
    } catch (error) {
      this.log('error', `[TriggersAPI] getTrigger(${id}) failed: ${this.formatError(error)}`);
      return null;
    }
  }

  /**
   * Create a new trigger
   * Returns null on error for graceful degradation
   */
  async createTrigger(trigger: {
    id: string;
    name: string;
    handId: string;
    triggerType: { type: string; cron?: string; pattern?: string; path?: string; secret?: string; events?: string[] };
    enabled?: boolean;
    description?: string;
    tags?: string[];
  }): Promise<{
    id: string;
    name: string;
    handId: string;
    triggerType: string;
    enabled: boolean;
    createdAt: string;
    modifiedAt: string;
    description?: string;
    tags: string[];
  } | null> {
    try {
      return await invoke<{
        id: string;
        name: string;
        handId: string;
        triggerType: string;
        enabled: boolean;
        createdAt: string;
        modifiedAt: string;
        description?: string;
        tags: string[];
      }>('trigger_create', { request: trigger });
    } catch (error) {
      this.log('error', `[TriggersAPI] createTrigger(${trigger.id}) failed: ${this.formatError(error)}`);
      return null;
    }
  }

  /**
   * Update an existing trigger
   * Throws on error as this is a mutation operation that callers need to handle
   */
  async updateTrigger(id: string, updates: {
    name?: string;
    enabled?: boolean;
    handId?: string;
    triggerType?: { type: string; cron?: string; pattern?: string; path?: string; secret?: string; events?: string[] };
  }): Promise<{
    id: string;
    name: string;
    handId: string;
    triggerType: string;
    enabled: boolean;
    createdAt: string;
    modifiedAt: string;
    description?: string;
    tags: string[];
  }> {
    try {
      return await invoke<{
        id: string;
        name: string;
        handId: string;
        triggerType: string;
        enabled: boolean;
        createdAt: string;
        modifiedAt: string;
        description?: string;
        tags: string[];
      }>('trigger_update', { id, updates });
    } catch (error) {
      this.log('error', `[TriggersAPI] updateTrigger(${id}) failed: ${this.formatError(error)}`);
      throw error;
    }
  }

  /**
   * Delete a trigger
   * Throws on error as this is a destructive operation that callers need to handle
   */
  async deleteTrigger(id: string): Promise<void> {
    try {
      await invoke('trigger_delete', { id });
    } catch (error) {
      this.log('error', `[TriggersAPI] deleteTrigger(${id}) failed: ${this.formatError(error)}`);
      throw error;
    }
  }

  /**
   * Execute a trigger
   * Throws on error as callers need to know if execution failed
   */
  async executeTrigger(id: string, input?: Record<string, unknown>): Promise<Record<string, unknown>> {
    try {
      return await invoke<Record<string, unknown>>('trigger_execute', { id, input: input || {} });
    } catch (error) {
      this.log('error', `[TriggersAPI] executeTrigger(${id}) failed: ${this.formatError(error)}`);
      throw error;
    }
  }

  // === Approvals API ===

  async listApprovals(_status?: string): Promise<{
    approvals: Array<{
      id: string;
      handId: string;
      status: string;
      createdAt: string;
      input: Record<string, unknown>;
    }>
  }> {
    try {
      const approvals = await invoke<Array<{
        id: string;
        handId: string;
        status: string;
        createdAt: string;
        input: Record<string, unknown>;
      }>>('approval_list');
      return { approvals };
    } catch (error) {
      log.error('listApprovals error:', error);
      return { approvals: [] };
    }
  }

  async respondToApproval(approvalId: string, approved: boolean, reason?: string): Promise<void> {
    return invoke('approval_respond', { id: approvalId, approved, reason });
  }

  /**
   * REST API compatibility methods
   */
  public getRestBaseUrl(): string {
    return ''; // Internal kernel doesn't use REST
  }

  public async restGet<T>(_path: string): Promise<T> {
    throw new Error('REST API not available for internal kernel');
  }

  public async restPost<T>(_path: string, _body?: unknown): Promise<T> {
    throw new Error('REST API not available for internal kernel');
  }

  public async restPut<T>(_path: string, _body?: unknown): Promise<T> {
    throw new Error('REST API not available for internal kernel');
  }

  public async restDelete<T>(_path: string): Promise<T> {
    throw new Error('REST API not available for internal kernel');
  }

  public async restPatch<T>(_path: string, _body?: unknown): Promise<T> {
    throw new Error('REST API not available for internal kernel');
  }

  // === Events ===

  /**
   * Subscribe to events
   */
  on(event: string, callback: EventCallback): () => void {
    if (!this.eventListeners.has(event)) {
      this.eventListeners.set(event, new Set());
    }
    this.eventListeners.get(event)!.add(callback);

    return () => {
      this.eventListeners.get(event)?.delete(callback);
    };
  }

  /**
   * Subscribe to agent stream events (GatewayClient compatibility)
   * Note: KernelClient handles streaming via chatStream callbacks directly,
   * so this is a no-op that returns an empty unsubscribe function.
   */
  onAgentStream(_callback: (delta: { stream: 'assistant' | 'tool' | 'lifecycle' | 'hand' | 'workflow'; delta?: string; content?: string; runId?: string }) => void): () => void {
    // KernelClient uses chatStream callbacks for streaming, not a separate event stream
    // Return empty unsubscribe for compatibility
    return () => {};
  }

  // === A2A (Agent-to-Agent) API ===

  /**
   * Send a direct A2A message from one agent to another
   */
  /**
   * Send a direct A2A message from one agent to another
   */
  async a2aSend(from: string, to: string, payload: unknown, messageType?: string): Promise<void> {
    await invoke('agent_a2a_send', {
      from,
      to,
      payload,
      messageType: messageType || 'notification',
    });
  }

  /**
   * Broadcast a message from an agent to all other agents
   */
  async a2aBroadcast(from: string, payload: unknown): Promise<void> {
    await invoke('agent_a2a_broadcast', { from, payload });
  }

  /**
   * Discover agents that have a specific capability
   */
  async a2aDiscover(capability: string): Promise<Array<{
    id: string;
    name: string;
    description: string;
    capabilities: Array<{ name: string; description: string }>;
    role: string;
    priority: number;
  }>> {
    return await invoke('agent_a2a_discover', { capability });
  }

  /**
   * Delegate a task to another agent and wait for response
   */
  async a2aDelegateTask(from: string, to: string, task: string, timeoutMs?: number): Promise<unknown> {
    return await invoke('agent_a2a_delegate_task', {
      from,
      to,
      task,
      timeoutMs: timeoutMs || 30000,
    });
  }

  // === Internal ===

  private setState(state: ConnectionState): void {
    this.state = state;
    this.onStateChange?.(state);
    this.emitEvent('state', state);
  }

  private emitEvent(event: string, payload: unknown): void {
    const listeners = this.eventListeners.get(event);
    if (listeners) {
      for (const cb of listeners) {
        try {
          cb(payload);
        } catch {
          /* ignore listener errors */
        }
      }
    }
  }

  private log(level: string, message: string): void {
    this.onLog?.(level, message);
  }

  /**
   * Format error for consistent logging
   */
  private formatError(error: unknown): string {
    if (error instanceof Error) {
      return error.message;
    }
    return String(error);
  }
}

// === Singleton ===

let _client: KernelClient | null = null;

/**
 * Get the kernel client singleton
 */
export function getKernelClient(opts?: ConstructorParameters<typeof KernelClient>[0]): KernelClient {
  if (!_client) {
    _client = new KernelClient(opts);
  } else if (opts) {
    _client.updateOptions(opts);
  }
  return _client;
}

/**
 * Check if internal kernel mode is available
 */
export function isInternalKernelAvailable(): boolean {
  return isTauriRuntime();
}