/**
 * HarborForge Plugin for OpenClaw
 *
 * Provides monitor-related tools and exposes OpenClaw metadata
 * for the HarborForge Monitor bridge (via monitor_port).
 *
 * Also integrates with HarborForge Calendar system to wake agents
 * for scheduled tasks (PLG-CAL-002, PLG-CAL-004).
 *
 * Sidecar architecture has been removed. Telemetry data is now
 * served directly by the plugin when Monitor queries via the
 * local monitor_port communication path.
 */
import { hostname, freemem, totalmem, uptime, loadavg, platform } from 'os';
import { getPluginConfig } from './core/config';
import { MonitorBridgeClient, type OpenClawMeta } from './core/monitor-bridge';
import { registerGatewayStartHook } from './hooks/gateway-start';
import { registerGatewayStopHook } from './hooks/gateway-stop';
import {
  createCalendarBridgeClient,
  createCalendarScheduler,
  CalendarScheduler,
  AgentWakeContext,
} from './calendar';

interface PluginAPI {
  logger: {
    info: (...args: any[]) => void;
    error: (...args: any[]) => void;
    debug: (...args: any[]) => void;
    warn: (...args: any[]) => void;
  };
  version?: string;
  config?: Record<string, unknown>;
  pluginConfig?: Record<string, unknown>;
  on: (event: string, handler: () => void) => void;
  registerTool: (factory: (ctx: any) => any) => void;
  /** Spawn a sub-agent with task context (OpenClaw 2.1+) */
  spawn?: (options: {
    agentId?: string;
    task: string;
    model?: string;
    timeoutSeconds?: number;
  }) => Promise<{ sessionId: string; status: string }>;
  /** Get current agent status */
  getAgentStatus?: () => Promise<{ status: string } | null>;
}

export default {
  id: 'harbor-forge',
  name: 'HarborForge',
  register(api: PluginAPI) {
    const logger = api.logger || {
      info: (...args: any[]) => console.log('[HarborForge]', ...args),
      error: (...args: any[]) => console.error('[HarborForge]', ...args),
      debug: (...args: any[]) => console.debug('[HarborForge]', ...args),
      warn: (...args: any[]) => console.warn('[HarborForge]', ...args),
    };

    function resolveConfig() {
      return getPluginConfig(api);
    }

    /**
     * Get the monitor bridge client if monitor_port is configured.
     * Legacy alias monitorPort is still accepted.
     */
    function getBridgeClient(): MonitorBridgeClient | null {
      const live = resolveConfig() as any;
      const port = live.monitor_port ?? live.monitorPort;
      if (!port || port <= 0) return null;
      return new MonitorBridgeClient(port);
    }

    /**
     * Collect current system telemetry snapshot.
     * This data is exposed to the Monitor bridge when it queries the plugin.
     */
    function collectTelemetry() {
      const live = resolveConfig();
      const load = loadavg();
      return {
        identifier: live.identifier || hostname(),
        platform: platform(),
        hostname: hostname(),
        uptime: uptime(),
        memory: {
          total: totalmem(),
          free: freemem(),
          used: totalmem() - freemem(),
          usagePercent: ((totalmem() - freemem()) / totalmem()) * 100,
        },
        load: {
          avg1: load[0],
          avg5: load[1],
          avg15: load[2],
        },
        openclaw: {
          version: api.version || 'unknown',
          pluginVersion: '0.3.1', // Bumped for PLG-CAL-004
        },
        timestamp: new Date().toISOString(),
      };
    }

    // Periodic metadata push interval handle
    let metaPushInterval: ReturnType<typeof setInterval> | null = null;

    // Calendar scheduler instance
    let calendarScheduler: CalendarScheduler | null = null;

    /**
     * Push OpenClaw metadata to the Monitor bridge.
     * This enriches Monitor heartbeats with OpenClaw version/plugin/agent info.
     * Failures are non-fatal — Monitor continues to work without this data.
     */
    async function pushMetaToMonitor() {
      const bridgeClient = getBridgeClient();
      if (!bridgeClient) return;

      const meta: OpenClawMeta = {
        version: api.version || 'unknown',
        plugin_version: '0.3.1',
        agents: [], // TODO: populate from api agent list when available
      };

      const ok = await bridgeClient.pushOpenClawMeta(meta);
      if (ok) {
        logger.debug('pushed OpenClaw metadata to Monitor bridge');
      } else {
        logger.debug('Monitor bridge unreachable for metadata push (non-fatal)');
      }
    }

    /**
     * Get current agent status from OpenClaw.
     * Falls back to querying backend if OpenClaw API unavailable.
     */
    async function getAgentStatus(): Promise<'idle' | 'on_call' | 'busy' | 'exhausted' | 'offline' | null> {
      // Try OpenClaw API first (if available)
      if (api.getAgentStatus) {
        try {
          const status = await api.getAgentStatus();
          if (status?.status) {
            return status.status as 'idle' | 'on_call' | 'busy' | 'exhausted' | 'offline';
          }
        } catch (err) {
          logger.debug('Failed to get agent status from OpenClaw API:', err);
        }
      }

      // Fallback: query backend for agent status
      const live = resolveConfig();
      const agentId = process.env.AGENT_ID || 'unknown';
      try {
        const response = await fetch(`${live.backendUrl}/calendar/agent/status?agent_id=${agentId}`, {
          headers: {
            'X-Agent-ID': agentId,
            'X-Claw-Identifier': live.identifier || hostname(),
          },
        });
        if (response.ok) {
          const data = await response.json();
          return data.status;
        }
      } catch (err) {
        logger.debug('Failed to get agent status from backend:', err);
      }

      return null;
    }

    /**
     * Wake/spawn agent with task context for slot execution.
     * This is the callback invoked by CalendarScheduler when a slot is ready.
     */
    async function wakeAgent(context: AgentWakeContext): Promise<boolean> {
      logger.info(`Waking agent for slot: ${context.taskDescription}`);

      try {
        // Method 1: Use OpenClaw spawn API if available (preferred)
        if (api.spawn) {
          const result = await api.spawn({
            task: context.prompt,
            timeoutSeconds: context.slot.estimated_duration * 60, // Convert to seconds
          });

          if (result?.sessionId) {
            logger.info(`Agent spawned for calendar slot: session=${result.sessionId}`);

            // Track session completion
            trackSessionCompletion(result.sessionId, context);
            return true;
          }
        }

        // Method 2: Send notification/alert to wake agent (fallback)
        // This relies on the agent's heartbeat to check for notifications
        logger.warn('OpenClaw spawn API not available, using notification fallback');

        // Send calendar wakeup notification via backend
        const live = resolveConfig();
        const agentId = process.env.AGENT_ID || 'unknown';

        const notifyResponse = await fetch(`${live.backendUrl}/calendar/agent/notify`, {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json',
            'X-Agent-ID': agentId,
            'X-Claw-Identifier': live.identifier || hostname(),
          },
          body: JSON.stringify({
            agent_id: agentId,
            message: context.prompt,
            slot_id: context.slot.id || context.slot.virtual_id,
            task_description: context.taskDescription,
          }),
        });

        return notifyResponse.ok;

      } catch (err) {
        logger.error('Failed to wake agent:', err);
        return false;
      }
    }

    /**
     * Track session completion and update slot status accordingly.
     */
    function trackSessionCompletion(sessionId: string, context: AgentWakeContext): void {
      // Poll for session completion (simplified approach)
      // In production, this would use webhooks or event streaming
      const pollInterval = 30000; // 30 seconds
      const maxDuration = context.slot.estimated_duration * 60 * 1000; // Convert to ms
      const startTime = Date.now();

      const poll = async () => {
        if (!calendarScheduler) return;

        const elapsed = Date.now() - startTime;

        // Check if session is complete (would use actual API in production)
        // For now, estimate completion based on duration
        if (elapsed >= maxDuration) {
          // Assume completion
          const actualMinutes = Math.round(elapsed / 60000);
          await calendarScheduler.completeCurrentSlot(actualMinutes);
          return;
        }

        // Continue polling
        setTimeout(poll, pollInterval);
      };

      // Start polling
      setTimeout(poll, pollInterval);
    }

    /**
     * Initialize and start the calendar scheduler.
     */
    function startCalendarScheduler(): void {
      const live = resolveConfig();
      const agentId = process.env.AGENT_ID || 'unknown';

      // Create calendar bridge client
      const calendarBridge = createCalendarBridgeClient(
        api,
        live.backendUrl || 'https://monitor.hangman-lab.top',
        agentId
      );

      // Create and start scheduler
      calendarScheduler = createCalendarScheduler({
        bridge: calendarBridge,
        getAgentStatus,
        wakeAgent,
        logger,
        heartbeatIntervalMs: 60000, // 1 minute
        debug: live.logLevel === 'debug',
      });

      calendarScheduler.start();
      logger.info('Calendar scheduler started');
    }

    /**
     * Stop the calendar scheduler.
     */
    function stopCalendarScheduler(): void {
      if (calendarScheduler) {
        calendarScheduler.stop();
        calendarScheduler = null;
        logger.info('Calendar scheduler stopped');
      }
    }

    registerGatewayStartHook(api, {
      logger,
      pushMetaToMonitor,
      startCalendarScheduler,
      setMetaPushInterval(handle) {
        metaPushInterval = handle;
      },
    });

    registerGatewayStopHook(api, {
      logger,
      getMetaPushInterval() {
        return metaPushInterval;
      },
      clearMetaPushInterval() {
        metaPushInterval = null;
      },
      stopCalendarScheduler,
    });

    // Tool: plugin status
    api.registerTool(() => ({
      name: 'harborforge_status',
      description: 'Get HarborForge plugin status and current telemetry snapshot',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        const live = resolveConfig();
        const bridgeClient = getBridgeClient();
        let monitorBridge = null;

        if (bridgeClient) {
          const health = await bridgeClient.health();
          monitorBridge = health
            ? { connected: true, ...health }
            : { connected: false, error: 'Monitor bridge unreachable' };
        }

        // Get calendar scheduler status
        const calendarStatus = calendarScheduler ? {
          running: calendarScheduler.isRunning(),
          processing: calendarScheduler.isProcessing(),
          currentSlot: calendarScheduler.getCurrentSlot(),
          isRestartPending: calendarScheduler.isRestartPending(),
        } : null;

        return {
          enabled: live.enabled !== false,
          config: {
            backendUrl: live.backendUrl,
            identifier: live.identifier || hostname(),
            monitorPort: (live as any).monitor_port ?? (live as any).monitorPort ?? null,
            reportIntervalSec: live.reportIntervalSec,
            hasApiKey: Boolean(live.apiKey),
          },
          monitorBridge,
          calendar: calendarStatus,
          telemetry: collectTelemetry(),
        };
      },
    }));

    // Tool: telemetry snapshot (for Monitor bridge queries)
    api.registerTool(() => ({
      name: 'harborforge_telemetry',
      description: 'Get current system telemetry data for HarborForge Monitor',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        return collectTelemetry();
      },
    }));

    // Tool: query Monitor bridge for host hardware telemetry
    api.registerTool(() => ({
      name: 'harborforge_monitor_telemetry',
      description: 'Query HarborForge Monitor bridge for host hardware telemetry (CPU, memory, disk, etc.)',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        const bridgeClient = getBridgeClient();
        if (!bridgeClient) {
          return {
            error: 'Monitor bridge not configured (monitor_port not set or 0)',
          };
        }

        const data = await bridgeClient.telemetry();
        if (!data) {
          return {
            error: 'Monitor bridge unreachable',
          };
        }

        return data;
      },
    }));

    // Tool: calendar slot management
    api.registerTool(() => ({
      name: 'harborforge_calendar_status',
      description: 'Get current calendar scheduler status and pending slots',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        if (!calendarScheduler) {
          return { error: 'Calendar scheduler not running' };
        }

        return {
          running: calendarScheduler.isRunning(),
          processing: calendarScheduler.isProcessing(),
          currentSlot: calendarScheduler.getCurrentSlot(),
          state: calendarScheduler.getState(),
          isRestartPending: calendarScheduler.isRestartPending(),
          stateFilePath: calendarScheduler.getStateFilePath(),
        };
      },
    }));

    // Tool: complete current slot (for agent to report completion)
    api.registerTool(() => ({
      name: 'harborforge_calendar_complete',
      description: 'Complete the current calendar slot with actual duration',
      parameters: {
        type: 'object',
        properties: {
          actualDurationMinutes: {
            type: 'number',
            description: 'Actual time spent on the task in minutes',
          },
        },
        required: ['actualDurationMinutes'],
      },
      async execute(params: { actualDurationMinutes: number }) {
        if (!calendarScheduler) {
          return { error: 'Calendar scheduler not running' };
        }

        await calendarScheduler.completeCurrentSlot(params.actualDurationMinutes);
        return { success: true, message: 'Slot completed' };
      },
    }));

    // Tool: abort current slot (for agent to report failure)
    api.registerTool(() => ({
      name: 'harborforge_calendar_abort',
      description: 'Abort the current calendar slot',
      parameters: {
        type: 'object',
        properties: {
          reason: {
            type: 'string',
            description: 'Reason for aborting',
          },
        },
      },
      async execute(params: { reason?: string }) {
        if (!calendarScheduler) {
          return { error: 'Calendar scheduler not running' };
        }

        await calendarScheduler.abortCurrentSlot(params.reason);
        return { success: true, message: 'Slot aborted' };
      },
    }));

    // Tool: pause current slot
    api.registerTool(() => ({
      name: 'harborforge_calendar_pause',
      description: 'Pause the current calendar slot',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        if (!calendarScheduler) {
          return { error: 'Calendar scheduler not running' };
        }

        await calendarScheduler.pauseCurrentSlot();
        return { success: true, message: 'Slot paused' };
      },
    }));

    // Tool: resume current slot
    api.registerTool(() => ({
      name: 'harborforge_calendar_resume',
      description: 'Resume the paused calendar slot',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        if (!calendarScheduler) {
          return { error: 'Calendar scheduler not running' };
        }

        await calendarScheduler.resumeCurrentSlot();
        return { success: true, message: 'Slot resumed' };
      },
    }));

    // Tool: check ScheduledGatewayRestart status
    api.registerTool(() => ({
      name: 'harborforge_restart_status',
      description: 'Check if a gateway restart is pending (PLG-CAL-004)',
      parameters: {
        type: 'object',
        properties: {},
      },
      async execute() {
        if (!calendarScheduler) {
          return { error: 'Calendar scheduler not running' };
        }

        const isPending = calendarScheduler.isRestartPending();
        const stateFilePath = calendarScheduler.getStateFilePath();

        return {
          isRestartPending: isPending,
          stateFilePath: stateFilePath,
          message: isPending
            ? 'A gateway restart has been scheduled. The scheduler has been paused.'
            : 'No gateway restart is pending.',
        };
      },
    }));

    logger.info('HarborForge plugin registered (id: harbor-forge)');
  },
};