/**
 * Real Data Hook - Fetches live data from WidgetTDC Backend
 * Replaces mock/simulated data with real API data
 */

import { useState, useEffect, useCallback } from 'react';
import { API_URL } from '../config/api';

// Types for real data
export interface LogEntry {
  id: string;
  timestamp: string;
  level: 'debug' | 'info' | 'warn' | 'error';
  source: string;
  message: string;
}

export interface GraphStats {
  nodes: number;
  relationships: number;
  timestamp: string;
}

export interface SystemHealth {
  status: string;
  registeredTools: number;
  services: {
    neo4j: { healthy: boolean };
    vectorStore: { healthy: boolean; backend: string };
  };
}

export interface HyperMetrics {
  totalThoughts: number;
  toolUsageRate: number;
  activeAgents: number;
}

export interface RealDataState {
  logs: LogEntry[];
  graphStats: GraphStats | null;
  health: SystemHealth | null;
  hyperMetrics: HyperMetrics | null;
  isLoading: boolean;
  error: string | null;
  lastUpdated: number;
}

export const useRealData = (refreshInterval = 5000) => {
  const [state, setState] = useState<RealDataState>({
    logs: [],
    graphStats: null,
    health: null,
    hyperMetrics: null,
    isLoading: true,
    error: null,
    lastUpdated: 0,
  });

  const fetchData = useCallback(async () => {
    try {
      const [logsRes, graphRes, healthRes, hyperRes] = await Promise.all([
        fetch(`${API_URL}/api/logs`).catch(() => null),
        fetch(`${API_URL}/api/evolution/graph/stats`).catch(() => null),
        fetch(`${API_URL}/health`).catch(() => null),
        fetch(`${API_URL}/api/hyper/status`).catch(() => null),
      ]);

      const logs = logsRes?.ok ? (await logsRes.json()).entries?.slice(0, 50) || [] : [];
      const graphStats = graphRes?.ok ? await graphRes.json() : null;
      const health = healthRes?.ok ? await healthRes.json() : null;
      const hyperData = hyperRes?.ok ? await hyperRes.json() : null;

      setState({
        logs,
        graphStats: graphStats
          ? {
              nodes: graphStats.stats?.nodes || 0,
              relationships: graphStats.stats?.relationships || 0,
              timestamp: graphStats.timestamp,
            }
          : null,
        health: health
          ? {
              status: health.status,
              registeredTools: health.registeredTools || 0,
              services: health.services || {},
            }
          : null,
        hyperMetrics: hyperData?.metrics || null,
        isLoading: false,
        error: null,
        lastUpdated: Date.now(),
      });
    } catch (err) {
      setState(prev => ({
        ...prev,
        isLoading: false,
        error: (err as Error).message,
      }));
    }
  }, []);

  useEffect(() => {
    fetchData();
    const interval = setInterval(fetchData, refreshInterval);
    return () => clearInterval(interval);
  }, [fetchData, refreshInterval]);

  // Derived metrics from real data
  const metrics = {
    totalNodes: state.graphStats?.nodes || 0,
    totalRelationships: state.graphStats?.relationships || 0,
    totalTools: state.health?.registeredTools || 0,
    activeAgents: state.hyperMetrics?.activeAgents || 0,
    systemStatus: state.health?.status || 'unknown',
    neo4jHealthy: state.health?.services?.neo4j?.healthy || false,
    vectorStoreHealthy: state.health?.services?.vectorStore?.healthy || false,
    recentErrors: state.logs.filter(l => l.level === 'error').length,
    recentWarnings: state.logs.filter(l => l.level === 'warn').length,
  };

  // Transform logs to events for widgets
  const events = state.logs.map(log => ({
    id: log.id,
    time: new Date(log.timestamp).toLocaleTimeString('da-DK'),
    message: log.message,
    level: log.level,
    source: log.source,
  }));

  return {
    ...state,
    metrics,
    events,
    refresh: fetchData,
  };
};

// Hook for real-time log streaming
export const useLogStream = (maxLogs = 20) => {
  const [logs, setLogs] = useState<LogEntry[]>([]);

  useEffect(() => {
    const fetchLogs = async () => {
      try {
        const res = await fetch(`${API_URL}/api/logs`);
        if (res.ok) {
          const data = await res.json();
          setLogs(data.entries?.slice(0, maxLogs) || []);
        }
      } catch {
        // Silent fail
      }
    };

    fetchLogs();
    const interval = setInterval(fetchLogs, 3000);
    return () => clearInterval(interval);
  }, [maxLogs]);

  return logs;
};

export default useRealData;