/**
 * Dashboard Data Hook
 *
 * Provides data for the main dashboard including:
 * - Quick stats (projects, agents, issues, approvals)
 * - Recent projects
 * - Pending approvals
 *
 * Uses mock data until backend endpoints are available.
 *
 * @see Issue #53
 */

import { useQuery } from '@tanstack/react-query';
import type { Project, ProjectStatus } from '@/components/projects/types';

// ============================================================================
// Types
// ============================================================================

export interface DashboardStats {
  activeProjects: number;
  runningAgents: number;
  openIssues: number;
  pendingApprovals: number;
}

export interface DashboardProject extends Project {
  progress: number;
  openIssues: number;
  activeAgents: number;
  currentSprint?: string;
  lastActivity: string;
}

export interface PendingApproval {
  id: string;
  type: 'sprint_boundary' | 'code_review' | 'architecture_decision' | 'deployment';
  title: string;
  description: string;
  projectId: string;
  projectName: string;
  requestedBy: string;
  requestedAt: string;
  priority: 'low' | 'medium' | 'high' | 'critical';
}

export interface DashboardData {
  stats: DashboardStats;
  recentProjects: DashboardProject[];
  pendingApprovals: PendingApproval[];
}

// ============================================================================
// Mock Data
// ============================================================================

const mockStats: DashboardStats = {
  activeProjects: 3,
  runningAgents: 8,
  openIssues: 24,
  pendingApprovals: 2,
};

const mockProjects: DashboardProject[] = [
  {
    id: 'proj-001',
    name: 'E-Commerce Platform Redesign',
    description: 'Complete redesign of the e-commerce platform with modern UI/UX',
    status: 'active' as ProjectStatus,
    autonomy_level: 'milestone',
    created_at: '2025-11-15T10:00:00Z',
    updated_at: '2025-12-30T14:30:00Z',
    owner_id: 'user-001',
    progress: 67,
    openIssues: 12,
    activeAgents: 4,
    currentSprint: 'Sprint 3',
    lastActivity: '2 minutes ago',
  },
  {
    id: 'proj-002',
    name: 'Mobile Banking App',
    description: 'Native mobile app for banking services with biometric authentication',
    status: 'active' as ProjectStatus,
    autonomy_level: 'autonomous',
    created_at: '2025-11-20T09:00:00Z',
    updated_at: '2025-12-30T12:00:00Z',
    owner_id: 'user-001',
    progress: 45,
    openIssues: 8,
    activeAgents: 5,
    currentSprint: 'Sprint 2',
    lastActivity: '15 minutes ago',
  },
  {
    id: 'proj-003',
    name: 'Internal HR Portal',
    description: 'Employee self-service portal for HR operations',
    status: 'paused' as ProjectStatus,
    autonomy_level: 'full_control',
    created_at: '2025-10-01T08:00:00Z',
    updated_at: '2025-12-28T16:00:00Z',
    owner_id: 'user-001',
    progress: 23,
    openIssues: 5,
    activeAgents: 0,
    currentSprint: 'Sprint 1',
    lastActivity: '2 days ago',
  },
  {
    id: 'proj-004',
    name: 'API Gateway Modernization',
    description: 'Migrate legacy API gateway to cloud-native architecture',
    status: 'active' as ProjectStatus,
    autonomy_level: 'milestone',
    created_at: '2025-12-01T11:00:00Z',
    updated_at: '2025-12-30T10:00:00Z',
    owner_id: 'user-001',
    progress: 82,
    openIssues: 3,
    activeAgents: 2,
    currentSprint: 'Sprint 4',
    lastActivity: '1 hour ago',
  },
  {
    id: 'proj-005',
    name: 'Customer Analytics Dashboard',
    description: 'Real-time analytics dashboard for customer behavior insights',
    status: 'completed' as ProjectStatus,
    autonomy_level: 'autonomous',
    created_at: '2025-09-01T10:00:00Z',
    updated_at: '2025-12-15T17:00:00Z',
    owner_id: 'user-001',
    progress: 100,
    openIssues: 0,
    activeAgents: 0,
    lastActivity: '2 weeks ago',
  },
  {
    id: 'proj-006',
    name: 'DevOps Pipeline Automation',
    description: 'Automate CI/CD pipelines with AI-assisted deployments',
    status: 'active' as ProjectStatus,
    autonomy_level: 'milestone',
    created_at: '2025-12-10T14:00:00Z',
    updated_at: '2025-12-30T09:00:00Z',
    owner_id: 'user-001',
    progress: 35,
    openIssues: 6,
    activeAgents: 3,
    currentSprint: 'Sprint 1',
    lastActivity: '30 minutes ago',
  },
];

const mockApprovals: PendingApproval[] = [
  {
    id: 'approval-001',
    type: 'sprint_boundary',
    title: 'Sprint 3 Completion Review',
    description: 'Review sprint deliverables and approve transition to Sprint 4',
    projectId: 'proj-001',
    projectName: 'E-Commerce Platform Redesign',
    requestedBy: 'Product Owner Agent',
    requestedAt: '2025-12-30T14:00:00Z',
    priority: 'high',
  },
  {
    id: 'approval-002',
    type: 'architecture_decision',
    title: 'Database Migration Strategy',
    description: 'Approve PostgreSQL to CockroachDB migration plan',
    projectId: 'proj-004',
    projectName: 'API Gateway Modernization',
    requestedBy: 'Architect Agent',
    requestedAt: '2025-12-30T10:30:00Z',
    priority: 'medium',
  },
];

// ============================================================================
// Hook
// ============================================================================

/**
 * Fetches dashboard data (stats, recent projects, pending approvals)
 *
 * @returns Query result with dashboard data
 */
export function useDashboard() {
  return useQuery<DashboardData>({
    queryKey: ['dashboard'],
    queryFn: async () => {
      // Simulate network delay
      await new Promise((resolve) => setTimeout(resolve, 500));

      // Return mock data
      // TODO: Replace with actual API call when backend is ready
      // const response = await apiClient.get('/api/v1/dashboard');
      // return response.data;

      return {
        stats: mockStats,
        recentProjects: mockProjects,
        pendingApprovals: mockApprovals,
      };
    },
    staleTime: 30000, // 30 seconds
    refetchInterval: 60000, // Refetch every minute
  });
}

/**
 * Fetches only dashboard stats
 */
export function useDashboardStats() {
  return useQuery<DashboardStats>({
    queryKey: ['dashboard', 'stats'],
    queryFn: async () => {
      await new Promise((resolve) => setTimeout(resolve, 300));
      return mockStats;
    },
    staleTime: 30000,
    refetchInterval: 60000,
  });
}

/**
 * Fetches recent projects for dashboard
 *
 * @param limit - Maximum number of projects to return
 */
export function useRecentProjects(limit: number = 6) {
  return useQuery<DashboardProject[]>({
    queryKey: ['dashboard', 'recentProjects', limit],
    queryFn: async () => {
      await new Promise((resolve) => setTimeout(resolve, 400));
      return mockProjects.slice(0, limit);
    },
    staleTime: 30000,
  });
}

/**
 * Fetches pending approvals
 */
export function usePendingApprovals() {
  return useQuery<PendingApproval[]>({
    queryKey: ['dashboard', 'pendingApprovals'],
    queryFn: async () => {
      await new Promise((resolve) => setTimeout(resolve, 300));
      return mockApprovals;
    },
    staleTime: 30000,
  });
}