'use server';

import { db, policySettings, type PolicySetting } from '@/lib/db';
import { getUserAuth } from '@/lib/auth/utils';
import { eq, ilike, or, desc, and, ne, isNotNull } from 'drizzle-orm';
import { env } from '@/lib/env.mjs';
import { syncQueue } from '@/lib/queue/syncQueue';

export interface PolicySettingSearchResult {
  id: string;
  policyName: string;
  policyType: string;
  settingName: string;
  settingValue: string;
  lastSyncedAt: Date;
}

export interface SearchResult {
  success: boolean;
  data?: PolicySettingSearchResult[];
  error?: string;
  totalCount?: number;
}

export interface GetSettingResult {
  success: boolean;
  data?: PolicySetting;
  error?: string;
}

export interface RecentSettingsResult {
  success: boolean;
  data?: PolicySettingSearchResult[];
  error?: string;
}

export interface AllSettingsResult {
  success: boolean;
  data?: PolicySettingSearchResult[];
  error?: string;
  totalCount?: number;
}

/**
 * Search policy settings by keyword across settingName and settingValue
 * 
 * **Security**: This function enforces tenant isolation by:
 * 1. Validating user session via getUserAuth()
 * 2. Extracting tenantId from session
 * 3. Including explicit WHERE tenantId = ? in ALL queries
 * 
 * @param searchTerm - Search query (min 2 characters)
 * @param limit - Maximum number of results (default 100, max 200)
 * @returns Search results filtered by user's tenant
 */
export async function searchPolicySettings(
  searchTerm: string,
  limit: number = 100
): Promise<SearchResult> {
  try {
    const { session } = await getUserAuth();
    
    // T017: Explicit security check - must have authenticated session
    if (!session?.user) {
      return { success: false, error: 'Unauthorized' };
    }

    // T017: Explicit security check - must have tenantId in session
    const tenantId = session.user.tenantId;
    if (!tenantId) {
      return { success: false, error: 'Tenant not found' };
    }

    if (searchTerm.length < 2) {
      return { success: false, error: 'Search term too short (min 2 characters)' };
    }

    // Limit search term length to prevent abuse
    const sanitizedSearchTerm = searchTerm.slice(0, 200);
    const searchPattern = `%${sanitizedSearchTerm}%`;

    // Enforce maximum limit
    const safeLimit = Math.min(Math.max(1, limit), 200);

    // Explicit WHERE clause filters by tenantId FIRST for security + null filtering
    const results = await db
      .select({
        id: policySettings.id,
        policyName: policySettings.policyName,
        policyType: policySettings.policyType,
        settingName: policySettings.settingName,
        settingValue: policySettings.settingValue,
        lastSyncedAt: policySettings.lastSyncedAt,
      })
      .from(policySettings)
      .where(
        and(
          eq(policySettings.tenantId, tenantId), // CRITICAL: Tenant isolation
          ne(policySettings.settingValue, 'null'), // Filter out string "null"
          ne(policySettings.settingValue, ''), // Filter out empty strings
          isNotNull(policySettings.settingValue), // Filter out NULL values
          or(
            ilike(policySettings.settingName, searchPattern),
            ilike(policySettings.settingValue, searchPattern)
          )
        )
      )
      .orderBy(policySettings.settingName)
      .limit(safeLimit);

    return {
      success: true,
      data: results,
      totalCount: results.length,
    };
  } catch (error) {
    console.error('Search failed:', error);
    return { success: false, error: 'Search failed' };
  }
}

/**
 * Get a single policy setting by ID
 * 
 * **Security**: Enforces tenant isolation with explicit WHERE tenantId filter
 * 
 * @param id - Policy setting ID
 * @returns Policy setting if found and belongs to user's tenant
 */
export async function getPolicySettingById(
  id: string
): Promise<GetSettingResult> {
  try {
    const { session } = await getUserAuth();
    
    // T017: Explicit security check
    if (!session?.user) {
      return { success: false, error: 'Unauthorized' };
    }

    // T017: Explicit security check
    const tenantId = session.user.tenantId;
    if (!tenantId) {
      return { success: false, error: 'Tenant not found' };
    }

    // T017: Query filtered by tenantId FIRST for security
    const [result] = await db
      .select()
      .from(policySettings)
      .where(
        and(
          eq(policySettings.tenantId, tenantId), // CRITICAL: Tenant isolation
          eq(policySettings.id, id)
        )
      )
      .limit(1);

    if (!result) {
      return { success: false, error: 'Policy setting not found' };
    }

    return {
      success: true,
      data: result,
    };
  } catch (error) {
    console.error('Get policy setting failed:', error);
    return { success: false, error: 'Failed to fetch policy setting' };
  }
}

/**
 * Get recent policy settings sorted by last sync date
 * 
 * **Security**: Enforces tenant isolation with explicit WHERE tenantId filter
 * 
 * @param limit - Maximum number of results (1-100, default 50)
 * @returns Recent policy settings for user's tenant
 */
export async function getRecentPolicySettings(
  limit: number = 50
): Promise<RecentSettingsResult> {
  try {
    const { session } = await getUserAuth();
    
    // T017: Explicit security check
    if (!session?.user) {
      return { success: false, error: 'Unauthorized' };
    }

    // T017: Explicit security check
    const tenantId = session.user.tenantId;
    if (!tenantId) {
      return { success: false, error: 'Tenant not found' };
    }

    // Clamp limit between 1 and 100
    const safeLimit = Math.max(1, Math.min(100, limit));

    // T017: Query filtered by tenantId for security
    const results = await db
      .select({
        id: policySettings.id,
        policyName: policySettings.policyName,
        policyType: policySettings.policyType,
        settingName: policySettings.settingName,
        settingValue: policySettings.settingValue,
        lastSyncedAt: policySettings.lastSyncedAt,
      })
      .from(policySettings)
      .where(eq(policySettings.tenantId, tenantId)) // CRITICAL: Tenant isolation
      .orderBy(desc(policySettings.lastSyncedAt))
      .limit(safeLimit);

    return {
      success: true,
      data: results,
    };
  } catch (error) {
    console.error('Get recent settings failed:', error);
    return { success: false, error: 'Failed to fetch recent settings' };
  }
}

/**
 * Get all policy settings for the current user's tenant
 * 
 * **Security**: Enforces tenant isolation with explicit WHERE tenantId filter
 * 
 * @returns All policy settings for user's tenant
 */
export async function getAllPolicySettings(): Promise<AllSettingsResult> {
  try {
    const { session } = await getUserAuth();
    
    // T017: Explicit security check
    if (!session?.user) {
      return { success: false, error: 'Unauthorized' };
    }

    // T017: Explicit security check
    const tenantId = session.user.tenantId;
    if (!tenantId) {
      return { success: false, error: 'Tenant not found' };
    }

    // T017: Query filtered by tenantId for security
    const results = await db
      .select({
        id: policySettings.id,
        policyName: policySettings.policyName,
        policyType: policySettings.policyType,
        settingName: policySettings.settingName,
        settingValue: policySettings.settingValue,
        lastSyncedAt: policySettings.lastSyncedAt,
      })
      .from(policySettings)
      .where(eq(policySettings.tenantId, tenantId)) // CRITICAL: Tenant isolation
      .orderBy(desc(policySettings.lastSyncedAt));

    return {
      success: true,
      data: results,
      totalCount: results.length,
    };
  } catch (error) {
    console.error('Get all settings failed:', error);
    return { success: false, error: 'Failed to fetch settings' };
  }
}

/**
 * TEMPORARY: Seed test data for the current user's tenant
 * This is a development helper to populate realistic policy settings
 */
export async function seedMyTenantData(): Promise<{
  success: boolean;
  error?: string;
  message?: string;
}> {
  try {
    const { session } = await getUserAuth();

    if (!session?.user) {
      return { success: false, error: 'Unauthorized' };
    }

    const tenantId = session.user.tenantId;
    if (!tenantId) {
      return { success: false, error: 'Tenant ID not found in session' };
    }

    // Create 5 realistic policy settings for the user's tenant
    const seedData = [
      {
        tenantId,
        policyName: 'Windows 10 Security Baseline',
        policyType: 'deviceConfiguration' as const,
        settingName: 'USB.BlockExternalDevices',
        settingValue: 'enabled',
        graphPolicyId: `seed-${tenantId}-policy-001`,
      },
      {
        tenantId,
        policyName: 'BitLocker Compliance Policy',
        policyType: 'compliancePolicy' as const,
        settingName: 'BitLocker.RequireEncryption',
        settingValue: 'true',
        graphPolicyId: `seed-${tenantId}-policy-002`,
      },
      {
        tenantId,
        policyName: 'Camera and Microphone Restrictions',
        policyType: 'deviceConfiguration' as const,
        settingName: 'Camera.DisableCamera',
        settingValue: 'false',
        graphPolicyId: `seed-${tenantId}-policy-003`,
      },
      {
        tenantId,
        policyName: 'Windows Defender Configuration',
        policyType: 'endpointSecurity' as const,
        settingName: 'Defender.EnableRealTimeProtection',
        settingValue: 'enabled',
        graphPolicyId: `seed-${tenantId}-policy-004`,
      },
      {
        tenantId,
        policyName: 'Windows Update for Business',
        policyType: 'windowsUpdateForBusiness' as const,
        settingName: 'WindowsUpdate.DeferFeatureUpdatesPeriodInDays',
        settingValue: '30',
        graphPolicyId: `seed-${tenantId}-policy-005`,
      },
    ];

    // Insert all seed data
    for (const data of seedData) {
      await db.insert(policySettings).values({
        ...data,
        lastSyncedAt: new Date(),
      });
    }

    return {
      success: true,
      message: `Successfully seeded 5 policy settings for tenant ${tenantId}`,
    };
  } catch (error) {
    console.error('Seed data failed:', error);
    return { success: false, error: 'Failed to seed data' };
  }
}

/**
 * Trigger manual policy sync via BullMQ worker
 * 
 * **Security**: This function enforces tenant isolation by:
 * 1. Validating user session via getUserAuth()
 * 2. Extracting tenantId from session
 * 3. Enqueuing a job with only the authenticated user's tenantId
 * 
 * @returns Success/error result with job ID
 */
export async function triggerPolicySync(): Promise<{ success: boolean; message?: string; error?: string; jobId?: string }> {
  try {
    const { session } = await getUserAuth();

    if (!session?.user) {
      return { success: false, error: 'Not authenticated' };
    }

    const tenantId = session.user.tenantId;
    if (!tenantId) {
      return { success: false, error: 'No tenant ID found in session' };
    }

    // Enqueue sync job to BullMQ
    const job = await syncQueue.add('sync-tenant', {
      tenantId,
      source: 'manual_trigger',
      triggeredAt: new Date().toISOString(),
      triggeredBy: session.user.email || session.user.id,
    });

    return {
      success: true,
      message: `Policy sync queued successfully (Job #${job.id})`,
      jobId: job.id,
    };
  } catch (error) {
    console.error('Failed to trigger policy sync:', error);
    return {
      success: false,
      error: 'Failed to queue sync job. Please try again later.',
    };
  }
}