import { ApprovalLevel } from '@models/ApprovalLevel';
import { WorkflowRequest } from '@models/WorkflowRequest';
import { Participant } from '@models/Participant';
import { TatAlert } from '@models/TatAlert';
import { ApprovalAction } from '../types/approval.types';
import { ApprovalStatus, WorkflowStatus } from '../types/common.types';
import { calculateTATPercentage } from '@utils/helpers';
import { calculateElapsedWorkingHours } from '@utils/tatTimeUtils';
import logger, { logWorkflowEvent, logAIEvent } from '@utils/logger';
import { Op } from 'sequelize';
import { notificationService } from './notification.service';
import { activityService } from './activity.service';
import { tatSchedulerService } from './tatScheduler.service';
import { emitToRequestRoom } from '../realtime/socket';
import { DealerClaimService } from './dealerClaim.service';

export class ApprovalService {
  async approveLevel(levelId: string, action: ApprovalAction, _userId: string, requestMetadata?: { ipAddress?: string | null; userAgent?: string | null }): Promise<ApprovalLevel | null> {
    try {
      const level = await ApprovalLevel.findByPk(levelId);
      if (!level) return null;

      // Get workflow to determine priority for working hours calculation
      const wf = await WorkflowRequest.findByPk(level.requestId);
      if (!wf) return null;
      
      const priority = ((wf as any)?.priority || 'standard').toString().toLowerCase();
      const isPaused = (wf as any).isPaused || (level as any).isPaused;

      // If paused, resume automatically when approving/rejecting (requirement 3.6)
      if (isPaused) {
        const { pauseService } = await import('./pause.service');
        try {
          await pauseService.resumeWorkflow(level.requestId, _userId);
          logger.info(`[Approval] Auto-resumed paused workflow ${level.requestId} when ${action.action === 'APPROVE' ? 'approving' : 'rejecting'}`);
        } catch (pauseError) {
          logger.warn(`[Approval] Failed to auto-resume paused workflow:`, pauseError);
          // Continue with approval/rejection even if resume fails
        }
      }

      const now = new Date();
      
      // Calculate elapsed hours using working hours logic (with pause handling)
      // Case 1: Level is currently paused (isPaused = true)
      // Case 2: Level was paused and resumed (isPaused = false but pauseElapsedHours and pauseResumeDate exist)
      const isPausedLevel = (level as any).isPaused;
      const wasResumed = !isPausedLevel && 
        (level as any).pauseElapsedHours !== null && 
        (level as any).pauseElapsedHours !== undefined &&
        (level as any).pauseResumeDate !== null;
      
      const pauseInfo = isPausedLevel ? {
        // Level is currently paused - return frozen elapsed hours at pause time
        isPaused: true,
        pausedAt: (level as any).pausedAt,
        pauseElapsedHours: (level as any).pauseElapsedHours,
        pauseResumeDate: (level as any).pauseResumeDate
      } : wasResumed ? {
        // Level was paused but has been resumed - add pre-pause elapsed hours + time since resume
        isPaused: false,
        pausedAt: null,
        pauseElapsedHours: Number((level as any).pauseElapsedHours), // Pre-pause elapsed hours
        pauseResumeDate: (level as any).pauseResumeDate // Actual resume timestamp
      } : undefined;
      
      const elapsedHours = await calculateElapsedWorkingHours(
        level.levelStartTime || level.createdAt, 
        now, 
        priority,
        pauseInfo
      );
      const tatPercentage = calculateTATPercentage(elapsedHours, level.tatHours);

      const updateData = {
        status: action.action === 'APPROVE' ? ApprovalStatus.APPROVED : ApprovalStatus.REJECTED,
        actionDate: now,
        levelEndTime: now,
        elapsedHours,
        tatPercentageUsed: tatPercentage,
        comments: action.comments,
        rejectionReason: action.rejectionReason
      };

      const updatedLevel = await level.update(updateData);

      // Cancel TAT jobs for the current level since it's been actioned
      try {
        await tatSchedulerService.cancelTatJobs(level.requestId, level.levelId);
        logger.info(`[Approval] TAT jobs cancelled for level ${level.levelId}`);
      } catch (tatError) {
        logger.error(`[Approval] Failed to cancel TAT jobs:`, tatError);
        // Don't fail the approval if TAT cancellation fails
      }

      // Update TAT alerts for this level to mark completion status
      try {
        const wasOnTime = elapsedHours <= level.tatHours;
        await TatAlert.update(
          {
            wasCompletedOnTime: wasOnTime,
            completionTime: now
          },
          {
            where: { levelId: level.levelId }
          }
        );
        logger.info(`[Approval] TAT alerts updated for level ${level.levelId} - Completed ${wasOnTime ? 'on time' : 'late'}`);
      } catch (tatAlertError) {
        logger.error(`[Approval] Failed to update TAT alerts:`, tatAlertError);
        // Don't fail the approval if TAT alert update fails
      }

      // Handle approval - move to next level or close workflow (wf already loaded above)
      if (action.action === 'APPROVE') {
        if (level.isFinalApprover) {
          // Final approver - close workflow as APPROVED
          await WorkflowRequest.update(
            { 
              status: WorkflowStatus.APPROVED, 
              closureDate: now,
              currentLevel: (level.levelNumber || 0) + 1
            },
            { where: { requestId: level.requestId } }
          );
          logWorkflowEvent('approved', level.requestId, {
            level: level.levelNumber,
            isFinalApproval: true,
            status: 'APPROVED',
          });
          
          // Log final approval activity first (so it's included in AI context)
          activityService.log({
            requestId: level.requestId,
            type: 'approval',
            user: { userId: level.approverId, name: level.approverName },
            timestamp: new Date().toISOString(),
            action: 'Approved',
            details: `Request approved and finalized by ${level.approverName || level.approverEmail}. Awaiting conclusion remark from initiator.`,
            ipAddress: requestMetadata?.ipAddress || undefined,
            userAgent: requestMetadata?.userAgent || undefined
          });
          
          // Generate AI conclusion remark ASYNCHRONOUSLY (don't wait)
          // This runs in the background without blocking the approval response
          (async () => {
            try {
              const { aiService } = await import('./ai.service');
              const { ConclusionRemark } = await import('@models/index');
              const { ApprovalLevel } = await import('@models/ApprovalLevel');
              const { WorkNote } = await import('@models/WorkNote');
              const { Document } = await import('@models/Document');
              const { Activity } = await import('@models/Activity');
              const { getConfigValue } = await import('./configReader.service');
              
              // Check if AI features and remark generation are enabled in admin config
              const aiEnabled = (await getConfigValue('AI_ENABLED', 'true'))?.toLowerCase() === 'true';
              const remarkGenerationEnabled = (await getConfigValue('AI_REMARK_GENERATION_ENABLED', 'true'))?.toLowerCase() === 'true';
              
              if (aiEnabled && remarkGenerationEnabled && aiService.isAvailable()) {
                logAIEvent('request', {
                  requestId: level.requestId,
                  action: 'conclusion_generation_started',
                });
                
                // Gather context for AI generation
                const approvalLevels = await ApprovalLevel.findAll({
                  where: { requestId: level.requestId },
                  order: [['levelNumber', 'ASC']]
                });

                const workNotes = await WorkNote.findAll({
                  where: { requestId: level.requestId },
                  order: [['createdAt', 'ASC']],
                  limit: 20
                });

                const documents = await Document.findAll({
                  where: { requestId: level.requestId },
                  order: [['uploadedAt', 'DESC']]
                });

                const activities = await Activity.findAll({
                  where: { requestId: level.requestId },
                  order: [['createdAt', 'ASC']],
                  limit: 50
                });

                // Build context object
                const context = {
                  requestTitle: (wf as any).title,
                  requestDescription: (wf as any).description,
                  requestNumber: (wf as any).requestNumber,
                  priority: (wf as any).priority,
                  approvalFlow: approvalLevels.map((l: any) => {
                    const tatPercentage = l.tatPercentageUsed !== undefined && l.tatPercentageUsed !== null 
                      ? Number(l.tatPercentageUsed) 
                      : (l.elapsedHours && l.tatHours ? (Number(l.elapsedHours) / Number(l.tatHours)) * 100 : 0);
                    return {
                      levelNumber: l.levelNumber,
                      approverName: l.approverName,
                      status: l.status,
                      comments: l.comments,
                      actionDate: l.actionDate,
                      tatHours: Number(l.tatHours || 0),
                      elapsedHours: Number(l.elapsedHours || 0),
                      tatPercentageUsed: tatPercentage
                    };
                  }),
                  workNotes: workNotes.map((note: any) => ({
                    userName: note.userName,
                    message: note.message,
                    createdAt: note.createdAt
                  })),
                  documents: documents.map((doc: any) => ({
                    fileName: doc.originalFileName || doc.fileName,
                    uploadedBy: doc.uploadedBy,
                    uploadedAt: doc.uploadedAt
                  })),
                  activities: activities.map((activity: any) => ({
                    type: activity.activityType,
                    action: activity.activityDescription,
                    details: activity.activityDescription,
                    timestamp: activity.createdAt
                  }))
                };

                const aiResult = await aiService.generateConclusionRemark(context);
                
                // Save to database
                await ConclusionRemark.create({
                  requestId: level.requestId,
                  aiGeneratedRemark: aiResult.remark,
                  aiModelUsed: aiResult.provider,
                  aiConfidenceScore: aiResult.confidence,
                  finalRemark: null,
                  editedBy: null,
                  isEdited: false,
                  editCount: 0,
                  approvalSummary: {
                    totalLevels: approvalLevels.length,
                    approvedLevels: approvalLevels.filter((l: any) => l.status === 'APPROVED').length,
                    averageTatUsage: approvalLevels.reduce((sum: number, l: any) => 
                      sum + Number(l.tatPercentageUsed || 0), 0) / (approvalLevels.length || 1)
                  },
                  documentSummary: {
                    totalDocuments: documents.length,
                    documentNames: documents.map((d: any) => d.originalFileName || d.fileName)
                  },
                  keyDiscussionPoints: aiResult.keyPoints,
                  generatedAt: new Date(),
                  finalizedAt: null
                } as any);
                
                logAIEvent('response', {
                  requestId: level.requestId,
                  action: 'conclusion_generation_completed',
                });
                
                // Log activity
                activityService.log({
                  requestId: level.requestId,
                  type: 'ai_conclusion_generated',
                  user: { userId: 'system', name: 'System' },
                  timestamp: new Date().toISOString(),
                  action: 'AI Conclusion Generated',
                  details: 'AI-powered conclusion remark generated for review by initiator',
                  ipAddress: undefined, // System-generated, no IP
                  userAgent: undefined  // System-generated, no user agent
                });
              } else {
                // Log why AI generation was skipped
                if (!aiEnabled) {
                  logger.info(`[Approval] AI features disabled in admin config, skipping conclusion generation for ${level.requestId}`);
                } else if (!remarkGenerationEnabled) {
                  logger.info(`[Approval] AI remark generation disabled in admin config, skipping for ${level.requestId}`);
                } else if (!aiService.isAvailable()) {
                  logger.warn(`[Approval] AI service unavailable for ${level.requestId}, skipping conclusion generation`);
                }
              }
              
              // Auto-generate RequestSummary after final approval (system-level generation)
              // This makes the summary immediately available when user views the approved request
              try {
                const { summaryService } = await import('./summary.service');
                const summary = await summaryService.createSummary(level.requestId, 'system', { 
                  isSystemGeneration: true 
                });
                logger.info(`[Approval] ✅ Auto-generated summary ${(summary as any).summaryId} for approved request ${level.requestId}`);
                
                // Log summary generation activity
                activityService.log({
                  requestId: level.requestId,
                  type: 'summary_generated',
                  user: { userId: 'system', name: 'System' },
                  timestamp: new Date().toISOString(),
                  action: 'Summary Auto-Generated',
                  details: 'Request summary auto-generated after final approval',
                  ipAddress: undefined,
                  userAgent: undefined
                });
              } catch (summaryError: any) {
                // Log but don't fail - initiator can regenerate later
                logger.error(`[Approval] Failed to auto-generate summary for ${level.requestId}:`, summaryError.message);
              }
              
            } catch (aiError) {
              logAIEvent('error', {
                requestId: level.requestId,
                action: 'conclusion_generation_failed',
                error: aiError,
              });
              // Silent failure - initiator can write manually
              
              // Still try to generate summary even if AI conclusion failed
              try {
                const { summaryService } = await import('./summary.service');
                const summary = await summaryService.createSummary(level.requestId, 'system', { 
                  isSystemGeneration: true 
                });
                logger.info(`[Approval] ✅ Auto-generated summary ${(summary as any).summaryId} for approved request ${level.requestId} (without AI conclusion)`);
              } catch (summaryError: any) {
                logger.error(`[Approval] Failed to auto-generate summary for ${level.requestId}:`, summaryError.message);
              }
            }
          })().catch(err => {
            // Catch any unhandled promise rejections
            logger.error(`[Approval] Unhandled error in background AI generation:`, err);
          });
          
          // Notify initiator and all participants (including spectators) about approval
          // Spectators are CC'd for transparency, similar to email CC
          if (wf) {
            const participants = await Participant.findAll({ 
              where: { requestId: level.requestId } 
            });
            const targetUserIds = new Set<string>();
            targetUserIds.add((wf as any).initiatorId);
            for (const p of participants as any[]) {
              targetUserIds.add(p.userId); // Includes spectators
            }
            
            // Send notification to initiator (with action required)
            const initiatorId = (wf as any).initiatorId;
            await notificationService.sendToUsers([initiatorId], {
              title: `Request Approved - Closure Pending`,
              body: `Your request "${(wf as any).title}" has been fully approved. Please review and finalize the conclusion remark to close the request.`,
              requestNumber: (wf as any).requestNumber,
              requestId: level.requestId,
              url: `/request/${(wf as any).requestNumber}`,
              type: 'approval_pending_closure',
              priority: 'HIGH',
              actionRequired: true
            });
            
            // Send notification to all participants/spectators (for transparency, no action required)
            const participantUserIds = Array.from(targetUserIds).filter(id => id !== initiatorId);
            if (participantUserIds.length > 0) {
              await notificationService.sendToUsers(participantUserIds, {
                title: `Request Approved`,
                body: `Request "${(wf as any).title}" has been fully approved. The initiator will finalize the conclusion remark to close the request.`,
                requestNumber: (wf as any).requestNumber,
                requestId: level.requestId,
                url: `/request/${(wf as any).requestNumber}`,
                type: 'approval_pending_closure',
                priority: 'MEDIUM',
                actionRequired: false
              });
            }
            
            logger.info(`[Approval] ✅ Final approval complete for ${level.requestId}. Initiator and ${participants.length} participant(s) notified.`);
          }
        } else {
          // Not final - move to next level
          // Check if workflow is paused - if so, don't advance
          if ((wf as any).isPaused || (wf as any).status === 'PAUSED') {
            logger.warn(`[Approval] Cannot advance workflow ${level.requestId} - workflow is paused`);
            throw new Error('Cannot advance workflow - workflow is currently paused. Please resume the workflow first.');
          }
          
          const nextLevelNumber = (level.levelNumber || 0) + 1;
          const nextLevel = await ApprovalLevel.findOne({
            where: {
              requestId: level.requestId,
              levelNumber: nextLevelNumber
            }
          });

          if (nextLevel) {
            // Check if next level is paused - if so, don't activate it
            if ((nextLevel as any).isPaused || (nextLevel as any).status === 'PAUSED') {
              logger.warn(`[Approval] Cannot activate next level ${nextLevelNumber} - level is paused`);
              throw new Error('Cannot activate next level - the next approval level is currently paused. Please resume it first.');
            }
            
            // Activate next level
            await nextLevel.update({
              status: ApprovalStatus.IN_PROGRESS,
              levelStartTime: now,
              tatStartTime: now
            });
            
            // Schedule TAT jobs for the next level
            try {
              // Get workflow priority for TAT calculation
              const workflowPriority = (wf as any)?.priority || 'STANDARD';
              
              await tatSchedulerService.scheduleTatJobs(
                level.requestId,
                (nextLevel as any).levelId,
                (nextLevel as any).approverId,
                Number((nextLevel as any).tatHours),
                now,
                workflowPriority  // Pass workflow priority (EXPRESS = 24/7, STANDARD = working hours)
              );
              logger.info(`[Approval] TAT jobs scheduled for next level ${nextLevelNumber} (Priority: ${workflowPriority})`);
            } catch (tatError) {
              logger.error(`[Approval] Failed to schedule TAT jobs for next level:`, tatError);
              // Don't fail the approval if TAT scheduling fails
            }
            
            // Update workflow current level
            await WorkflowRequest.update(
              { currentLevel: nextLevelNumber },
              { where: { requestId: level.requestId } }
            );
            
            logger.info(`Approved level ${level.levelNumber}. Activated next level ${nextLevelNumber} for workflow ${level.requestId}`);
            
            // Check if this is Department Lead approval in a claim management workflow
            // Activity Creation is now an activity log only, not an approval step
            const workflowType = (wf as any)?.workflowType;
            const isClaimManagement = workflowType === 'CLAIM_MANAGEMENT';
            
            // Check if current level is Department Lead (by levelName, not hardcoded step number)
            const currentLevelName = (level.levelName || '').toLowerCase();
            const isDeptLeadApproval = currentLevelName.includes('department lead') || level.levelNumber === 3;
            
            // Check if current level is Requestor Claim Approval (Step 5, was Step 6)
            const currentLevelNameForStep5 = (level.levelName || '').toLowerCase();
            const isRequestorClaimApproval = currentLevelNameForStep5.includes('requestor') && 
                                           (currentLevelNameForStep5.includes('claim') || currentLevelNameForStep5.includes('approval')) ||
                                           level.levelNumber === 5;
            
            if (isClaimManagement && isDeptLeadApproval) {
              // Activity Creation is now an activity log only - process it automatically
              logger.info(`[Approval] Department Lead approved for claim management workflow. Processing Activity Creation as activity log.`);
              try {
                const dealerClaimService = new DealerClaimService();
                await dealerClaimService.processActivityCreation(level.requestId);
                logger.info(`[Approval] Activity Creation activity logged for request ${level.requestId}`);
              } catch (activityError) {
                logger.error(`[Approval] Error processing Activity Creation activity for request ${level.requestId}:`, activityError);
                // Don't fail the Department Lead approval if Activity Creation logging fails - log and continue
              }
            } else if (isClaimManagement && isRequestorClaimApproval) {
              // E-Invoice Generation is now an activity log only - will be logged when invoice is generated via DMS webhook
              logger.info(`[Approval] Requestor Claim Approval approved for claim management workflow. E-Invoice generation will be logged as activity when DMS webhook is received.`);
            } 
            
            if (wf && nextLevel) {
              // Normal flow - notify next approver (skip for auto-steps)
              // Check if it's an auto-step by checking approverEmail or levelName
              // Note: Activity Creation, E-Invoice Generation, and Credit Note Confirmation are no longer approval steps
              const isAutoStep = (nextLevel as any).approverEmail === 'system@royalenfield.com' 
                || (nextLevel as any).approverName === 'System Auto-Process';
              
              // Log approval activity
              activityService.log({
                requestId: level.requestId,
                type: 'approval',
                user: { userId: level.approverId, name: level.approverName },
                timestamp: new Date().toISOString(),
                action: 'Approved',
                details: `Request approved and forwarded to ${(nextLevel as any).approverName || (nextLevel as any).approverEmail} by ${level.approverName || level.approverEmail}`,
                ipAddress: requestMetadata?.ipAddress || undefined,
                userAgent: requestMetadata?.userAgent || undefined
              });

              // Log assignment activity for next level (when it becomes active)
              // IMPORTANT: Skip notifications and assignment logging for system/auto-steps
              // System steps are any step with system@royalenfield.com
              // Note: Activity Creation, E-Invoice Generation, and Credit Note Confirmation are now activity logs only, not approval steps
              // These steps are processed automatically and should NOT trigger notifications
              if (!isAutoStep && (nextLevel as any).approverId && (nextLevel as any).approverId !== 'system') {
                // Additional checks: ensure approverEmail and approverName are not system-related
                // This prevents notifications to system accounts even if they pass other checks
                const approverEmail = (nextLevel as any).approverEmail || '';
                const approverName = (nextLevel as any).approverName || '';
                const isSystemEmail = approverEmail.toLowerCase() === 'system@royalenfield.com' 
                  || approverEmail.toLowerCase().includes('system');
                const isSystemName = approverName.toLowerCase() === 'system auto-process'
                  || approverName.toLowerCase().includes('system');
                
                // EXCLUDE all system-related steps from notifications
                // Only send notifications to real users, NOT system processes
                if (!isSystemEmail && !isSystemName) {
                  // Send notification to next approver (only for real users, not system processes)
                  // This will send both in-app and email notifications
                  const nextApproverId = (nextLevel as any).approverId;
                  const nextApproverName = (nextLevel as any).approverName || (nextLevel as any).approverEmail || 'approver';
                  
                  logger.info(`[Approval] Sending assignment notification to next approver: ${nextApproverName} (${nextApproverId}) at level ${nextLevelNumber} for request ${(wf as any).requestNumber}`);
                  
                  await notificationService.sendToUsers([ nextApproverId ], {
                    title: `Action required: ${(wf as any).requestNumber}`,
                    body: `${(wf as any).title}`,
                    requestNumber: (wf as any).requestNumber,
                    requestId: (wf as any).requestId,
                    url: `/request/${(wf as any).requestNumber}`,
                    type: 'assignment',
                    priority: 'HIGH',
                    actionRequired: true
                  });

                  logger.info(`[Approval] Assignment notification sent successfully to ${nextApproverName} for level ${nextLevelNumber}`);

                  // Log assignment activity for the next approver
                  activityService.log({
                    requestId: level.requestId,
                    type: 'assignment',
                    user: { userId: level.approverId, name: level.approverName },
                    timestamp: new Date().toISOString(),
                    action: 'Assigned to approver',
                    details: `Request assigned to ${nextApproverName} for ${(nextLevel as any).levelName || `level ${nextLevelNumber}`}`,
                    ipAddress: requestMetadata?.ipAddress || undefined,
                    userAgent: requestMetadata?.userAgent || undefined
                  });
                } else {
                  logger.info(`[Approval] Skipping notification for system process: ${approverEmail} at level ${nextLevelNumber}`);
                }
              } else {
                logger.info(`[Approval] Skipping notification for auto-step at level ${nextLevelNumber}`);
              }
              
              // Notify initiator when dealer submits documents (Dealer Proposal or Dealer Completion Documents approval in claim management)
              const workflowType = (wf as any)?.workflowType;
              const isClaimManagement = workflowType === 'CLAIM_MANAGEMENT';
              const levelName = (level.levelName || '').toLowerCase();
              const isDealerProposalApproval = levelName.includes('dealer') && levelName.includes('proposal') || level.levelNumber === 1;
              const isDealerCompletionApproval = levelName.includes('dealer') && (levelName.includes('completion') || levelName.includes('documents')) || level.levelNumber === 5;
              
              if (isClaimManagement && (isDealerProposalApproval || isDealerCompletionApproval) && (wf as any).initiatorId) {
                const stepMessage = isDealerProposalApproval 
                  ? 'Dealer proposal has been submitted and is now under review.'
                  : 'Dealer completion documents have been submitted and are now under review.';
                
                await notificationService.sendToUsers([(wf as any).initiatorId], {
                  title: isDealerProposalApproval ? 'Proposal Submitted' : 'Completion Documents Submitted',
                  body: `Your claim request "${(wf as any).title}" - ${stepMessage}`,
                  requestNumber: (wf as any).requestNumber,
                  requestId: (wf as any).requestId,
                  url: `/request/${(wf as any).requestNumber}`,
                  type: 'approval',
                  priority: 'MEDIUM',
                  actionRequired: false
                });
                
                logger.info(`[Approval] Sent notification to initiator for ${isDealerProposalApproval ? 'Dealer Proposal Submission' : 'Dealer Completion Documents'} approval in claim management workflow`);
              }
            }
          } else {
            // No next level found but not final approver - this shouldn't happen
            logger.warn(`No next level found for workflow ${level.requestId} after approving level ${level.levelNumber}`);
            await WorkflowRequest.update(
              { 
                status: WorkflowStatus.APPROVED, 
                closureDate: now,
                currentLevel: nextLevelNumber
              },
              { where: { requestId: level.requestId } }
            );
            if (wf) {
              await notificationService.sendToUsers([ (wf as any).initiatorId ], {
                title: `Approved: ${(wf as any).requestNumber}`,
                body: `${(wf as any).title}`,
                requestNumber: (wf as any).requestNumber,
                url: `/request/${(wf as any).requestNumber}`
              });
              activityService.log({
                requestId: level.requestId,
                type: 'approval',
                user: { userId: level.approverId, name: level.approverName },
                timestamp: new Date().toISOString(),
                action: 'Approved',
                details: `Request approved and finalized by ${level.approverName || level.approverEmail}`,
                ipAddress: requestMetadata?.ipAddress || undefined,
                userAgent: requestMetadata?.userAgent || undefined
              });
            }
          }
        }
      } else if (action.action === 'REJECT') {
        // Rejection - mark workflow as REJECTED (closure will happen when initiator finalizes conclusion)
        await WorkflowRequest.update(
          { 
            status: WorkflowStatus.REJECTED
            // Note: closureDate will be set when initiator finalizes the conclusion
          },
          { where: { requestId: level.requestId } }
        );

        // Mark all pending levels as skipped
        await ApprovalLevel.update(
          { 
            status: ApprovalStatus.SKIPPED,
            levelEndTime: now
          },
          { 
            where: { 
              requestId: level.requestId,
              status: ApprovalStatus.PENDING,
              levelNumber: { [Op.gt]: level.levelNumber } 
            } 
          }
        );

        logWorkflowEvent('rejected', level.requestId, {
          level: level.levelNumber,
          status: 'REJECTED',
          message: 'Awaiting closure from initiator',
        });
        
        // Log rejection activity first (so it's included in AI context)
        if (wf) {
          activityService.log({
            requestId: level.requestId,
            type: 'rejection',
            user: { userId: level.approverId, name: level.approverName },
            timestamp: new Date().toISOString(),
            action: 'Rejected',
            details: `Request rejected by ${level.approverName || level.approverEmail}. Reason: ${action.rejectionReason || action.comments || 'No reason provided'}. Awaiting closure from initiator.`,
            ipAddress: requestMetadata?.ipAddress || undefined,
            userAgent: requestMetadata?.userAgent || undefined
          });
        }
        
        // Notify initiator and all participants
        if (wf) {
          const participants = await Participant.findAll({ where: { requestId: level.requestId } });
          const targetUserIds = new Set<string>();
          targetUserIds.add((wf as any).initiatorId);
          for (const p of participants as any[]) {
            targetUserIds.add(p.userId);
          }
          await notificationService.sendToUsers(Array.from(targetUserIds), {
            title: `Rejected: ${(wf as any).requestNumber}`,
            body: `${(wf as any).title}`,
            requestNumber: (wf as any).requestNumber,
            url: `/request/${(wf as any).requestNumber}`
          });
        }
        
        // Generate AI conclusion remark ASYNCHRONOUSLY for rejected requests (similar to approved)
        // This runs in the background without blocking the rejection response
        (async () => {
          try {
            const { aiService } = await import('./ai.service');
            const { ConclusionRemark } = await import('@models/index');
            const { ApprovalLevel } = await import('@models/ApprovalLevel');
            const { WorkNote } = await import('@models/WorkNote');
            const { Document } = await import('@models/Document');
            const { Activity } = await import('@models/Activity');
            const { getConfigValue } = await import('./configReader.service');
            
            // Check if AI features and remark generation are enabled in admin config
            const aiEnabled = (await getConfigValue('AI_ENABLED', 'true'))?.toLowerCase() === 'true';
            const remarkGenerationEnabled = (await getConfigValue('AI_REMARK_GENERATION_ENABLED', 'true'))?.toLowerCase() === 'true';
            
            if (!aiEnabled || !remarkGenerationEnabled) {
              logger.info(`[Approval] AI conclusion generation skipped for rejected request ${level.requestId} (AI disabled)`);
              return;
            }
            
            // Check if AI service is available
            const { aiService: aiSvc } = await import('./ai.service');
            if (!aiSvc.isAvailable()) {
              logger.warn(`[Approval] AI service unavailable for rejected request ${level.requestId}`);
              return;
            }
            
            // Gather context for AI generation (similar to approved flow)
            const approvalLevels = await ApprovalLevel.findAll({
              where: { requestId: level.requestId },
              order: [['levelNumber', 'ASC']]
            });
            
            const workNotes = await WorkNote.findAll({
              where: { requestId: level.requestId },
              order: [['createdAt', 'ASC']],
              limit: 20
            });
            
            const documents = await Document.findAll({
              where: { requestId: level.requestId },
              order: [['uploadedAt', 'DESC']]
            });
            
            const activities = await Activity.findAll({
              where: { requestId: level.requestId },
              order: [['createdAt', 'ASC']],
              limit: 50
            });
            
            // Build context object (include rejection reason)
            const context = {
              requestTitle: (wf as any).title,
              requestDescription: (wf as any).description,
              requestNumber: (wf as any).requestNumber,
              priority: (wf as any).priority,
              rejectionReason: action.rejectionReason || action.comments || 'No reason provided',
              rejectedBy: level.approverName || level.approverEmail,
              approvalFlow: approvalLevels.map((l: any) => {
                const tatPercentage = l.tatPercentageUsed !== undefined && l.tatPercentageUsed !== null 
                  ? Number(l.tatPercentageUsed) 
                  : (l.elapsedHours && l.tatHours ? (Number(l.elapsedHours) / Number(l.tatHours)) * 100 : 0);
                return {
                  levelNumber: l.levelNumber,
                  approverName: l.approverName,
                  status: l.status,
                  comments: l.comments,
                  actionDate: l.actionDate,
                  tatHours: Number(l.tatHours || 0),
                  elapsedHours: Number(l.elapsedHours || 0),
                  tatPercentageUsed: tatPercentage
                };
              }),
              workNotes: workNotes.map((note: any) => ({
                userName: note.userName,
                message: note.message,
                createdAt: note.createdAt
              })),
              documents: documents.map((doc: any) => ({
                fileName: doc.originalFileName || doc.fileName,
                uploadedBy: doc.uploadedBy,
                uploadedAt: doc.uploadedAt
              })),
              activities: activities.map((activity: any) => ({
                type: activity.activityType,
                action: activity.activityDescription,
                details: activity.activityDescription,
                timestamp: activity.createdAt
              }))
            };
            
            logger.info(`[Approval] Generating AI conclusion for rejected request ${level.requestId}...`);
            
            // Generate AI conclusion (will adapt to rejection context)
            const aiResult = await aiSvc.generateConclusionRemark(context);
            
            // Create or update conclusion remark
            let conclusionInstance = await ConclusionRemark.findOne({ where: { requestId: level.requestId } });
            
            const conclusionData = {
              aiGeneratedRemark: aiResult.remark,
              aiModelUsed: aiResult.provider,
              aiConfidenceScore: aiResult.confidence,
              approvalSummary: {
                totalLevels: approvalLevels.length,
                rejectedLevel: level.levelNumber,
                rejectedBy: level.approverName || level.approverEmail,
                rejectionReason: action.rejectionReason || action.comments
              },
              documentSummary: {
                totalDocuments: documents.length,
                documentNames: documents.map((d: any) => d.originalFileName || d.fileName)
              },
              keyDiscussionPoints: aiResult.keyPoints,
              generatedAt: new Date()
            };
            
            if (conclusionInstance) {
              await conclusionInstance.update(conclusionData as any);
              logger.info(`[Approval] ✅ AI conclusion updated for rejected request ${level.requestId}`);
            } else {
              await ConclusionRemark.create({
                requestId: level.requestId,
                ...conclusionData,
                finalRemark: null,
                editedBy: null,
                isEdited: false,
                editCount: 0,
                finalizedAt: null
              } as any);
              logger.info(`[Approval] ✅ AI conclusion generated for rejected request ${level.requestId}`);
            }
          } catch (error: any) {
            logger.error(`[Approval] Failed to generate AI conclusion for rejected request ${level.requestId}:`, error);
            // Don't fail the rejection if AI generation fails
          }
        })();
      }

      logger.info(`Approval level ${levelId} ${action.action.toLowerCase()}ed`);
      
      // Emit real-time update to all users viewing this request
      emitToRequestRoom(level.requestId, 'request:updated', {
        requestId: level.requestId,
        requestNumber: (wf as any)?.requestNumber,
        action: action.action,
        levelNumber: level.levelNumber,
        timestamp: now.toISOString()
      });
      
      return updatedLevel;
    } catch (error) {
      logger.error(`Failed to ${action.action.toLowerCase()} level ${levelId}:`, error);
      throw new Error(`Failed to ${action.action.toLowerCase()} level`);
    }
  }

  async getCurrentApprovalLevel(requestId: string): Promise<ApprovalLevel | null> {
    try {
      return await ApprovalLevel.findOne({
        where: { requestId, status: ApprovalStatus.PENDING },
        order: [['levelNumber', 'ASC']]
      });
    } catch (error) {
      logger.error(`Failed to get current approval level for ${requestId}:`, error);
      throw new Error('Failed to get current approval level');
    }
  }

  async getApprovalLevels(requestId: string): Promise<ApprovalLevel[]> {
    try {
      return await ApprovalLevel.findAll({
        where: { requestId },
        order: [['levelNumber', 'ASC']]
      });
    } catch (error) {
      logger.error(`Failed to get approval levels for ${requestId}:`, error);
      throw new Error('Failed to get approval levels');
    }
  }
}