import { Component, OnInit, OnDestroy, ViewChild, ElementRef, AfterViewChecked } from '@angular/core';
import { CommonModule } from '@angular/common';
import { MatCardModule } from '@angular/material/card';
import { MatButtonModule } from '@angular/material/button';
import { MatIconModule } from '@angular/material/icon';
import { MatProgressSpinnerModule } from '@angular/material/progress-spinner';
import { MatDividerModule } from '@angular/material/divider';
import { MatChipsModule } from '@angular/material/chips';
import { MatSnackBar, MatSnackBarModule } from '@angular/material/snack-bar';
import { MatDialogRef, MAT_DIALOG_DATA } from '@angular/material/dialog';
import { Inject } from '@angular/core';
import { Subject, takeUntil } from 'rxjs';

import { ConversationManagerService, ConversationState, ConversationMessage } from '../../services/conversation-manager.service';
import { AudioStreamService } from '../../services/audio-stream.service';

@Component({
  selector: 'app-realtime-chat',
  standalone: true,
  imports: [
    CommonModule,
    MatCardModule,
    MatButtonModule,
    MatIconModule,
    MatProgressSpinnerModule,
    MatDividerModule,
    MatChipsModule,
    MatSnackBarModule
  ],
  template: `
    <mat-card class="realtime-chat-container">
      <mat-card-header>
        <mat-icon mat-card-avatar>voice_chat</mat-icon>
        <mat-card-title>Real-time Conversation</mat-card-title>
        <mat-card-subtitle>
          <mat-chip-listbox>
            <mat-chip [class.active]="currentState === state" 
                     *ngFor="let state of conversationStates">
              {{ getStateLabel(state) }}
            </mat-chip>
          </mat-chip-listbox>
        </mat-card-subtitle>
        <button mat-icon-button class="close-button" (click)="closeDialog()">
          <mat-icon>close</mat-icon>
        </button>
      </mat-card-header>

      <mat-divider></mat-divider>

      <mat-card-content>
        <!-- Error State -->
        <div class="error-banner" *ngIf="error">
          <mat-icon>error_outline</mat-icon>
          <span>{{ error }}</span>
          <button mat-icon-button (click)="retryConnection()">
            <mat-icon>refresh</mat-icon>
          </button>
        </div>

        <!-- Transcription Display -->
        <div class="transcription-area" *ngIf="currentTranscription">
          <div class="transcription-label">Dinleniyor...</div>
          <div class="transcription-text">{{ currentTranscription }}</div>
        </div>

        <!-- Chat Messages -->
        <div class="chat-messages" #scrollContainer>
          <div *ngFor="let msg of messages; trackBy: trackByIndex" 
               [class]="'message ' + msg.role">
            <mat-icon class="message-icon">
              {{ msg.role === 'user' ? 'person' : 'smart_toy' }}
            </mat-icon>
            <div class="message-content">
              <div class="message-text">{{ msg.text }}</div>
              <div class="message-time">{{ msg.timestamp | date:'HH:mm:ss' }}</div>
              <button *ngIf="msg.audioUrl" 
                      mat-icon-button 
                      (click)="playAudio(msg.audioUrl)"
                      class="audio-button"
                      [disabled]="isPlayingAudio">
                <mat-icon>{{ isPlayingAudio ? 'stop' : 'volume_up' }}</mat-icon>
              </button>
            </div>
          </div>
          
          <!-- Empty State -->
          <div class="empty-state" *ngIf="messages.length === 0 && !isConversationActive">
            <mat-icon>mic_off</mat-icon>
            <p>Konuşmaya başlamak için aşağıdaki butona tıklayın</p>
          </div>
        </div>

        <!-- Audio Visualizer -->
        <canvas #audioVisualizer 
                class="audio-visualizer" 
                width="600" 
                height="100"
                [class.active]="isRecording">
        </canvas>
      </mat-card-content>

      <mat-card-actions>
        <button mat-raised-button 
                color="primary" 
                (click)="toggleConversation()"
                [disabled]="!sessionId || loading">
          @if (loading) {
            <mat-spinner diameter="20"></mat-spinner>
          } @else {
            <mat-icon>{{ isConversationActive ? 'stop' : 'mic' }}</mat-icon>
            {{ isConversationActive ? 'Konuşmayı Bitir' : 'Konuşmaya Başla' }}
          }
        </button>

        <button mat-button 
                (click)="clearChat()"
                [disabled]="messages.length === 0">
          <mat-icon>clear</mat-icon>
          Temizle
        </button>
        
        <button mat-button 
                (click)="performBargeIn()"
                [disabled]="!isConversationActive || currentState === 'idle' || currentState === 'listening'">
          <mat-icon>pan_tool</mat-icon>
          Kesme (Barge-in)
        </button>
      </mat-card-actions>
    </mat-card>
  `,
  styles: [`
    .realtime-chat-container {
      max-width: 800px;
      margin: 20px auto;
      height: 80vh;
      display: flex;
      flex-direction: column;
      position: relative;
    }

    mat-card-header {
      position: relative;
      
      .close-button {
        position: absolute;
        top: 8px;
        right: 8px;
      }
    }

    .error-banner {
      background-color: #ffebee;
      color: #c62828;
      padding: 12px;
      border-radius: 4px;
      display: flex;
      align-items: center;
      gap: 8px;
      margin-bottom: 16px;
      
      mat-icon {
        font-size: 20px;
        width: 20px;
        height: 20px;
      }
      
      span {
        flex: 1;
      }
    }

    .transcription-area {
      background: #f5f5f5;
      padding: 16px;
      border-radius: 8px;
      margin-bottom: 16px;
      min-height: 60px;
      animation: pulse 2s infinite;
    }

    @keyframes pulse {
      0% { opacity: 1; }
      50% { opacity: 0.7; }
      100% { opacity: 1; }
    }

    .transcription-label {
      font-size: 12px;
      color: #666;
      margin-bottom: 4px;
    }

    .transcription-text {
      font-size: 16px;
      color: #333;
      min-height: 24px;
    }

    .chat-messages {
      flex: 1;
      overflow-y: auto;
      padding: 16px;
      background: #fafafa;
      border-radius: 8px;
      min-height: 200px;
      max-height: 400px;
    }

    .message {
      display: flex;
      align-items: flex-start;
      margin-bottom: 16px;
      animation: slideIn 0.3s ease-out;
    }

    @keyframes slideIn {
      from {
        opacity: 0;
        transform: translateY(10px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }

    .message.user {
      flex-direction: row-reverse;
    }

    .message-icon {
      margin: 0 8px;
      color: #666;
    }

    .message-content {
      max-width: 70%;
      background: white;
      padding: 12px 16px;
      border-radius: 12px;
      box-shadow: 0 1px 2px rgba(0,0,0,0.1);
      position: relative;
    }

    .message.user .message-content {
      background: #3f51b5;
      color: white;
    }

    .message-text {
      margin-bottom: 4px;
    }

    .message-time {
      font-size: 11px;
      opacity: 0.7;
    }

    .audio-button {
      margin-top: 8px;
    }

    .empty-state {
      text-align: center;
      padding: 60px 20px;
      color: #999;
      
      mat-icon {
        font-size: 48px;
        width: 48px;
        height: 48px;
        margin-bottom: 16px;
      }
    }

    .audio-visualizer {
      width: 100%;
      height: 100px;
      background: #333;
      border-radius: 8px;
      margin-top: 16px;
      opacity: 0.3;
      transition: opacity 0.3s;
    }

    .audio-visualizer.active {
      opacity: 1;
    }

    mat-chip {
      font-size: 12px;
    }

    mat-chip.active {
      background-color: #3f51b5 !important;
      color: white !important;
    }

    mat-card-actions {
      padding: 16px;
      display: flex;
      gap: 16px;
      justify-content: flex-start;
      
      mat-spinner {
        display: inline-block;
        margin-right: 8px;
      }
    }
  `]
})
export class RealtimeChatComponent implements OnInit, OnDestroy, AfterViewChecked {
  @ViewChild('scrollContainer') private scrollContainer!: ElementRef;
  @ViewChild('audioVisualizer') private audioVisualizer!: ElementRef<HTMLCanvasElement>;
  
  sessionId: string | null = null;
  projectName: string | null = null;
  isConversationActive = false;
  isRecording = false;
  isPlayingAudio = false;
  currentState: ConversationState = 'idle';
  currentTranscription = '';
  messages: ConversationMessage[] = [];
  error = '';
  loading = false;
  
  conversationStates: ConversationState[] = [
    'idle', 'listening', 'processing_stt', 'processing_llm', 'processing_tts', 'playing_audio'
  ];
  
  private destroyed$ = new Subject<void>();
  private shouldScrollToBottom = false;
  private animationId: number | null = null;
  private currentAudio: HTMLAudioElement | null = null;

  constructor(
    private conversationManager: ConversationManagerService,
    private audioService: AudioStreamService,
    private snackBar: MatSnackBar,
    public dialogRef: MatDialogRef<RealtimeChatComponent>,
    @Inject(MAT_DIALOG_DATA) public data: { sessionId: string; projectName?: string }
  ) {
    this.sessionId = data.sessionId;
    this.projectName = data.projectName || null;
  }

  ngOnInit(): void {
    // Check browser support
    if (!AudioStreamService.checkBrowserSupport()) {
      this.error = 'Tarayıcınız ses kaydını desteklemiyor. Lütfen modern bir tarayıcı kullanın.';
      this.snackBar.open(this.error, 'Close', {
        duration: 5000,
        panelClass: 'error-snackbar'
      });
      return;
    }
    
    // Check microphone permission
    this.checkMicrophonePermission();
    
    // Subscribe to conversation state
    this.conversationManager.currentState$.pipe(
      takeUntil(this.destroyed$)
    ).subscribe(state => {
      this.currentState = state;
      this.updateRecordingState(state);
    });
    
    // Subscribe to messages
    this.conversationManager.messages$.pipe(
      takeUntil(this.destroyed$)
    ).subscribe(messages => {
      this.messages = messages;
      this.shouldScrollToBottom = true;
    });
    
    // Subscribe to transcription
    this.conversationManager.transcription$.pipe(
      takeUntil(this.destroyed$)
    ).subscribe(text => {
      this.currentTranscription = text;
    });
  }

  ngAfterViewChecked(): void {
    if (this.shouldScrollToBottom) {
      this.scrollToBottom();
      this.shouldScrollToBottom = false;
    }
  }

  ngOnDestroy(): void {
    this.destroyed$.next();
    this.destroyed$.complete();
    this.stopVisualization();
    this.cleanupAudio();
    
    if (this.isConversationActive) {
      this.conversationManager.stopConversation();
    }
  }

  async toggleConversation(): Promise<void> {
    if (!this.sessionId) return;
    
    if (this.isConversationActive) {
      this.stopConversation();
    } else {
      await this.startConversation();
    }
  }

  private async startConversation(): Promise<void> {
    try {
      this.loading = true;
      this.error = '';
      
      await this.conversationManager.startConversation(this.sessionId!);
      this.isConversationActive = true;
      this.startVisualization();
      
      this.snackBar.open('Konuşma başlatıldı', 'Close', {
        duration: 2000
      });
    } catch (error: any) {
      console.error('Failed to start conversation:', error);
      this.error = 'Konuşma başlatılamadı. Lütfen tekrar deneyin.';
      this.snackBar.open(this.error, 'Close', {
        duration: 5000,
        panelClass: 'error-snackbar'
      });
    } finally {
      this.loading = false;
    }
  }

  private stopConversation(): void {
    this.conversationManager.stopConversation();
    this.isConversationActive = false;
    this.stopVisualization();
    
    this.snackBar.open('Konuşma sonlandırıldı', 'Close', {
      duration: 2000
    });
  }

  async retryConnection(): Promise<void> {
    this.error = '';
    if (!this.isConversationActive && this.sessionId) {
      await this.startConversation();
    }
  }

  clearChat(): void {
    this.conversationManager.clearMessages();
    this.currentTranscription = '';
    this.error = '';
  }

  performBargeIn(): void {
    this.conversationManager.performBargeIn();
    this.snackBar.open('Kesme yapıldı', 'Close', {
      duration: 1000
    });
  }

  playAudio(audioUrl?: string): void {
    if (!audioUrl) return;
    
    // Stop current audio if playing
    if (this.currentAudio) {
      this.currentAudio.pause();
      this.currentAudio = null;
      this.isPlayingAudio = false;
      return;
    }
    
    this.currentAudio = new Audio(audioUrl);
    this.isPlayingAudio = true;
    
    this.currentAudio.play().catch(error => {
      console.error('Audio playback error:', error);
      this.isPlayingAudio = false;
      this.currentAudio = null;
    });
    
    this.currentAudio.onended = () => {
      this.isPlayingAudio = false;
      this.currentAudio = null;
    };
    
    this.currentAudio.onerror = () => {
      this.isPlayingAudio = false;
      this.currentAudio = null;
      this.snackBar.open('Ses çalınamadı', 'Close', {
        duration: 2000,
        panelClass: 'error-snackbar'
      });
    };
  }

  getStateLabel(state: ConversationState): string {
    const labels: Record<ConversationState, string> = {
      'idle': 'Bekliyor',
      'listening': 'Dinliyor',
      'processing_stt': 'Metin Dönüştürme',
      'processing_llm': 'Yanıt Hazırlanıyor',
      'processing_tts': 'Ses Oluşturuluyor',
      'playing_audio': 'Konuşuyor',
      'error': 'Hata'
    };
    return labels[state] || state;
  }

  closeDialog(): void {
    const result = this.isConversationActive ? 'session_active' : 'closed';
    this.dialogRef.close(result);
  }

  trackByIndex(index: number): number {
    return index;
  }

  private async checkMicrophonePermission(): Promise<void> {
    try {
      const permission = await this.audioService.checkMicrophonePermission();
      if (permission === 'denied') {
        this.error = 'Mikrofon erişimi reddedildi. Lütfen tarayıcı ayarlarından izin verin.';
        this.snackBar.open(this.error, 'Close', {
          duration: 5000,
          panelClass: 'error-snackbar'
        });
      }
    } catch (error) {
      console.error('Failed to check microphone permission:', error);
    }
  }

  private updateRecordingState(state: ConversationState): void {
    this.isRecording = state === 'listening';
  }

  private scrollToBottom(): void {
    try {
      if (this.scrollContainer?.nativeElement) {
        const element = this.scrollContainer.nativeElement;
        element.scrollTop = element.scrollHeight;
      }
    } catch(err) {
      console.error('Scroll error:', err);
    }
  }

  private startVisualization(): void {
    if (!this.audioVisualizer) return;
    
    const canvas = this.audioVisualizer.nativeElement;
    const ctx = canvas.getContext('2d');
    if (!ctx) return;
    
    // Get volume level and visualize
    const draw = async () => {
      if (!this.isConversationActive) {
        this.clearVisualization();
        return;
      }
      
      ctx.fillStyle = '#333';
      ctx.fillRect(0, 0, canvas.width, canvas.height);
      
      if (this.isRecording) {
        // Get actual volume level
        try {
          const volume = await this.audioService.getVolumeLevel();
          
          // Draw volume bars
          ctx.fillStyle = '#4caf50';
          const barCount = 50;
          const barWidth = canvas.width / barCount;
          
          for (let i = 0; i < barCount; i++) {
            const barHeight = Math.random() * volume * canvas.height;
            const x = i * barWidth;
            const y = canvas.height - barHeight;
            
            ctx.fillRect(x, y, barWidth - 2, barHeight);
          }
        } catch (error) {
          // Fallback to random visualization
          ctx.fillStyle = '#4caf50';
          const barCount = 50;
          const barWidth = canvas.width / barCount;
          
          for (let i = 0; i < barCount; i++) {
            const barHeight = Math.random() * canvas.height * 0.8;
            const x = i * barWidth;
            const y = canvas.height - barHeight;
            
            ctx.fillRect(x, y, barWidth - 2, barHeight);
          }
        }
      }
      
      this.animationId = requestAnimationFrame(draw);
    };
    
    draw();
  }

  private stopVisualization(): void {
    if (this.animationId) {
      cancelAnimationFrame(this.animationId);
      this.animationId = null;
    }
    
    this.clearVisualization();
  }

  private clearVisualization(): void {
    if (!this.audioVisualizer) return;
    
    const canvas = this.audioVisualizer.nativeElement;
    const ctx = canvas.getContext('2d');
    if (ctx) {
      ctx.fillStyle = '#333';
      ctx.fillRect(0, 0, canvas.width, canvas.height);
    }
  }

  private cleanupAudio(): void {
    if (this.currentAudio) {
      this.currentAudio.pause();
      this.currentAudio = null;
      this.isPlayingAudio = false;
    }
  }
}