import { Component, OnInit, OnDestroy } from '@angular/core';
import { FormBuilder, FormGroup, Validators, ReactiveFormsModule } from '@angular/forms';
import { FormsModule } from '@angular/forms';
import { MatSnackBar, MatSnackBarModule } from '@angular/material/snack-bar';
import { ApiService } from '../../services/api.service';
import { EnvironmentService } from '../../services/environment.service';
import { CommonModule } from '@angular/common';
import { MatCardModule } from '@angular/material/card';
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatInputModule } from '@angular/material/input';
import { MatSelectModule } from '@angular/material/select';
import { MatButtonModule } from '@angular/material/button';
import { MatIconModule } from '@angular/material/icon';
import { MatSliderModule } from '@angular/material/slider';
import { MatSlideToggleModule } from '@angular/material/slide-toggle';
import { MatExpansionModule } from '@angular/material/expansion';
import { MatDividerModule } from '@angular/material/divider';
import { MatProgressSpinnerModule } from '@angular/material/progress-spinner';
import { MatTooltipModule } from '@angular/material/tooltip';
import { MatDialogModule } from '@angular/material/dialog';
import { Subject, takeUntil } from 'rxjs';

// Provider interfaces
interface ProviderConfig {
  type: string;
  name: string;
  display_name: string;
  requires_endpoint: boolean;
  requires_api_key: boolean;
  requires_repo_info: boolean;
  description?: string;
}

interface ProviderSettings {
  name: string;
  api_key?: string;
  endpoint?: string;
  settings: any;
}

interface EnvironmentConfig {
  llm_provider: ProviderSettings;
  tts_provider: ProviderSettings;
  stt_provider: ProviderSettings;
  providers: ProviderConfig[];
}

@Component({
  selector: 'app-environment',
  standalone: true,
  imports: [
    CommonModule,
    ReactiveFormsModule,
    FormsModule,
    MatCardModule,
    MatFormFieldModule,
    MatInputModule,
    MatSelectModule,
    MatButtonModule,
    MatIconModule,
    MatSliderModule,
    MatSlideToggleModule,
    MatExpansionModule,
    MatDividerModule,
    MatProgressSpinnerModule,
    MatSnackBarModule,
    MatTooltipModule,
    MatDialogModule
  ],
  templateUrl: './environment.component.html',
  styleUrls: ['./environment.component.scss']
})
export class EnvironmentComponent implements OnInit, OnDestroy {
  form: FormGroup;
  loading = false;
  saving = false;
  isLoading = false;
  
  // Provider lists
  llmProviders: ProviderConfig[] = [];
  ttsProviders: ProviderConfig[] = [];
  sttProviders: ProviderConfig[] = [];
  
  // Current provider configurations
  currentLLMProvider?: ProviderConfig;
  currentTTSProvider?: ProviderConfig;
  currentSTTProvider?: ProviderConfig;
  
  // Settings for LLM
  internalPrompt: string = '';
  parameterCollectionConfig: any = {
    enabled: false,
    max_params_per_question: 1,
    show_all_required: false,
    ask_optional_params: false,
    group_related_params: false,
    min_confidence_score: 0.7,
    collection_prompt: 'Please provide the following information:'
  };

  hideSTTKey = true;
  sttLanguages = [
    { code: 'tr-TR', name: 'Türkçe' },
    { code: 'en-US', name: 'English (US)' },
    { code: 'en-GB', name: 'English (UK)' },
    { code: 'de-DE', name: 'Deutsch' },
    { code: 'fr-FR', name: 'Français' },
    { code: 'es-ES', name: 'Español' },
    { code: 'it-IT', name: 'Italiano' },
    { code: 'pt-BR', name: 'Português (BR)' },
    { code: 'ja-JP', name: '日本語' },
    { code: 'ko-KR', name: '한국어' },
    { code: 'zh-CN', name: '中文' }
  ];
  
  sttModels = [
    { value: 'default', name: 'Default' },
    { value: 'latest_short', name: 'Latest Short (Optimized for short audio)' },
    { value: 'latest_long', name: 'Latest Long (Best accuracy)' },
    { value: 'command_and_search', name: 'Command and Search' },
    { value: 'phone_call', name: 'Phone Call (Optimized for telephony)' }
  ];
  
  // API key visibility tracking
  showApiKeys: { [key: string]: boolean } = {};
  
  // Memory leak prevention
  private destroyed$ = new Subject<void>();
  
  constructor(
    private fb: FormBuilder,
    private apiService: ApiService,
    private environmentService: EnvironmentService,
    private snackBar: MatSnackBar
  ) {
    this.form = this.fb.group({
      // LLM Provider
      llm_provider_name: ['', Validators.required],
      llm_provider_api_key: [''],
      llm_provider_endpoint: [''],
      
      // TTS Provider
      tts_provider_name: ['no_tts', Validators.required],
      tts_provider_api_key: [''],
      tts_provider_endpoint: [''],
      
      // STT Provider
      stt_provider_name: ['no_stt', Validators.required],
      stt_provider_api_key: [''],
      stt_provider_endpoint: [''],

      // STT Settings
      stt_settings: this.fb.group({
        language: ['tr-TR'],
        speech_timeout_ms: [2000],
        enable_punctuation: [true],
        interim_results: [true],
        use_enhanced: [true],
        model: ['latest_long'],
        noise_reduction_level: [2],
        vad_sensitivity: [0.5]
      })
    });
  }

  ngOnInit() {
    this.loadEnvironment();
  }

  ngOnDestroy() {
    this.destroyed$.next();
    this.destroyed$.complete();
  }

  // Safe getters for template
  get currentLLMProviderSafe(): ProviderConfig | null {
    return this.currentLLMProvider || null;
  }

  get currentTTSProviderSafe(): ProviderConfig | null {
    return this.currentTTSProvider || null;
  }

  get currentSTTProviderSafe(): ProviderConfig | null {
    return this.currentSTTProvider || null;
  }

  // API key masking methods
  maskApiKey(key?: string): string {
    if (!key) return '';
    if (key.length <= 8) return '••••••••';
    return key.substring(0, 4) + '••••' + key.substring(key.length - 4);
  }

  toggleApiKeyVisibility(fieldName: string): void {
    this.showApiKeys[fieldName] = !this.showApiKeys[fieldName];
  }

  getApiKeyInputType(fieldName: string): string {
    return this.showApiKeys[fieldName] ? 'text' : 'password';
  }

  formatApiKeyForDisplay(fieldName: string, value?: string): string {
    if (this.showApiKeys[fieldName]) {
      return value || '';
    }
    return this.maskApiKey(value);
  }

  loadEnvironment(): void {
    this.loading = true;
    this.isLoading = true;
    
    this.apiService.getEnvironment()
      .pipe(takeUntil(this.destroyed$))
      .subscribe({
        next: (data: any) => {
          // Check if it's new format or legacy
          if (data.llm_provider) {
            this.handleNewFormat(data);
          } else {
            this.handleLegacyFormat(data);
          }
          this.loading = false;
          this.isLoading = false;
        },
        error: (err) => {
          console.error('Failed to load environment:', err);
          this.snackBar.open('Failed to load environment configuration', 'Close', { 
            duration: 3000,
            panelClass: ['error-snackbar']
          });
          this.loading = false;
          this.isLoading = false;
        }
      });
  }

  handleNewFormat(data: EnvironmentConfig): void {
    // Update provider lists
    if (data.providers) {
      this.llmProviders = data.providers.filter(p => p.type === 'llm');
      this.ttsProviders = data.providers.filter(p => p.type === 'tts');
      this.sttProviders = data.providers.filter(p => p.type === 'stt');
    }

    // Set form values
    this.form.patchValue({
      llm_provider_name: data.llm_provider?.name || '',
      llm_provider_api_key: data.llm_provider?.api_key || '',
      llm_provider_endpoint: data.llm_provider?.endpoint || '',
      tts_provider_name: data.tts_provider?.name || 'no_tts',
      tts_provider_api_key: data.tts_provider?.api_key || '',
      tts_provider_endpoint: data.tts_provider?.endpoint || '',
      stt_provider_name: data.stt_provider?.name || 'no_stt',
      stt_provider_api_key: data.stt_provider?.api_key || '',
      stt_provider_endpoint: data.stt_provider?.endpoint || ''
    });

    // Set internal prompt and parameter collection config
    this.internalPrompt = data.llm_provider?.settings?.internal_prompt || '';
    this.parameterCollectionConfig = data.llm_provider?.settings?.parameter_collection_config || this.parameterCollectionConfig;

    // Update current providers
    this.updateCurrentProviders();
    
    // Notify environment service
    if (data.tts_provider?.name !== 'no_tts') {
      this.environmentService.setTTSEnabled(true);
    }
    if (data.stt_provider?.name !== 'no_stt') {
      this.environmentService.setSTTEnabled(true);
    }

    if (data.stt_provider?.settings) {
      this.form.get('stt_settings')?.patchValue(data.stt_provider.settings);
    }    
  }

  handleLegacyFormat(data: any): void {
    console.warn('Legacy environment format detected, using defaults');
    
    // Set default providers if not present
    this.llmProviders = this.getDefaultProviders('llm');
    this.ttsProviders = this.getDefaultProviders('tts');
    this.sttProviders = this.getDefaultProviders('stt');
    
    // Map legacy fields
    this.form.patchValue({
      llm_provider_name: data.work_mode || 'spark',
      llm_provider_api_key: data.cloud_token || '',
      llm_provider_endpoint: data.spark_endpoint || '',
      tts_provider_name: data.tts_engine || 'no_tts',
      tts_provider_api_key: data.tts_engine_api_key || '',
      stt_provider_name: data.stt_engine || 'no_stt',
      stt_provider_api_key: data.stt_engine_api_key || ''
    });
    
    this.internalPrompt = data.internal_prompt || '';
    this.parameterCollectionConfig = data.parameter_collection_config || this.parameterCollectionConfig;
    
    this.updateCurrentProviders();

    if (data.stt_settings) {
      this.form.get('stt_settings')?.patchValue(data.stt_settings);
    }    
  }

  getDefaultProviders(type: string): ProviderConfig[] {
    const defaults: { [key: string]: ProviderConfig[] } = {
      llm: [
        {
          type: 'llm',
          name: 'spark',
          display_name: 'Spark (YTU Cosmos)',
          requires_endpoint: true,
          requires_api_key: true,
          requires_repo_info: true,
          description: 'YTU Cosmos Spark LLM Service'
        },
        {
          type: 'llm',
          name: 'gpt-4o',
          display_name: 'GPT-4o',
          requires_endpoint: false,
          requires_api_key: true,
          requires_repo_info: false,
          description: 'OpenAI GPT-4o model'
        },
        {
          type: 'llm',
          name: 'gpt-4o-mini',
          display_name: 'GPT-4o Mini',
          requires_endpoint: false,
          requires_api_key: true,
          requires_repo_info: false,
          description: 'OpenAI GPT-4o Mini model'
        }
      ],
      tts: [
        {
          type: 'tts',
          name: 'no_tts',
          display_name: 'No TTS',
          requires_endpoint: false,
          requires_api_key: false,
          requires_repo_info: false,
          description: 'Disable text-to-speech'
        },
        {
          type: 'tts',
          name: 'elevenlabs',
          display_name: 'ElevenLabs',
          requires_endpoint: false,
          requires_api_key: true,
          requires_repo_info: false,
          description: 'ElevenLabs TTS service'
        }
      ],
      stt: [
        {
          type: 'stt',
          name: 'no_stt',
          display_name: 'No STT',
          requires_endpoint: false,
          requires_api_key: false,
          requires_repo_info: false,
          description: 'Disable speech-to-text'
        },
        {
          type: 'stt',
          name: 'google',
          display_name: 'Google Cloud Speech',
          requires_endpoint: false,
          requires_api_key: true,
          requires_repo_info: false,
          description: 'Google Cloud Speech-to-Text API'
        },
        {
          type: 'stt',
          name: 'azure',
          display_name: 'Azure Speech Services',
          requires_endpoint: false,
          requires_api_key: true,
          requires_repo_info: false,
          description: 'Azure Cognitive Services Speech'
        },
        {
          type: 'stt',
          name: 'flicker',
          display_name: 'Flicker STT',
          requires_endpoint: true,
          requires_api_key: true,
          requires_repo_info: false,
          description: 'Flicker Speech Recognition Service'
        }
      ]
    };
    
    return defaults[type] || [];
  }

  updateCurrentProviders(): void {
    const llmName = this.form.get('llm_provider_name')?.value;
    const ttsName = this.form.get('tts_provider_name')?.value;
    const sttName = this.form.get('stt_provider_name')?.value;

    this.currentLLMProvider = this.llmProviders.find(p => p.name === llmName);
    this.currentTTSProvider = this.ttsProviders.find(p => p.name === ttsName);
    this.currentSTTProvider = this.sttProviders.find(p => p.name === sttName);

    // Update form validators based on requirements
    this.updateFormValidators();
  }

  updateFormValidators(): void {
    // LLM validators
    if (this.currentLLMProvider?.requires_api_key) {
      this.form.get('llm_provider_api_key')?.setValidators(Validators.required);
    } else {
      this.form.get('llm_provider_api_key')?.clearValidators();
    }
    
    if (this.currentLLMProvider?.requires_endpoint) {
      this.form.get('llm_provider_endpoint')?.setValidators(Validators.required);
    } else {
      this.form.get('llm_provider_endpoint')?.clearValidators();
    }

    // TTS validators
    if (this.currentTTSProvider?.requires_api_key) {
      this.form.get('tts_provider_api_key')?.setValidators(Validators.required);
    } else {
      this.form.get('tts_provider_api_key')?.clearValidators();
    }

    // STT validators
    if (this.currentSTTProvider?.requires_api_key) {
      this.form.get('stt_provider_api_key')?.setValidators(Validators.required);
    } else {
      this.form.get('stt_provider_api_key')?.clearValidators();
    }

    // STT endpoint validator
    if (this.currentSTTProvider?.requires_endpoint) {
      this.form.get('stt_provider_endpoint')?.setValidators(Validators.required);
    } else {
      this.form.get('stt_provider_endpoint')?.clearValidators();
    }
    
    // Update validity
    this.form.get('llm_provider_api_key')?.updateValueAndValidity();
    this.form.get('llm_provider_endpoint')?.updateValueAndValidity();
    this.form.get('tts_provider_api_key')?.updateValueAndValidity();
    this.form.get('stt_provider_api_key')?.updateValueAndValidity();
    this.form.get('stt_provider_endpoint')?.updateValueAndValidity();
  }

  onLLMProviderChange(value: string): void {
    this.currentLLMProvider = this.llmProviders.find(p => p.name === value);
    this.updateFormValidators();
    
    // Reset fields if provider doesn't require them
    if (!this.currentLLMProvider?.requires_api_key) {
      this.form.get('llm_provider_api_key')?.setValue('');
    }
    if (!this.currentLLMProvider?.requires_endpoint) {
      this.form.get('llm_provider_endpoint')?.setValue('');
    }
  }

  onTTSProviderChange(value: string): void {
    this.currentTTSProvider = this.ttsProviders.find(p => p.name === value);
    this.updateFormValidators();
    
    if (!this.currentTTSProvider?.requires_api_key) {
      this.form.get('tts_provider_api_key')?.setValue('');
    }
  
    if (value !== this.form.get('stt_provider_name')?.value) {
      this.form.get('stt_provider_api_key')?.setValue('');
    }
    
    // Provider-specific defaults
    if (value === 'google') {
      this.form.get('stt_settings')?.patchValue({
        model: 'latest_long',
        use_enhanced: true
      });
    } else if (value === 'azure') {
      this.form.get('stt_settings')?.patchValue({
        model: 'default',
        use_enhanced: false
      });
    }
    
    // STT endpoint validator 
    if (this.currentSTTProvider?.requires_endpoint) {
      this.form.get('stt_provider_endpoint')?.setValidators(Validators.required);
    } else {
      this.form.get('stt_provider_endpoint')?.clearValidators();
    }
    
    this.form.get('stt_provider_endpoint')?.updateValueAndValidity();
    
    // Notify environment service
    this.environmentService.setTTSEnabled(value !== 'no_tts');
  }

  onSTTProviderChange(value: string): void {
    this.currentSTTProvider = this.sttProviders.find(p => p.name === value);
    this.updateFormValidators();
    
    if (!this.currentSTTProvider?.requires_api_key) {
      this.form.get('stt_provider_api_key')?.setValue('');
    }
    
    // Notify environment service
    this.environmentService.setSTTEnabled(value !== 'no_stt');
  }

  saveEnvironment(): void {
    if (this.form.invalid || this.saving) {
      this.snackBar.open('Please fix validation errors', 'Close', { 
        duration: 3000,
        panelClass: ['error-snackbar']
      });
      return;
    }

    this.saving = true;
    const formValue = this.form.value;

    const saveData = {
      llm_provider: {
        name: formValue.llm_provider_name,
        api_key: formValue.llm_provider_api_key,
        endpoint: formValue.llm_provider_endpoint,
        settings: {
          internal_prompt: this.internalPrompt,
          parameter_collection_config: this.parameterCollectionConfig
        }
      },
      tts_provider: {
        name: formValue.tts_provider_name,
        api_key: formValue.tts_provider_api_key,
        endpoint: formValue.tts_provider_endpoint,
        settings: {}
      },
      stt_provider: {
        name: formValue.stt_provider_name,
        api_key: formValue.stt_provider_api_key,
        endpoint: formValue.stt_provider_endpoint,
        settings: formValue.stt_settings || {}
      }
    };

    this.apiService.updateEnvironment(saveData as any)
      .pipe(takeUntil(this.destroyed$))
      .subscribe({
        next: () => {
          this.saving = false;
          this.snackBar.open('Environment configuration saved successfully', 'Close', { 
            duration: 3000,
            panelClass: ['success-snackbar']
          });
          
          // Update environment service
          this.environmentService.updateEnvironment(saveData as any);
          
          // Clear form dirty state
          this.form.markAsPristine();
        },
        error: (error) => {
          this.saving = false;
          
          // Race condition handling
          if (error.status === 409) {
            const details = error.error?.details || {};
            this.snackBar.open(
              `Settings were modified by ${details.last_update_user || 'another user'}. Please reload.`,
              'Reload',
              { duration: 0 }
            ).onAction().subscribe(() => {
              this.loadEnvironment();
            });
          } else {
            this.snackBar.open(
              error.error?.detail || 'Failed to save environment configuration',
              'Close',
              { 
                duration: 5000, 
                panelClass: ['error-snackbar'] 
              }
            );
          }
        }
      });
  }

  // Icon helpers
  getLLMProviderIcon(provider: ProviderConfig | null): string {
    if (!provider || !provider.name) return 'smart_toy';
    
    switch(provider.name) {
      case 'gpt-4o':
      case 'gpt-4o-mini':
        return 'psychology';
      case 'spark':
        return 'auto_awesome';
      default:
        return 'smart_toy';
    }
  }

  getTTSProviderIcon(provider: ProviderConfig | null): string {
    if (!provider || !provider.name) return 'record_voice_over';
    
    switch(provider.name) {
      case 'elevenlabs':
        return 'graphic_eq';
      case 'blaze':
        return 'volume_up';
      default:
        return 'record_voice_over';
    }
  }

  getSTTProviderIcon(provider: ProviderConfig | null): string {
    if (!provider || !provider.name) return 'mic';
    
    switch(provider.name) {
      case 'google':
        return 'g_translate';
      case 'azure':
        return 'cloud';
      case 'flicker':
        return 'mic_none';
      default:
        return 'mic';
    }
  }

  getProviderIcon(provider: ProviderConfig): string {
    switch(provider.type) {
      case 'llm':
        return this.getLLMProviderIcon(provider);
      case 'tts':
        return this.getTTSProviderIcon(provider);
      case 'stt':
        return this.getSTTProviderIcon(provider);
      default:
        return 'settings';
    }
  }

  // Helper methods
  getApiKeyLabel(type: string): string {
    switch(type) {
      case 'llm':
        return this.currentLLMProvider?.name === 'spark' ? 'API Token' : 'API Key';
      case 'tts':
        return 'API Key';
      case 'stt':
        return this.currentSTTProvider?.name === 'google' ? 'Credentials JSON Path' : 'API Key';
      default:
        return 'API Key';
    }
  }

  getApiKeyPlaceholder(type: string): string {
    switch(type) {
      case 'llm':
        if (this.currentLLMProvider?.name === 'spark') return 'Enter Spark token';
        if (this.currentLLMProvider?.name?.includes('gpt')) return 'sk-...';
        return 'Enter API key';
      case 'tts':
        return 'Enter TTS API key';
      case 'stt':
        if (this.currentSTTProvider?.name === 'google') return '/path/to/credentials.json';
        if (this.currentSTTProvider?.name === 'azure') return 'subscription_key|region';
        return 'Enter STT API key';
      default:
        return 'Enter API key';
    }
  }

  getEndpointPlaceholder(type: string): string {
    switch(type) {
      case 'llm':
        return 'https://spark-api.example.com';
      case 'tts':
        return 'https://tts-api.example.com';
      case 'stt':
        return 'https://stt-api.example.com';
      default:
        return 'https://api.example.com';
    }
  }

  resetCollectionPrompt(): void {
    this.parameterCollectionConfig.collection_prompt = 'Please provide the following information:';
  }

  testConnection(): void {
    const endpoint = this.form.get('llm_provider_endpoint')?.value;
    if (!endpoint) {
      this.snackBar.open('Please enter an endpoint URL', 'Close', { duration: 2000 });
      return;
    }
    
    this.snackBar.open('Testing connection...', 'Close', { duration: 2000 });
    // TODO: Implement actual connection test
  }
}