import { CommonModule } from '@angular/common';
import { Component, inject, OnDestroy, OnInit, signal } from '@angular/core';
import { FormBuilder, FormGroup, ReactiveFormsModule, Validators } from '@angular/forms';
import { MatButtonModule } from '@angular/material/button';
import { MatCardModule } from '@angular/material/card';
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatIconModule } from '@angular/material/icon';
import { MatInputModule } from '@angular/material/input';
import { MatProgressSpinnerModule } from '@angular/material/progress-spinner';
import { MatSnackBar, MatSnackBarModule } from '@angular/material/snack-bar';
import { MatTableModule } from '@angular/material/table';
import { interval, Subscription } from 'rxjs';
import { ApiService, RiskEvaluation, RiskThresholds } from '../../services/api.service';

@Component({
  selector: 'app-risk-management',
  standalone: true,
  imports: [
    CommonModule,
    MatCardModule,
    MatIconModule,
    MatButtonModule,
    MatTableModule,
    MatFormFieldModule,
    MatInputModule,
    MatSnackBarModule,
    MatProgressSpinnerModule,
    ReactiveFormsModule,
  ],
  templateUrl: './risk-management.component.html',
  styleUrl: './risk-management.component.css',
})
export class RiskManagementComponent implements OnInit, OnDestroy {
  private apiService = inject(ApiService);
  private snackBar = inject(MatSnackBar);
  private fb = inject(FormBuilder);
  private subscriptions: Subscription[] = [];

  protected riskThresholds = signal<RiskThresholds | null>(null);
  protected riskHistory = signal<RiskEvaluation[]>([]);
  protected isLoading = signal<boolean>(true);
  protected isSaving = signal<boolean>(false);
  protected error = signal<string | null>(null);

  protected thresholdsForm: FormGroup;
  protected displayedColumns = ['symbol', 'positionValue', 'riskLevel', 'violations', 'timestamp'];

  constructor() {
    this.thresholdsForm = this.fb.group({
      maxPositionSize: [0, [Validators.required, Validators.min(0)]],
      maxDailyLoss: [0, [Validators.required, Validators.min(0)]],
      maxPortfolioRisk: [0, [Validators.required, Validators.min(0), Validators.max(1)]],
      volatilityLimit: [0, [Validators.required, Validators.min(0), Validators.max(1)]],
    });
  }

  ngOnInit() {
    this.loadRiskThresholds();
    this.loadRiskHistory();

    // Refresh risk history every 30 seconds
    const historySubscription = interval(30000).subscribe(() => {
      this.loadRiskHistory();
    });
    this.subscriptions.push(historySubscription);
  }

  ngOnDestroy() {
    this.subscriptions.forEach(sub => sub.unsubscribe());
  }

  private loadRiskThresholds() {
    this.apiService.getRiskThresholds().subscribe({
      next: response => {
        this.riskThresholds.set(response.data);
        this.thresholdsForm.patchValue(response.data);
        this.isLoading.set(false);
        this.error.set(null);
      },
      error: err => {
        console.error('Failed to load risk thresholds:', err);
        this.error.set('Failed to load risk thresholds');
        this.isLoading.set(false);
        this.snackBar.open('Failed to load risk thresholds', 'Dismiss', { duration: 5000 });
      },
    });
  }

  private loadRiskHistory() {
    this.apiService.getRiskHistory().subscribe({
      next: response => {
        this.riskHistory.set(response.data);
      },
      error: err => {
        console.error('Failed to load risk history:', err);
        this.snackBar.open('Failed to load risk history', 'Dismiss', { duration: 3000 });
      },
    });
  }

  saveThresholds() {
    if (this.thresholdsForm.valid) {
      this.isSaving.set(true);
      const thresholds = this.thresholdsForm.value as RiskThresholds;

      this.apiService.updateRiskThresholds(thresholds).subscribe({
        next: response => {
          this.riskThresholds.set(response.data);
          this.isSaving.set(false);
          this.snackBar.open('Risk thresholds updated successfully', 'Dismiss', { duration: 3000 });
        },
        error: err => {
          console.error('Failed to save risk thresholds:', err);
          this.isSaving.set(false);
          this.snackBar.open('Failed to save risk thresholds', 'Dismiss', { duration: 5000 });
        },
      });
    }
  }

  refreshData() {
    this.isLoading.set(true);
    this.loadRiskThresholds();
    this.loadRiskHistory();
  }

  getRiskLevelColor(level: string): string {
    switch (level) {
      case 'LOW':
        return 'text-green-600';
      case 'MEDIUM':
        return 'text-yellow-600';
      case 'HIGH':
        return 'text-red-600';
      default:
        return 'text-gray-600';
    }
  }
}