import type { ViewDataBuilder } from '@/lib/contracts/builders/ViewDataBuilder';
import { HealthAlertFormatter } from '@/lib/formatters/HealthAlertFormatter';
import { HealthComponentFormatter } from '@/lib/formatters/HealthComponentFormatter';
import { HealthMetricFormatter } from '@/lib/formatters/HealthMetricFormatter';
import { HealthStatusFormatter } from '@/lib/formatters/HealthStatusFormatter';
import type { HealthDTO } from '../../../../api/src/domain/health/HealthDTO';
import type { HealthAlert, HealthComponent, HealthMetrics, HealthStatus, HealthViewData } from '@/lib/view-data/HealthViewData';

export type { HealthDTO };

export class HealthViewDataBuilder {
  public static build(apiDto: HealthDTO): HealthViewData {
    const now = new Date();
    const lastUpdated = apiDto.timestamp || now.toISOString();

    // Build overall status
    const overallStatus: HealthStatus = {
      status: apiDto.status,
      timestamp: apiDto.timestamp,
      formattedTimestamp: HealthStatusFormatter.formatTimestamp(apiDto.timestamp),
      relativeTime: HealthStatusFormatter.formatRelativeTime(apiDto.timestamp),
      statusLabel: HealthStatusFormatter.formatStatusLabel(apiDto.status),
      statusColor: HealthStatusFormatter.formatStatusColor(apiDto.status),
      statusIcon: HealthStatusFormatter.formatStatusIcon(apiDto.status),
    };

    // Build metrics
    const metrics: HealthMetrics = {
      uptime: HealthMetricFormatter.formatUptime(apiDto.uptime),
      responseTime: HealthMetricFormatter.formatResponseTime(apiDto.responseTime),
      errorRate: HealthMetricFormatter.formatErrorRate(apiDto.errorRate),
      lastCheck: apiDto.lastCheck || lastUpdated,
      formattedLastCheck: HealthMetricFormatter.formatTimestamp(apiDto.lastCheck || lastUpdated),
      checksPassed: apiDto.checksPassed || 0,
      checksFailed: apiDto.checksFailed || 0,
      totalChecks: (apiDto.checksPassed || 0) + (apiDto.checksFailed || 0),
      successRate: HealthMetricFormatter.formatSuccessRate(apiDto.checksPassed, apiDto.checksFailed),
    };

    // Build components
    const components: HealthComponent[] = (apiDto.components || []).map((component: { name: string; status: 'ok' | 'degraded' | 'error' | 'unknown'; lastCheck?: string; responseTime?: number; errorRate?: number; }) => ({
      name: component.name,
      status: component.status,
      statusLabel: HealthComponentFormatter.formatStatusLabel(component.status),
      statusColor: HealthComponentFormatter.formatStatusColor(component.status),
      statusIcon: HealthComponentFormatter.formatStatusIcon(component.status),
      lastCheck: component.lastCheck || lastUpdated,
      formattedLastCheck: HealthComponentFormatter.formatTimestamp(component.lastCheck || lastUpdated),
      responseTime: HealthMetricFormatter.formatResponseTime(component.responseTime),
      errorRate: HealthMetricFormatter.formatErrorRate(component.errorRate),
    }));

    // Build alerts
    const alerts: HealthAlert[] = (apiDto.alerts || []).map((alert: { id: string; type: 'critical' | 'warning' | 'info'; title: string; message: string; timestamp: string; }) => ({
      id: alert.id,
      type: alert.type,
      title: alert.title,
      message: alert.message,
      timestamp: alert.timestamp,
      formattedTimestamp: HealthAlertFormatter.formatTimestamp(alert.timestamp),
      relativeTime: HealthAlertFormatter.formatRelativeTime(alert.timestamp),
      severity: HealthAlertFormatter.formatSeverity(alert.type),
      severityColor: HealthAlertFormatter.formatSeverityColor(alert.type),
    }));

    // Calculate derived fields
    const hasAlerts = alerts.length > 0;
    const hasDegradedComponents = components.some((c) => c.status === 'degraded');
    const hasErrorComponents = components.some((c) => c.status === 'error');

    return {
      overallStatus,
      metrics,
      components,
      alerts,
      hasAlerts,
      hasDegradedComponents,
      hasErrorComponents,
      lastUpdated,
      formattedLastUpdated: HealthStatusFormatter.formatTimestamp(lastUpdated),
    };
  }
}

HealthViewDataBuilder satisfies ViewDataBuilder<HealthDTO, HealthViewData>;