import { Injectable } from '@angular/core';
import { DouyinTranscriptJob, DouyinTranscriptStatus } from '../models/douyin-insight.model';

@Injectable({ providedIn: 'root' })
export class ViralTranscriptPresenterService {
  private readonly processingStatuses = new Set<DouyinTranscriptStatus>([
    'queued',
    'resolving_detail',
    'selecting_media',
    'downloading_media',
    'extracting_audio',
    'submitting_provider',
    'polling_provider',
    'pending',
  ]);

  private readonly labels: Record<DouyinTranscriptStatus, string> = {
    queued: '排队中',
    resolving_detail: '获取视频详情',
    selecting_media: '选择媒体',
    downloading_media: '下载媒体',
    extracting_audio: '提取音频',
    submitting_provider: '提交转写',
    polling_provider: '等待结果',
    pending: '处理中',
    completed: '已完成',
    failed: '失败',
    needs_media: '缺少可转写媒体',
    needs_media_processing: '需要媒体处理环境',
    needs_provider_config: '服务未配置',
  };

  canStart(analysis: { transcript?: string; transcriptJob?: DouyinTranscriptJob } | null | undefined, busy: boolean): boolean {
    if (!analysis || busy || !!analysis.transcript) return false;
    const status = analysis.transcriptJob?.status;
    return !status
      || status === 'failed'
      || status === 'needs_media'
      || status === 'needs_media_processing'
      || status === 'needs_provider_config';
  }

  statusLabel(job: DouyinTranscriptJob | undefined): string {
    if (!job) return '未提交';
    return this.labels[job.status] || job.stageLabel || '未知状态';
  }

  primaryMessage(job: DouyinTranscriptJob | undefined): string {
    if (!job) return '';
    return this.message(job);
  }

  isProcessing(job: DouyinTranscriptJob | undefined): boolean {
    return !!job && this.processingStatuses.has(job.status);
  }

  shouldWarn(job: DouyinTranscriptJob | undefined): boolean {
    return !!job && job.status !== 'completed' && !this.isProcessing(job);
  }

  toastType(job: DouyinTranscriptJob): 'success' | 'warn' {
    return this.isProcessing(job) || job.status === 'completed' ? 'success' : 'warn';
  }

  message(job: DouyinTranscriptJob): string {
    if (job.stageLabel && this.isProcessing(job)) return job.stageLabel;
    if (job.status === 'pending' || job.status === 'queued') return '逐字稿任务已提交，稍后可刷新结果';
    if (job.status === 'completed') return '逐字稿已回填';
    if (job.status === 'needs_media') return '未找到可转写媒体，请确认视频详情能返回音频或视频地址';
    if (job.status === 'needs_media_processing') return job.errorMessage || '需要可用的媒体处理环境，请确认本地 ffmpeg 可用';
    if (job.status === 'needs_provider_config') {
      return job.warnings?.[0] || '未读取到转写服务配置，请检查 VOC_TOKEN、TRANSCRIPTION_VOC_TOKEN 或 VOICE_TOKEN';
    }
    return job.errorMessage || job.warnings?.[0] || '逐字稿任务失败，可修复配置后重新提交';
  }
}