import { Injectable } from '@angular/core';
import { AuthCreditService } from './auth-credit.service';
import { GenerationTemplate, GenerationTemplateInput } from '../models/template.model';
import { PipelineRoute } from '../pipelines/pipeline-registry';

const STORAGE_KEY = 'videoWorkflow.templates.user.v1';

@Injectable({ providedIn: 'root' })
export class TemplateService {
  private readonly systemTemplates: GenerationTemplate[] = this.buildSystemTemplates();

  constructor(private auth: AuthCreditService) {}

  listTemplates(): GenerationTemplate[] {
    const userId = this.auth.currentUser?.objectId || '';
    const userTemplates = this.readUserTemplates().filter((item) => item.userId === userId);
    return [...this.systemTemplates, ...userTemplates].sort((a, b) => {
      if (a.scope !== b.scope) return a.scope === 'system' ? -1 : 1;
      return Date.parse(b.updatedAt) - Date.parse(a.updatedAt);
    });
  }

  listByPipeline(pipelineId: PipelineRoute): GenerationTemplate[] {
    return this.listTemplates().filter((item) => item.pipelineId === pipelineId);
  }

  createUserTemplate(input: GenerationTemplateInput): GenerationTemplate {
    const userId = this.requireUserId();
    const now = new Date().toISOString();
    const template: GenerationTemplate = {
      ...input,
      id: input.id || this.createId(),
      userId,
      scope: 'user',
      tags: this.uniqueTags(input.tags || []),
      config: this.cloneSerializable(input.config || {}),
      version: input.version || 1,
      usageCount: 0,
      createdAt: now,
      updatedAt: now,
    };
    const items = this.readUserTemplates();
    items.unshift(template);
    this.writeUserTemplates(items);
    return template;
  }

  cloneToUser(templateId: string): GenerationTemplate {
    const source = this.listTemplates().find((item) => item.id === templateId);
    if (!source) throw new Error('未找到模板');
    return this.createUserTemplate({
      pipelineId: source.pipelineId,
      name: `${source.name} 副本`,
      description: source.description || '',
      category: source.category,
      tags: source.tags || [],
      config: this.cloneSerializable(source.config || {}),
      preview: source.preview,
      version: source.version,
    });
  }

  updateUserTemplate(id: string, patch: Partial<GenerationTemplateInput>): GenerationTemplate {
    const userId = this.requireUserId();
    const items = this.readUserTemplates();
    const index = items.findIndex((item) => item.id === id && item.userId === userId);
    if (index < 0) throw new Error('未找到可编辑的模板');
    const updated: GenerationTemplate = {
      ...items[index],
      ...patch,
      id: items[index].id,
      userId,
      scope: 'user',
      tags: patch.tags ? this.uniqueTags(patch.tags) : items[index].tags,
      config: patch.config ? this.cloneSerializable(patch.config) : items[index].config,
      updatedAt: new Date().toISOString(),
    };
    items[index] = updated;
    this.writeUserTemplates(items);
    return updated;
  }

  deleteUserTemplate(id: string): void {
    const userId = this.requireUserId();
    this.writeUserTemplates(this.readUserTemplates().filter((item) => !(item.id === id && item.userId === userId)));
  }

  markUsed(id: string): void {
    const userId = this.auth.currentUser?.objectId || '';
    const items = this.readUserTemplates();
    const index = items.findIndex((item) => item.id === id && item.userId === userId);
    if (index < 0) return;
    items[index] = {
      ...items[index],
      usageCount: Number(items[index].usageCount || 0) + 1,
      updatedAt: new Date().toISOString(),
    };
    this.writeUserTemplates(items);
  }

  private requireUserId(): string {
    const userId = this.auth.currentUser?.objectId;
    if (!userId) {
      this.auth.requestLogin('模板库');
      throw new Error('请先登录后保存模板');
    }
    return userId;
  }

  private readUserTemplates(): GenerationTemplate[] {
    try {
      const raw = localStorage.getItem(STORAGE_KEY);
      const parsed = raw ? JSON.parse(raw) : [];
      return Array.isArray(parsed) ? parsed : [];
    } catch {
      return [];
    }
  }

  private writeUserTemplates(items: GenerationTemplate[]): void {
    localStorage.setItem(STORAGE_KEY, JSON.stringify(items));
  }

  private createId(): string {
    return `tpl_${Date.now()}_${Math.random().toString(36).slice(2, 8)}`;
  }

  private uniqueTags(tags: string[]): string[] {
    return tags.map((item) => String(item || '').trim()).filter((item, index, list) => !!item && list.indexOf(item) === index).slice(0, 12);
  }

  private cloneSerializable<T>(value: T): T {
    return JSON.parse(JSON.stringify(value || {}));
  }

  private buildSystemTemplates(): GenerationTemplate[] {
    const now = '2026-06-01T00:00:00.000Z';
    return [
      {
        id: 'sys_topic_knowledge_short',
        scope: 'system',
        pipelineId: 'topic-to-video',
        name: '知识口播短平快',
        description: '适合把一个观点拆成 3-5 个短分镜，节奏清晰，适合日更知识内容。',
        category: '知识科普',
        tags: ['口播', '知识', '日更'],
        config: {
          nScenes: 4,
          aspect: 'portrait',
          quickMode: true,
          mediaMode: 'image',
          clipFrames: 121,
          clipQuality: '720p',
          continuityEnabled: true,
          visualBible: {
            subject: '自信讲述者或干净的知识符号主体',
            product: '',
            location: '极简演播室或清爽信息图背景',
            palette: '白色、蓝色、高对比强调色',
            lighting: '柔和棚拍光',
            camera: '中近景，构图干净',
            styleNotes: '轻量信息图风格，大号关键词，层级清晰',
            constraints: '保持统一配色和讲述者风格',
          },
          scriptFrame: '开头提出反常识观点 -> 三点解释 -> 结尾抛出行动建议',
        },
        version: 1,
        usageCount: 0,
        createdAt: now,
        updatedAt: now,
      },
      {
        id: 'sys_topic_product_seed',
        scope: 'system',
        pipelineId: 'topic-to-video',
        name: '产品种草结构',
        description: '从用户痛点切入，突出使用场景、差异点和购买理由。',
        category: '产品种草',
        tags: ['种草', '产品', '转化'],
        config: {
          nScenes: 5,
          aspect: 'portrait',
          quickMode: true,
          mediaMode: 'video',
          clipFrames: 121,
          clipQuality: '720p',
          continuityEnabled: true,
          visualBible: {
            subject: '日常使用场景中的目标用户',
            product: '细节清晰的主推产品',
            location: '明亮的生活方式场景',
            palette: '温暖中性色，搭配清新的强调色',
            lighting: '自然日光',
            camera: '产品细节特写与平滑运镜',
            styleNotes: '真实产品广告质感，构图干净',
            constraints: '保持产品颜色和形状一致',
          },
          scriptFrame: '痛点场景 -> 产品出现 -> 三个卖点 -> 使用前后对比 -> 轻 CTA',
        },
        version: 1,
        usageCount: 0,
        createdAt: now,
        updatedAt: now,
      },
      {
        id: 'sys_image_cover_clean',
        scope: 'system',
        pipelineId: 'image-generation',
        name: '清爽封面图',
        description: '适合生成视频封面、知识卡片和素材库配图。',
        category: '其他',
        tags: ['封面', '信息图', '浅色'],
        config: {
          width: 1440,
          height: 1920,
          stylePrompt: '清爽浅色背景，主体明确，大标题留白，少量高对比强调色',
        },
        version: 1,
        usageCount: 0,
        createdAt: now,
        updatedAt: now,
      },
      {
        id: 'sys_dh_explainer',
        scope: 'system',
        pipelineId: 'digital-human',
        name: '数字人讲解',
        description: '适合课程介绍、产品说明、短口播讲解。',
        category: '口播',
        tags: ['数字人', '讲解', '口播'],
        config: {
          resolution: '1080p',
          scriptFrame: '问候 -> 背景问题 -> 核心说明 -> 适用人群 -> 行动建议',
          voiceMood: '自然、清晰、可信',
        },
        version: 1,
        usageCount: 0,
        createdAt: now,
        updatedAt: now,
      },
    ];
  }
}