/**
 * KnowledgeEntry Domain Entity
 *
 * Represents a single knowledge point stored in Qdrant.
 * Covers all types: PRODUCT (synced), content (DOM), schema (DOM),
 * FAQ/DOCUMENT/CUSTOM (manual).
 *
 * Immutable — all fields readonly. Use static factory fromPayload().
 *
 * @layer Domain
 *
 * (c) 2026 TWWIM UG. All rights reserved. (www.twwim.com)
 */

import { KnowledgeEntryType, KnowledgeSource } from '@archer/domain';

export { KnowledgeEntryType, KnowledgeSource };

export interface KnowledgeEntryProps {
  readonly id: string;
  readonly type: KnowledgeEntryType | string;
  readonly source: KnowledgeSource | string;
  readonly title: string;
  readonly text: string;
  readonly url: string;
  readonly externalId: string;
  readonly sourceId: string;
  readonly category: string;
  readonly categories: readonly string[];
  readonly tags: readonly string[];
  readonly status: string;
  readonly priceMin: number | null;
  readonly priceMax: number | null;
  readonly currency: string;
  readonly variantCount: number;
  readonly imageUrl: string;
  readonly productType: string;
  readonly sectionPath: string;
  readonly chunkCount: number;
}

export class KnowledgeEntry {
  readonly id: string;
  readonly type: KnowledgeEntryType | string;
  readonly source: KnowledgeSource | string;
  readonly title: string;
  readonly text: string;
  readonly url: string;
  readonly externalId: string;
  readonly sourceId: string;
  readonly category: string;
  readonly categories: readonly string[];
  readonly tags: readonly string[];
  readonly status: string;
  readonly priceMin: number | null;
  readonly priceMax: number | null;
  readonly currency: string;
  readonly variantCount: number;
  readonly imageUrl: string;
  readonly productType: string;
  readonly sectionPath: string;
  readonly chunkCount: number;

  private constructor(props: KnowledgeEntryProps) {
    this.id = props.id;
    this.type = props.type;
    this.source = props.source;
    this.title = props.title;
    this.text = props.text;
    this.url = props.url;
    this.externalId = props.externalId;
    this.sourceId = props.sourceId;
    this.category = props.category;
    this.categories = props.categories;
    this.tags = props.tags;
    this.status = props.status;
    this.priceMin = props.priceMin;
    this.priceMax = props.priceMax;
    this.sectionPath = props.sectionPath;
    this.chunkCount = props.chunkCount;
    this.currency = props.currency;
    this.variantCount = props.variantCount;
    this.imageUrl = props.imageUrl;
    this.productType = props.productType;
  }

  get isProduct(): boolean {
    return this.type === KnowledgeEntryType.PRODUCT;
  }

  get isPage(): boolean {
    return this.type === 'content' || this.type === KnowledgeEntryType.PAGE;
  }

  get isManual(): boolean {
    return this.source === KnowledgeSource.MANUAL || this.source === KnowledgeSource.UPLOAD;
  }

  get isSynced(): boolean {
    return this.source === KnowledgeSource.WORDPRESS || this.source === KnowledgeSource.SHOPIFY;
  }

  get priceFormatted(): string {
    if (this.priceMin === null) return '';
    if (this.priceMax === null || this.priceMin === this.priceMax) {
      return `${this.priceMin} ${this.currency}`;
    }
    return `${this.priceMin}–${this.priceMax} ${this.currency}`;
  }

  get preview(): string {
    return this.text.length > 120 ? this.text.slice(0, 120) + '...' : this.text;
  }

  static fromPayload(id: string, payload: Record<string, unknown>): KnowledgeEntry {
    // DOM content uses `text`/`uri`/`section_path`; products use `_text`/`url`
    const text = (payload._text as string) || (payload.text as string) || '';
    const url = (payload.url as string) || (payload.uri as string) || '';
    const sectionPath = (payload.section_path as string) || '';
    const title = (payload.title as string) || sectionPath || url || id;

    return new KnowledgeEntry({
      id,
      type: (payload.type as string) || '',
      source: (payload.source as string) || '',
      title,
      text,
      url,
      externalId: (payload.external_id as string) || '',
      sourceId: (payload.source_id as string) || '',
      category: (payload.category as string) || (payload.categories as string[] | undefined)?.join(', ') || '',
      categories: (payload.categories as string[]) || [],
      tags: (payload.tags as string[]) || [],
      status: (payload.status as string) || '',
      priceMin: (payload.priceMin as number) ?? null,
      priceMax: (payload.priceMax as number) ?? null,
      currency: (payload.currency as string) || '',
      variantCount: (payload.variantCount as number) || 0,
      imageUrl: (payload.imageUrl as string) || '',
      productType: (payload.productType as string) || '',
      sectionPath,
      chunkCount: (payload.chunk_count as number) || 1,
    });
  }
}