/**
 * Data Transformers
 * Story 1.3: Content Migration Script
 *
 * Transforms Webflow data to Payload CMS format
 */

import type {
  PayloadCategory,
  PayloadPostData,
  PayloadPortfolioData,
  WebflowCategory,
  WebflowPost,
  WebflowPortfolioItem,
} from './types'
import { toSlug, splitColorToTextBackground, truncate, htmlToPlainText, parseDate } from './utils'
import { htmlToLexical } from './lexicalConverter'

// ============================================================
// CATEGORY TRANSFORMER
// ============================================================

/**
 * Transform Webflow category to Payload CMS format
 */
export function transformCategory(
  webflowCategory: WebflowCategory,
  order: number = 0,
): PayloadCategory {
  const { textColor, backgroundColor } = splitColorToTextBackground(
    webflowCategory.colorHex || '#ffffff',
  )

  return {
    title: webflowCategory.name,
    nameEn: '', // Can be manually set later
    order,
    textColor,
    backgroundColor,
    slug: webflowCategory.slug || toSlug(webflowCategory.name),
  }
}

/**
 * Transform multiple categories
 */
export function transformCategories(
  webflowCategories: WebflowCategory[],
): PayloadCategory[] {
  return webflowCategories.map((cat, index) => transformCategory(cat, index))
}

// ============================================================
// POST TRANSFORMER
// ============================================================

/**
 * Transform Webflow post to Payload CMS format
 */
export function transformPost(webflowPost: WebflowPost): PayloadPostData {
  // Generate excerpt from content if not provided
  const excerpt = webflowPost.excerpt || htmlToPlainText(webflowPost.content, 200)

  // Convert HTML to Lexical JSON string format (for richText field storage)
  const lexicalContent = htmlToLexical(webflowPost.content || '')

  return {
    title: webflowPost.title,
    slug: webflowPost.slug || toSlug(webflowPost.title),
    heroImage: undefined, // Will be set by media handler
    ogImage: undefined, // Will be set by media handler
    content: lexicalContent as any, // Lexical JSON string for richText field
    excerpt: truncate(excerpt, 200),
    publishedAt: parseDate(webflowPost.publishedDate),
    status: 'published',
    categories: [], // Will be resolved after categories are migrated
    meta: {
      title: webflowPost.seoTitle || webflowPost.title,
      description: webflowPost.seoDescription || excerpt,
      image: undefined, // Will be set by media handler
    },
  }
}

/**
 * Transform multiple posts
 */
export function transformPosts(webflowPosts: WebflowPost[]): PayloadPostData[] {
  return webflowPosts.map((post) => transformPost(post))
}

// ============================================================
// PORTFOLIO TRANSFORMER
// ============================================================

/**
 * Transform Webflow portfolio item to Payload CMS format
 */
export function transformPortfolio(
  webflowPortfolio: WebflowPortfolioItem,
): PayloadPortfolioData {
  return {
    title: webflowPortfolio.name,
    slug: webflowPortfolio.slug || toSlug(webflowPortfolio.name),
    url: webflowPortfolio.websiteLink,
    image: undefined, // Will be set by media handler
    description: webflowPortfolio.description,
    websiteType: webflowPortfolio.websiteType || 'other',
    tags: parseTagsString(webflowPortfolio.tags),
  }
}

/**
 * Transform multiple portfolio items
 */
export function transformPortfolios(
  webflowPortfolios: WebflowPortfolioItem[],
): PayloadPortfolioData[] {
  return webflowPortfolios.map((item) => transformPortfolio(item))
}

// ============================================================
// HELPER FUNCTIONS
// ============================================================

/**
 * Parse comma-separated tags into array
 */
function parseTagsString(tagsString: string): Array<{ tag: string }> {
  if (!tagsString || typeof tagsString !== 'string') {
    return []
  }
  return tagsString
    .split(',')
    .map((tag) => tag.trim())
    .filter(Boolean)
    .map((tag) => ({ tag }))
}

// ============================================================
// VALIDATION FUNCTIONS
// ============================================================

/**
 * Validate transformed category
 */
export function validateCategory(category: PayloadCategory): { valid: boolean; errors: string[] } {
  const errors: string[] = []

  if (!category.title) {
    errors.push('Category title is required')
  }
  if (!category.slug) {
    errors.push('Category slug is required')
  }
  if (!category.textColor || !category.backgroundColor) {
    errors.push('Category colors are required')
  }

  return { valid: errors.length === 0, errors }
}

/**
 * Validate transformed post
 */
export function validatePost(post: PayloadPostData): { valid: boolean; errors: string[] } {
  const errors: string[] = []

  if (!post.title) {
    errors.push('Post title is required')
  }
  if (!post.slug) {
    errors.push('Post slug is required')
  }
  if (!post.content) {
    errors.push('Post content is required')
  }
  if (!post.publishedAt) {
    errors.push('Post published date is required')
  }

  return { valid: errors.length === 0, errors }
}

/**
 * Validate transformed portfolio item
 */
export function validatePortfolio(
  portfolio: PayloadPortfolioData,
): { valid: boolean; errors: string[] } {
  const errors: string[] = []

  if (!portfolio.title) {
    errors.push('Portfolio title is required')
  }
  if (!portfolio.slug) {
    errors.push('Portfolio slug is required')
  }
  if (!portfolio.url) {
    errors.push('Portfolio URL is required')
  }
  if (!portfolio.websiteType) {
    errors.push('Portfolio website type is required')
  }

  return { valid: errors.length === 0, errors }
}