#!/usr/bin/env tsx
/**
 * extract-types.ts
 *
 * Copies payload-types.ts from the CMS repo into the contracts package
 * and generates curated re-export modules for frontend consumption.
 *
 * Usage: tsx scripts/extract-types.ts [path-to-payload-types.ts]
 * Default: ../payload-cms/src/payload-types.ts
 */

import { readFileSync, writeFileSync, mkdirSync } from 'node:fs'
import { resolve, dirname } from 'node:path'
import { fileURLToPath } from 'node:url'

const __dirname = dirname(fileURLToPath(import.meta.url))
const ROOT = resolve(__dirname, '..')
const TYPES_DIR = resolve(ROOT, 'src/types')

const sourcePath = process.argv[2] || resolve(ROOT, '../payload-cms/src/payload-types.ts')

console.log(`[extract] Reading types from: ${sourcePath}`)
const source = readFileSync(sourcePath, 'utf-8')

// Ensure output directory exists
mkdirSync(TYPES_DIR, { recursive: true })

// 1. Copy full payload-types.ts
const header = `/* Auto-extracted from Payload CMS — DO NOT EDIT MANUALLY */
/* Re-run: pnpm extract */
/* Source: payload-cms/src/payload-types.ts */\n\n`

// Strip the `declare module 'payload'` augmentation — frontends don't have payload installed
const cleanedSource = source.replace(/\s*declare module 'payload' \{[\s\S]*?\}\s*$/, '\n')
writeFileSync(resolve(TYPES_DIR, 'payload-types.ts'), header + cleanedSource)
console.log('[extract] Copied payload-types.ts')

// 2. Extract interface names from the Config.collections mapping
const collectionsMatch = source.match(/collections:\s*\{([^}]+)\}/s)
if (!collectionsMatch) {
  console.error('[extract] Could not find collections in Config interface')
  process.exit(1)
}

// Parse lines like "    users: User;" or "    'social-links': SocialLink;"
const collectionEntries = [...collectionsMatch[1].matchAll(/^\s*'?([a-z][\w-]*)'?\s*:\s*(\w+)\s*;/gm)]
  .map(m => ({ slug: m[1], typeName: m[2] }))

console.log(`[extract] Found ${collectionEntries.length} collections`)

// Define which collections are frontend-relevant (exclude system/admin-only)
const SYSTEM_COLLECTIONS = new Set([
  'payload-kv', 'payload-locked-documents', 'payload-preferences', 'payload-migrations',
  'email-logs', 'audit-logs', 'consent-logs', 'form-submissions', 'redirects',
  'social-accounts', 'social-platforms', 'community-interactions', 'community-templates',
  'community-rules', 'report-schedules', 'youtube-channels', 'youtube-content',
  'yt-tasks', 'yt-notifications', 'yt-batches', 'yt-monthly-goals',
  'yt-script-templates', 'yt-checklist-templates', 'yt-series',
])

const frontendCollections = collectionEntries.filter(c => !SYSTEM_COLLECTIONS.has(c.slug))
const systemCollections = collectionEntries.filter(c => SYSTEM_COLLECTIONS.has(c.slug))

console.log(`[extract] Frontend collections: ${frontendCollections.length}`)
console.log(`[extract] System collections (excluded): ${systemCollections.length}`)

// 3. Generate collections.ts — re-exports of frontend-relevant collection types
const collectionsFile = `/**
 * Frontend-relevant collection types
 * Auto-generated by extract-types.ts — DO NOT EDIT MANUALLY
 */
import type {
${frontendCollections.map(c => `  ${c.typeName},`).join('\n')}
} from './payload-types'

// Re-export all types
export type {
${frontendCollections.map(c => `  ${c.typeName},`).join('\n')}
} from './payload-types'

/**
 * Collection slug to type mapping for frontend use
 */
export interface CollectionTypeMap {
${frontendCollections.map(c => `  '${c.slug}': ${c.typeName};`).join('\n')}
}

export type CollectionSlug = keyof CollectionTypeMap
`

writeFileSync(resolve(TYPES_DIR, 'collections.ts'), collectionsFile)
console.log('[extract] Generated collections.ts')

// 4. Extract block types from the Page interface
// Blocks are defined as a union within the Page.layout array
const blockTypes: string[] = []
const blockTypeRegex = /blockType:\s*'([^']+)'/g
let match: RegExpExecArray | null

// Only scan the Page interface section (roughly lines 519-3070)
const pageSection = source.substring(
  source.indexOf('export interface Page'),
  source.indexOf('export interface Video')
)

while ((match = blockTypeRegex.exec(pageSection)) !== null) {
  if (!blockTypes.includes(match[1])) {
    blockTypes.push(match[1])
  }
}

console.log(`[extract] Found ${blockTypes.length} block types`)

// 5. Generate blocks.ts
const blocksFile = `/**
 * Block type definitions
 * Auto-generated by extract-types.ts — DO NOT EDIT MANUALLY
 */
export type { Page } from './payload-types'

/**
 * Union of all page block types (extracted from Page.layout)
 * Each block has a discriminant 'blockType' field.
 *
 * Usage:
 *   import type { Block } from '@c2s/payload-contracts/types'
 *   if (block.blockType === 'hero-block') { ... }
 */
import type { Page } from './payload-types'

export type Block = NonNullable<Page['layout']>[number]

/**
 * Extract a specific block type by its blockType discriminant
 *
 * Usage:
 *   type HeroBlock = BlockByType<'hero-block'>
 */
export type BlockByType<T extends Block['blockType']> = Extract<Block, { blockType: T }>

/**
 * All block type slugs as a const array
 */
export const BLOCK_TYPES = [
${blockTypes.map(b => `  '${b}',`).join('\n')}
] as const

export type BlockType = typeof BLOCK_TYPES[number]
`

writeFileSync(resolve(TYPES_DIR, 'blocks.ts'), blocksFile)
console.log('[extract] Generated blocks.ts')

// 6. Generate media.ts — dedicated Media type with image sizes documentation
const mediaFile = `/**
 * Media type with responsive image sizes
 * Auto-generated by extract-types.ts — DO NOT EDIT MANUALLY
 */
export type { Media } from './payload-types'

import type { Media } from './payload-types'

/**
 * All available image size names
 *
 * Standard sizes: thumbnail, small, medium, large, xlarge, 2k, og
 * AVIF sizes: medium_avif, large_avif, xlarge_avif
 */
export type ImageSizeName = keyof NonNullable<Media['sizes']>

/**
 * A single image size entry
 */
export type ImageSize = NonNullable<NonNullable<Media['sizes']>[ImageSizeName]>

/**
 * Helper to get the URL of a specific size, with fallback
 */
export function getImageUrl(media: Media | null | undefined, size: ImageSizeName = 'large'): string | null {
  if (!media) return null
  const sizeData = media.sizes?.[size]
  return sizeData?.url || media.url || null
}

/**
 * Get srcSet string for responsive images
 */
export function getSrcSet(media: Media | null | undefined, sizes: ImageSizeName[] = ['small', 'medium', 'large', 'xlarge']): string {
  if (!media?.sizes) return ''
  return sizes
    .map(size => {
      const s = media.sizes?.[size]
      if (!s?.url || !s?.width) return null
      return \`\${s.url} \${s.width}w\`
    })
    .filter(Boolean)
    .join(', ')
}
`

writeFileSync(resolve(TYPES_DIR, 'media.ts'), mediaFile)
console.log('[extract] Generated media.ts')

// 7. Generate api.ts — API response types that Payload returns
const apiFile = `/**
 * Payload CMS REST API response types
 * These match the actual JSON responses from the Payload REST API.
 */

/**
 * Paginated collection response
 * Returned by: GET /api/{collection}
 */
export interface PaginatedResponse<T> {
  docs: T[]
  totalDocs: number
  limit: number
  totalPages: number
  page: number
  pagingCounter: number
  hasPrevPage: boolean
  hasNextPage: boolean
  prevPage: number | null
  nextPage: number | null
}

/**
 * Single document response
 * Returned by: GET /api/{collection}/{id}
 */
export type SingleResponse<T> = T

/**
 * Error response from Payload API
 */
export interface PayloadError {
  errors: Array<{
    message: string
    name?: string
    data?: Record<string, unknown>
  }>
}

/**
 * Query parameters for collection requests
 */
export interface CollectionQueryParams {
  /** Depth of relationship population (0-10) */
  depth?: number
  /** Locale for localized fields */
  locale?: 'de' | 'en'
  /** Fallback locale when field is empty */
  fallbackLocale?: 'de' | 'en' | 'none'
  /** Number of results per page */
  limit?: number
  /** Page number */
  page?: number
  /** Sort field (prefix with - for descending) */
  sort?: string
  /** Payload query filter (where clause) */
  where?: Record<string, unknown>
  /** Draft mode */
  draft?: boolean
}

/**
 * Query parameters for global requests
 */
export interface GlobalQueryParams {
  depth?: number
  locale?: 'de' | 'en'
  fallbackLocale?: 'de' | 'en' | 'none'
  draft?: boolean
}

/**
 * Available locales in this Payload instance
 */
export type Locale = 'de' | 'en'
export const DEFAULT_LOCALE: Locale = 'de'
`

writeFileSync(resolve(TYPES_DIR, 'api.ts'), apiFile)
console.log('[extract] Generated api.ts')

// 8. Generate index.ts
const indexFile = `/**
 * @c2s/payload-contracts — Type definitions
 *
 * Re-exports curated types for frontend consumption.
 * Full Payload types available via './payload-types' if needed.
 */

// Collection types (frontend-relevant)
export * from './collections'

// Block types
export * from './blocks'

// Media with helpers
export * from './media'

// API response types
export * from './api'
`

writeFileSync(resolve(TYPES_DIR, 'index.ts'), indexFile)
console.log('[extract] Generated index.ts')

console.log('\n[extract] Done! Generated files in src/types/:')
console.log('  - payload-types.ts  (full copy from CMS)')
console.log('  - collections.ts    (frontend collection re-exports)')
console.log('  - blocks.ts         (block type union + helpers)')
console.log('  - media.ts          (media type + image helpers)')
console.log('  - api.ts            (API response types)')
console.log('  - index.ts          (barrel export)')