import path from 'path'
import { pathToFileURL } from 'url'

export interface TemplateFieldRow {
  label: string
  value: string
}

export interface ParsedSoonTemplate {
  frontImageUrl: string
  backImageUrl: string
  fields: TemplateFieldRow[]
}

function pickArray(obj: Record<string, unknown>, key: string): Record<string, unknown>[] {
  const entry = Object.entries(obj).find(([k]) => k.toLowerCase() === key.toLowerCase())
  if (!Array.isArray(entry?.[1])) return []
  return (entry[1] as unknown[]).filter((x) => x && typeof x === 'object') as Record<string, unknown>[]
}

function pickStr(item: Record<string, unknown>, keys: string[]): string {
  for (const k of keys) {
    const hit = Object.entries(item).find(([name]) => name.toLowerCase() === k.toLowerCase())
    if (hit && hit[1] != null && String(hit[1]).trim()) return String(hit[1]).trim()
  }
  return ''
}

function sideOf(item: Record<string, unknown>): 'front' | 'back' | '' {
  const raw = pickStr(item, ['side', 'face', 'surface', 'cardface']).toLowerCase()
  if (!raw) return ''
  if (['front', '0', 'f', '正面', '正'].includes(raw)) return 'front'
  if (['back', '1', 'b', '背面', '背'].includes(raw)) return 'back'
  return ''
}

function sideLabel(side: 'front' | 'back'): string {
  return side === 'front' ? '正面' : '背面'
}

function resolveAssetPath(soonPath: string, ref: string): string {
  if (!ref) return ''
  const clean = ref.replace(/^file:\/\//i, '')
  const abs = path.isAbsolute(clean) ? clean : path.join(path.dirname(soonPath), clean)
  return pathToFileURL(abs).href
}

function toFieldLabel(name: string, side: 'front' | 'back'): string {
  return `${name} [${sideLabel(side)}]`
}

export function parseSoonTemplate(soonPath: string, raw: Record<string, unknown>): ParsedSoonTemplate {
  const imgs = pickArray(raw, 'Img')
  const texts = pickArray(raw, 'Text')

  let frontImageUrl = ''
  let backImageUrl = ''
  const fields: TemplateFieldRow[] = []

  imgs.forEach((item, idx) => {
    const fileRef = pickStr(item, ['file', 'path', 'img', 'image', 'src', 'filename'])
    if (!fileRef) return
    let side = sideOf(item)
    if (!side) side = idx === 0 ? 'front' : idx === 1 ? 'back' : 'front'
    const url = resolveAssetPath(soonPath, fileRef)
    if (side === 'front') {
      if (!frontImageUrl) frontImageUrl = url
      const name = pickStr(item, ['name', 'field', 'key']) || 'IMAGE'
      fields.push({ label: toFieldLabel(name, 'front'), value: fileRef })
    } else if (!backImageUrl) {
      backImageUrl = url
    }
  })

  texts.forEach((item) => {
    const name = pickStr(item, ['name', 'field', 'key', 'id'])
    if (!name) return
    const value = pickStr(item, ['value', 'text', 'default', 'content', 'data'])
    let side = sideOf(item)
    if (!side) side = /image|img|front/i.test(name) ? 'front' : 'back'
    fields.push({ label: toFieldLabel(name, side), value })
  })

  return { frontImageUrl, backImageUrl, fields }
}