export interface AboutSection {
  title?: string
  paragraphs?: string[]
  items?: string[]
  /** متن HTML از Setting — در صورت وجود، اولویت با این است */
  html?: string
}

const ABOUT_SETTING_KEYS = ['text_about'] as const

export function getAboutSections(projectName: string): AboutSection[] {
  return [
    {
      paragraphs: [`${projectName} وبسایت رسمی است.`],
    },
  ]
}

function looksLikeHtml(value: string) {
  return /<\/?[a-z][\s\S]*>/i.test(value)
}

function parseAboutSettingValue(raw: string): AboutSection[] | null {
  const value = raw.trim()
  if (!value) return null

  try {
    const decoded = JSON.parse(value)
    if (Array.isArray(decoded) && decoded.length > 0) {
      return decoded as AboutSection[]
    }
    if (decoded && typeof decoded === 'object' && typeof decoded.html === 'string') {
      const html = decoded.html.trim()
      if (html) return [{ html }]
    }
    if (decoded && typeof decoded === 'object' && typeof decoded.text === 'string') {
      return parseAboutSettingValue(decoded.text)
    }
  } catch {
    // plain text / html
  }

  if (looksLikeHtml(value)) {
    return [{ html: value }]
  }

  const paragraphs = value
    .split(/\r?\n+/)
    .map((line) => line.trim())
    .filter(Boolean)

  return [{ paragraphs: paragraphs.length > 0 ? paragraphs : [value] }]
}

export function getAboutSettingText(
  getSettingByKey: (key: string) => unknown,
): string {
  for (const key of ABOUT_SETTING_KEYS) {
    const value = String(getSettingByKey(key) ?? '').trim()
    if (value) return value
  }
  return ''
}

/** اولویت با Setting؛ در صورت خالی بودن، متن پیش‌فرض */
export function resolveAboutSections(
  projectName: string,
  settingsText?: string | null,
): AboutSection[] {
  const fromSettings = parseAboutSettingValue(String(settingsText ?? ''))
  if (fromSettings?.length) return fromSettings
  return getAboutSections(projectName)
}