import { hasVisibleText } from './competitionBranding'

export const PARTICIPANT_DEFAULT_PRIMARY = '#052d62'

function primaryHexToRgbTriplet(hex: string): string | null {
  const s = hex.trim().replace('#', '')
  if (!/^[0-9a-f]{6}$/i.test(s)) return null
  const r = parseInt(s.slice(0, 2), 16)
  const g = parseInt(s.slice(2, 4), 16)
  const b = parseInt(s.slice(4, 6), 16)
  return `${r}, ${g}, ${b}`
}

/** 与选手报名端 MainLayout 一致：写入 body 主题色，覆盖 prototype.css 默认洋红 */
export function applyParticipantBodyTheme(themePrimary?: string): void {
  if (typeof document === 'undefined') return
  const custom = themePrimary?.trim() ?? ''
  const theme = hasVisibleText(custom)
    ? /^(?:#|rgb|hsl)/i.test(custom)
      ? custom
      : `#${custom.replace(/^#/, '')}`
    : PARTICIPANT_DEFAULT_PRIMARY
  document.body.style.setProperty('--primary', theme)
  document.body.style.setProperty('--bs-primary', theme)
  if (theme.startsWith('#')) {
    document.body.style.setProperty('--primary-soft', `${theme}14`)
    const rgb = primaryHexToRgbTriplet(theme)
    if (rgb) document.body.style.setProperty('--bs-primary-rgb', rgb)
  } else {
    document.body.style.removeProperty('--primary-soft')
    document.body.style.removeProperty('--bs-primary-rgb')
  }
}

export function clearParticipantBodyTheme(): void {
  if (typeof document === 'undefined') return
  document.body.style.removeProperty('--primary')
  document.body.style.removeProperty('--primary-soft')
  document.body.style.removeProperty('--bs-primary')
  document.body.style.removeProperty('--bs-primary-rgb')
}