import type { ChatType } from './types'

type AutoColorValue = string

interface AutoColors {
  mainForeground: AutoColorValue
  mainBackground: AutoColorValue
  greyForeground: AutoColorValue
  greyBackground: AutoColorValue
  menuForeground: AutoColorValue
  menuBackground: AutoColorValue
  inputForeground: AutoColorValue
  inputBackground: AutoColorValue
  buttonForeground: AutoColorValue
  buttonBackground: AutoColorValue
  link: AutoColorValue
  linkHover: AutoColorValue
}

/**
 * @param chatType value of the settings 'chat-type'
 * @param theme value of the settings 'converse-theme'
 * @returns true if the theme can use autocolors
 */
function isAutoColorsAvailable (chatType: ChatType, theme: string): boolean {
  if (chatType !== 'builtin-prosody' && chatType !== 'builtin-converse') {
    return false
  }
  return theme === 'peertube' // currently the only theme that can handle autocolors.
}

/**
 * @param autocolors
 * @returns true if ok. Else a string array with invalid values.
 */
function areAutoColorsValid (autocolors: AutoColors): true | string[] {
  const errors: string[] = []
  for (const k in autocolors) {
    const color = autocolors[k as keyof AutoColors]
    // FIXME: there are missing cases. For now there are only basic values formats.
    if (
      !/^rgb\(\d{1,3},\s*\d{1,3},\s*\d{1,3}\)$/.test(color) &&
      !/^rgba\(\d{1,3},\s*\d{1,3},\s*\d{1,3},\s*(1|0|0?.\d+)\)$/.test(color) &&
      !/^#[0-9a-fA-F]{3,6}$/.test(color) &&
      !/^[a-z]+$/
    ) {
      errors.push(color)
    }
  }
  if (errors.length) {
    return errors
  }
  return true
}

export {
  AutoColors,
  isAutoColorsAvailable,
  areAutoColorsValid
}