tElements.coffee

# Helper to interpolate React elements into translation strings
# - created for github.com/fnando/i18n-js
# Assumes:
# > I18n.translations.en = {header: {title: 'Hello %{name}!'}}
# > I18n.locale = 'en'
# Example:
# > tElements('header.title', {name: <em>Thomas</em>})
# > ['Hello ', <em>Thomas</em>, '!']
tElements = (key, variables) ->
  translation = key
    .split('.')
    .reduce(
      (r, k) -> (r || {})[k],
      I18n.translations[I18n.locale]
    )
  return ["[missing \"#{I18n.locale}.#{key}\" translation]"] unless translation

  variableReducer = (r, part) ->
    if part == '%'
      r.variable = true
    else
      r.push if r.variable
        variables[part] || ''
      else
        part
      r.variable = false
    return r

  translation
    .split(/(%)\{([^\{}]+)\}/g)
    .filter(Boolean)
    .reduce(variableReducer, [])