/*
 * Copyright 2015, Yahoo Inc.
 * Copyrights licensed under the New BSD License.
 * See the accompanying LICENSE file for terms.
 */

import {
  MessageFormatElement,
  isLiteralElement,
  LiteralElement,
  ArgumentElement,
  DateElement,
  TimeElement,
  NumberElement,
  SelectElement,
  PluralElement,
  isSelectElement,
  isArgumentElement,
  isDateElement,
  isTimeElement,
  isNumberElement,
  isPluralElement,
  TYPE
} from './types';

const ESCAPED_CHARS: Record<string, string> = {
  '\\': '\\\\',
  '\\#': '\\#',
  '{': '\\{',
  '}': '\\}'
};

const ESAPE_CHARS_REGEXP = /\\#|[{}\\]/g;

export function printAST(ast: MessageFormatElement[]): string {
  let printedNodes = ast.map(el => {
    if (isLiteralElement(el)) {
      return printLiteralElement(el);
    }

    if (isArgumentElement(el)) {
      return printArgumentElement(el);
    }
    if (isDateElement(el) || isTimeElement(el) || isNumberElement(el)) {
      return printSimpleFormatElement(el);
    }

    if (isPluralElement(el)) {
      return printPluralElement(el);
    }

    if (isSelectElement(el)) {
      return printSelectElement(el);
    }
  });

  return printedNodes.join('');
}

function printLiteralElement({ value }: LiteralElement) {
  return value.replace(ESAPE_CHARS_REGEXP, char => ESCAPED_CHARS[char]);
}

function printArgumentElement({ value }: ArgumentElement) {
  return `{${value}}`;
}

function printSimpleFormatElement(
  el: DateElement | TimeElement | NumberElement
) {
  return `{${el.value}, ${TYPE[el.type]}${el.style ? `, ${el.style}` : ''}}`;
}
function printSelectElement(el: SelectElement) {
  const msg = [
    el.value,
    'select',
    Object.keys(el.options)
      .map(id => `${id}{${printAST(el.options[id].value)}}`)
      .join(' ')
  ].join(',');
  return `{${msg}}`;
}

function printPluralElement(el: PluralElement) {
  const type = el.pluralType === 'cardinal' ? 'plural' : 'selectordinal';
  const msg = [
    el.value,
    type,
    [
      el.offset ? `offset:${el.offset}` : '',
      ...Object.keys(el.options).map(
        id => `${id}{${printAST(el.options[id].value)}}`
      )
    ]
      .filter(Boolean)
      .join(' ')
  ].join(',');
  return `{${msg}}`;
}