import {
  isNumber,
  isPresent,
  isBlank,
  StringWrapper,
  NumberWrapper,
  RegExpWrapper,
  BaseException,
  CONST,
  FunctionWrapper
} from 'angular2/src/facade/lang';
import {NumberFormatter, NumberFormatStyle} from 'angular2/src/facade/intl';
import {ListWrapper} from 'angular2/src/facade/collection';
import {Pipe, BasePipe, PipeFactory} from './pipe';
import {ChangeDetectorRef} from '../change_detector_ref';

var defaultLocale: string = 'en-US';
var _re = RegExpWrapper.create('^(\\d+)?\\.((\\d+)(\\-(\\d+))?)?$');

@CONST()
export class NumberPipe extends BasePipe implements PipeFactory {
  static _format(value: number, style: NumberFormatStyle, digits: string, currency: string = null,
                 currencyAsSymbol: boolean = false): string {
    var minInt = 1, minFraction = 0, maxFraction = 3;
    if (isPresent(digits)) {
      var parts = RegExpWrapper.firstMatch(_re, digits);
      if (isBlank(parts)) {
        throw new BaseException(`${digits} is not a valid digit info for number pipes`);
      }
      if (isPresent(parts[1])) {  // min integer digits
        minInt = NumberWrapper.parseIntAutoRadix(parts[1]);
      }
      if (isPresent(parts[3])) {  // min fraction digits
        minFraction = NumberWrapper.parseIntAutoRadix(parts[3]);
      }
      if (isPresent(parts[5])) {  // max fraction digits
        maxFraction = NumberWrapper.parseIntAutoRadix(parts[5]);
      }
    }
    return NumberFormatter.format(value, defaultLocale, style, {
      minimumIntegerDigits: minInt,
      minimumFractionDigits: minFraction,
      maximumFractionDigits: maxFraction,
      currency: currency,
      currencyAsSymbol: currencyAsSymbol
    });
  }

  supports(obj): boolean { return isNumber(obj); }

  create(cdRef: ChangeDetectorRef): Pipe { return this; }
}

/**
 * Formats a number as local text. i.e. group sizing and seperator and other locale-specific
 * configurations are based on the active locale.
 *
 * # Usage
 *
 *     expression | number[:digitInfo]
 *
 * where `expression` is a number and `digitInfo` has the following format:
 *
 *     {minIntegerDigits}.{minFractionDigits}-{maxFractionDigits}
 *
 * - minIntegerDigits is the minimum number of integer digits to use. Defaults to 1.
 * - minFractionDigits is the minimum number of digits after fraction. Defaults to 0.
 * - maxFractionDigits is the maximum number of digits after fraction. Defaults to 3.
 *
 * For more information on the acceptable range for each of these numbers and other
 * details see your native internationalization library.
 *
 * # Examples
 *
 *     {{ 123 | number }}              // output is 123
 *     {{ 123.1 | number: '.2-3' }}    // output is 123.10
 *     {{ 1 | number: '2.2' }}         // output is 01.00
 */
@CONST()
export class DecimalPipe extends NumberPipe {
  transform(value, args: any[]): string {
    var digits: string = ListWrapper.first(args);
    return NumberPipe._format(value, NumberFormatStyle.DECIMAL, digits);
  }
}

/**
 * Formats a number as local percent.
 *
 * # Usage
 *
 *     expression | percent[:digitInfo]
 *
 * For more information about `digitInfo` see {@link DecimalPipe}
 */
@CONST()
export class PercentPipe extends NumberPipe {
  transform(value, args: any[]): string {
    var digits: string = ListWrapper.first(args);
    return NumberPipe._format(value, NumberFormatStyle.PERCENT, digits);
  }
}

/**
 * Formats a number as local currency.
 *
 * # Usage
 *
 *     expression | currency[:currencyCode[:symbolDisplay[:digitInfo]]]
 *
 * where `currencyCode` is the ISO 4217 currency code, such as "USD" for the US dollar and
 * "EUR" for the euro. `symbolDisplay` is a boolean indicating whether to use the currency
 * symbol (e.g. $) or the currency code (e.g. USD) in the output. The default for this value
 * is `false`.
 * For more information about `digitInfo` see {@link DecimalPipe}
 */
@CONST()
export class CurrencyPipe extends NumberPipe {
  transform(value, args: any[]): string {
    var currencyCode: string = isPresent(args) && args.length > 0 ? args[0] : 'USD';
    var symbolDisplay: boolean = isPresent(args) && args.length > 1 ? args[1] : false;
    var digits: string = isPresent(args) && args.length > 2 ? args[2] : null;
    return NumberPipe._format(value, NumberFormatStyle.CURRENCY, digits, currencyCode,
                              symbolDisplay);
  }
}