md color classes (.text & .background w/ contrast text)

ng-material-color-classes.js

module.run(($mdColorPalette, $mdTheming) => {
  const { THEMES } = $mdTheming;

  const rules = [];

  for (const themeName in THEMES) {
    const { colors } = THEMES[themeName];

    const themeCls = themeName == 'default' ? '' : `.md-${ themeName }-theme`;

    for (const intention in colors) {
      const intentCls = `.md-${ intention }`;

      const {
        name: color,
        hues: {
          'default': h0,
          'hue-1': h1,
          'hue-2': h2,
          'hue-3': h3
        }
      } = colors[intention];

      const palette = $mdColorPalette[color];

      [ h0, h1, h2, h3 ]
        .map(hue => {
          const { contrast, value } = palette[hue];

          return [ value, contrast ].map(([ ...rgb ]) =>
            `rgb${ rgb.length == 4 ? 'a' : '' }(${ rgb.join(',') })`
          );
        })
        .forEach(([ color, contrast ], i) => {
          const hueCls = i ? `.md-hue-${ i }` : '';

          const selector = [ themeCls, intentCls, hueCls ]
            .filter(n => n)
            .join('');

          const textRule = `${ selector }.text{color:${ color }}`;

          const bgRule = selector +
            `.background{background-color:${ color };color:${ contrast }}`;

          rules.push(textRule, bgRule);
        });
    }
  }

  const style = document.createElement('style');

  document.head.appendChild(style);

  const { sheet } = style;

  rules.forEach(::sheet.insertRule);
});

Usage examples would be nice for those coming from google. Perhaps also explanation what :: is (since it's not ES6 as far as I know)

Edit: FYI, I tried defining a new palette using $mdThemingProvider.definePalette(), and your function failed at line 28 with:

Uncaught TypeError: Cannot read property '500' of undefined