var shimConstraints_ = function()

in monitoring-stack-cdk/resources/frontend/connect-rtc.js [6762:6826]
50 lines of code
24 McCabe index (conditional complexity)

      var shimConstraints_ = function(constraints, func) {
        if (browserDetails.version >= 61) {
          return func(constraints);
        }
        constraints = JSON.parse(JSON.stringify(constraints));
        if (constraints && typeof constraints.audio === 'object') {
          var remap = function(obj, a, b) {
            if (a in obj && !(b in obj)) {
              obj[b] = obj[a];
              delete obj[a];
            }
          };
          constraints = JSON.parse(JSON.stringify(constraints));
          remap(constraints.audio, 'autoGainControl', 'googAutoGainControl');
          remap(constraints.audio, 'noiseSuppression', 'googNoiseSuppression');
          constraints.audio = constraintsToChrome_(constraints.audio);
        }
        if (constraints && typeof constraints.video === 'object') {
          // Shim facingMode for mobile & surface pro.
          var face = constraints.video.facingMode;
          face = face && ((typeof face === 'object') ? face : {ideal: face});
          var getSupportedFacingModeLies = browserDetails.version < 66;
    
          if ((face && (face.exact === 'user' || face.exact === 'environment' ||
                        face.ideal === 'user' || face.ideal === 'environment')) &&
              !(navigator.mediaDevices.getSupportedConstraints &&
                navigator.mediaDevices.getSupportedConstraints().facingMode &&
                !getSupportedFacingModeLies)) {
            delete constraints.video.facingMode;
            var matches;
            if (face.exact === 'environment' || face.ideal === 'environment') {
              matches = ['back', 'rear'];
            } else if (face.exact === 'user' || face.ideal === 'user') {
              matches = ['front'];
            }
            if (matches) {
              // Look for matches in label, or use last cam for back (typical).
              return navigator.mediaDevices.enumerateDevices()
              .then(function(devices) {
                devices = devices.filter(function(d) {
                  return d.kind === 'videoinput';
                });
                var dev = devices.find(function(d) {
                  return matches.some(function(match) {
                    return d.label.toLowerCase().indexOf(match) !== -1;
                  });
                });
                if (!dev && devices.length && matches.indexOf('back') !== -1) {
                  dev = devices[devices.length - 1]; // more likely the back cam
                }
                if (dev) {
                  constraints.video.deviceId = face.exact ? {exact: dev.deviceId} :
                                                            {ideal: dev.deviceId};
                }
                constraints.video = constraintsToChrome_(constraints.video);
                logging('chrome: ' + JSON.stringify(constraints));
                return func(constraints);
              });
            }
          }
          constraints.video = constraintsToChrome_(constraints.video);
        }
        logging('chrome: ' + JSON.stringify(constraints));
        return func(constraints);
      };