MyEMS / myems

if (typeof module !== 'undefined' &&

    typeof exports !== 'undefined' &&

    module.exports === exports){

  module.exports = 'monospaced.qrcode';

}

angular.module('monospaced.qrcode', [])

  .directive('qrcode', ['$window', function($window) {

    var canvas2D = !!$window.CanvasRenderingContext2D,

        levels = {

          'L': 'Low',

          'M': 'Medium',

          'Q': 'Quartile',

          'H': 'High'

        },

        draw = function(context, qr, modules, tile, color) {

          for (var row = 0; row < modules; row++) {

            for (var col = 0; col < modules; col++) {

              var w = (Math.ceil((col + 1) * tile) - Math.floor(col * tile)),

                  h = (Math.ceil((row + 1) * tile) - Math.floor(row * tile));

              context.fillStyle = qr.isDark(row, col) ? color.foreground : color.background;

              context.fillRect(Math.round(col * tile),

                               Math.round(row * tile), w, h);

            }

          }

        };

    return {

      restrict: 'E',

      template: '<canvas class="qrcode"></canvas>',

      link: function(scope, element, attrs) {

        var domElement = element[0],

            $canvas = element.find('canvas'),

            canvas = $canvas[0],

            context = canvas2D ? canvas.getContext('2d') : null,

            download = 'download' in attrs,

            href = attrs.href,

            link = download || href ? document.createElement('a') : '',

            trim = /^\s+|\s+$/g,

            error,

            version,

            errorCorrectionLevel,

            data,

            size,

            modules,

            tile,

            qr,

            $img,

            color = {

              foreground: '#000',

              background: '#fff'

            },

            setColor = function(value) {

              color.foreground = value || color.foreground;

            },

            setBackground = function(value) {

              color.background = value || color.background;

            },

            setVersion = function(value) {

              version = Math.max(1, Math.min(parseInt(value, 10), 40)) || 5;

            },

            setErrorCorrectionLevel = function(value) {

              errorCorrectionLevel = value in levels ? value : 'M';

            },

            setData = function(value) {

              if (!value) {

                return;

              }

              data = value.replace(trim, '');

              qr = qrcode(version, errorCorrectionLevel);

              qr.addData(data);

              try {

                qr.make();

              } catch (e) {

                var newVersion;

                if (version >= 40) {

                  throw new Error('Data is too long', e);

                }

                newVersion = version + 1;

                setVersion(newVersion);

                console.warn('qrcode version is too low and has been incremented to', newVersion)

                setData(value);

                return;

              }

              error = false;

              modules = qr.getModuleCount();

            },

            setSize = function(value) {

              size = parseInt(value, 10) || modules * 2;

              tile = size / modules;

              canvas.width = canvas.height = size;

            },

            render = function() {

              if (!qr) {

                return;

              }

              if (error) {

                if (link) {

                  link.removeAttribute('download');

                  link.title = '';

                  link.href = '#_';

                }

                if (!canvas2D) {

                  domElement.innerHTML = '<img src width="' + size + '"' +

                                         'height="' + size + '"' +

                                         'class="qrcode">';

                }

                scope.$emit('qrcode:error', error);

                return;

              }

              if (download) {

                domElement.download = 'qrcode.png';

                domElement.title = 'Download QR code';

              }

              if (canvas2D) {

                draw(context, qr, modules, tile, color);

                if (download) {

                  domElement.href = canvas.toDataURL('image/png');

                  return;

                }

              } else {

                domElement.innerHTML = qr.createImgTag(tile, 0);

                $img = element.find('img');

                $img.addClass('qrcode');

                if (download) {

                  domElement.href = $img[0].src;

                  return;

                }

              }

              if (href) {

                domElement.href = href;

              }

            };

        if (link) {

          link.className = 'qrcode-link';

          $canvas.wrap(link);

          domElement = domElement.firstChild;

        }

        setColor(attrs.color);

        setBackground(attrs.background);

        setVersion(attrs.version);

        setErrorCorrectionLevel(attrs.errorCorrectionLevel);

        setSize(attrs.size);

        attrs.$observe('version', function(value) {

          if (!value) {

            return;

          }

          setVersion(value);

          setData(data);

          setSize(size);

          render();

        });

        attrs.$observe('errorCorrectionLevel', function(value) {

          if (!value) {

            return;

          }

          setErrorCorrectionLevel(value);

          setData(data);

          setSize(size);

          render();

        });

        attrs.$observe('data', function(value) {

          if (!value) {

            return;

          }

          setData(value);

          setSize(size);

          render();

        });

        attrs.$observe('size', function(value) {

          if (!value) {

            return;

          }

          setSize(value);

          render();

        });

        attrs.$observe('color', function(value) {

          if (!value) {

            return;

          }

          setColor(value);

          render();

        });

        attrs.$observe('background', function(value) {

          if (!value) {

            return;

          }

          setBackground(value);

          render();

        });

        attrs.$observe('href', function(value) {

          if (!value) {

            return;

          }

          href = value;

          render();

        });

      }

    };

  }]);