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node_modules/media-engine/src/index.js

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+var Parser = require('./parser');
+
+module.exports = function(queries, options) {
+  var result = {};
+
+  Object.keys(queries).forEach(function(query) {
+    if (Parser.parse(query).match(options)) {
+      Object.assign(result, queries[query]);
+    }
+  });
+
+  return result;
+};

node_modules/media-engine/src/operators.js

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+function And(left, right) {
+  this.left = left;
+  this.right = right;
+
+  this.match = function(options) {
+    return left.match(options) && right.match(options);
+  };
+}
+
+function Or(left, right) {
+  this.left = left;
+  this.right = right;
+
+  this.match = function(options) {
+    return left.match(options) || right.match(options);
+  };
+}
+
+module.exports = function Operator(type, left, right) {
+  switch (type) {
+    case 'and':
+      return new And(left, right);
+    case ',':
+      return new Or(left, right);
+    default:
+      throw new Error(value);
+  }
+};

node_modules/media-engine/src/parser.js

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+var Query = require('./queries');
+var Operator = require('./operators');
+
+var NUMBERS = /[0-9]/;
+var LETTERS = /[a-z|\-]/i;
+var WHITESPACE = /\s/;
+var COLON = /:/;
+var COMMA = /,/;
+var AND = /and$/;
+var AT = /@/;
+
+function tokenizer(input) {
+  var current = 0;
+  var tokens = [];
+
+  while (current < input.length) {
+    var char = input[current];
+
+    if (AT.test(char)) {
+      char = input[++current];
+      while (LETTERS.test(char) && char !== undefined) {
+        char = input[++current];
+      }
+    }
+
+    if (WHITESPACE.test(char) || char === ')' || char === '(') {
+      current++;
+      continue;
+    }
+
+    if (COLON.test(char) || COMMA.test(char)) {
+      current++;
+      tokens.push({ type: 'operator', value: char });
+      continue;
+    }
+
+    if (NUMBERS.test(char)) {
+      var value = '';
+      while (NUMBERS.test(char)) {
+        value += char;
+        char = input[++current];
+      }
+
+      tokens.push({ type: 'number', value: value });
+      continue;
+    }
+
+    if (LETTERS.test(char)) {
+      var value = '';
+      while (LETTERS.test(char) && char !== undefined) {
+        value += char;
+        char = input[++current];
+      }
+      if (AND.test(value)) {
+        tokens.push({ type: 'operator', value: value });
+      } else {
+        tokens.push({ type: 'literal', value: value });
+      }
+
+      continue;
+    }
+
+    throw new TypeError(
+      'Tokenizer: I dont know what this character is: ' + char
+    );
+  }
+
+  return tokens;
+}
+
+function parser(tokens) {
+  var output = [];
+  var stack = [];
+
+  while (tokens.length > 0) {
+    var token = tokens.shift();
+
+    if (token.type === 'number' || token.type === 'literal') {
+      output.push(token);
+      continue;
+    }
+
+    if (token.type === 'operator') {
+      if (COLON.test(token.value)) {
+        token = { type: 'query', key: output.pop(), value: tokens.shift() };
+        output.push(token);
+        continue;
+      }
+
+      while (stack.length > 0) {
+        output.unshift(stack.pop());
+      }
+      stack.push(token);
+    }
+  }
+
+  while (stack.length > 0) {
+    output.unshift(stack.pop());
+  }
+
+  function walk() {
+    var head = output.shift();
+
+    if (head.type === 'number') {
+      return parseInt(head.value);
+    }
+
+    if (head.type === 'literal') {
+      return head.value;
+    }
+
+    if (head.type === 'operator') {
+      var l = walk();
+      var r = walk();
+
+      return Operator(head.value, l, r);
+    }
+
+    if (head.type === 'query') {
+      var l = head.key.value;
+      var r = head.value.value;
+
+      return Query(l, r);
+    }
+  }
+
+  return walk();
+}
+
+module.exports = {
+  parse: function(query) {
+    var tokens = tokenizer(query);
+    var ast = parser(tokens);
+    return ast;
+  }
+};

node_modules/media-engine/src/queries.js

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+function MaxHeight(value) {
+  this.value = value;
+
+  this.match = function(options) {
+    return this.value >= options.height;
+  };
+}
+
+function MinHeight(value) {
+  this.value = value;
+
+  this.match = function(options) {
+    return this.value < options.height;
+  };
+}
+
+function MaxWidth(value) {
+  this.value = value;
+
+  this.match = function(options) {
+    return this.value >= options.width;
+  };
+}
+
+function MinWidth(value) {
+  this.value = value;
+
+  this.match = function(options) {
+    return this.value < options.width;
+  };
+}
+
+function Orientation(value) {
+  this.value = value;
+
+  this.match = function(options) {
+    return this.value === options.orientation;
+  };
+}
+
+module.exports = function Query(type, value) {
+  switch (type) {
+    case 'max-height':
+      return new MaxHeight(value);
+    case 'min-height':
+      return new MinHeight(value);
+    case 'max-width':
+      return new MaxWidth(value);
+    case 'min-width':
+      return new MinWidth(value);
+    case 'orientation':
+      return new Orientation(value);
+    default:
+      throw new Error(value);
+  }
+};