| Leo Repp | 58b9f11 | 2021-11-22 11:57:47 +0100 | [diff] [blame^] | 1 | 'use strict' |
| 2 | |
| 3 | module.exports = adapterFactory; |
| 4 | |
| 5 | function adapterFactory(implementation){ |
| 6 | ensureImplementation(implementation); |
| 7 | |
| 8 | var adapter = {} |
| 9 | |
| 10 | var baseAdapter = { |
| 11 | removeSubsets: function (nodes){ |
| 12 | return removeSubsets(adapter, nodes); |
| 13 | }, |
| 14 | existsOne: function(test, elems){ |
| 15 | return existsOne(adapter, test, elems); |
| 16 | }, |
| 17 | getSiblings: function(elem){ |
| 18 | return getSiblings(adapter, elem); |
| 19 | }, |
| 20 | hasAttrib: function(elem, name){ |
| 21 | return hasAttrib(adapter, elem, name); |
| 22 | }, |
| 23 | findOne: function(test, arr){ |
| 24 | return findOne(adapter, test, arr); |
| 25 | }, |
| 26 | findAll: function(test, elems){ |
| 27 | return findAll(adapter, test, elems) |
| 28 | } |
| 29 | }; |
| 30 | |
| 31 | Object.assign(adapter, baseAdapter, implementation); |
| 32 | |
| 33 | return adapter; |
| 34 | } |
| 35 | |
| 36 | var expectImplemented = [ |
| 37 | "isTag", "getAttributeValue", "getChildren", "getName", "getParent", |
| 38 | "getText" |
| 39 | ]; |
| 40 | |
| 41 | function ensureImplementation(implementation){ |
| 42 | if(!implementation) throw new TypeError("Expected implementation") |
| 43 | |
| 44 | var notImplemented = expectImplemented.filter(function(fname){ |
| 45 | return typeof implementation[fname] !== "function"; |
| 46 | }); |
| 47 | |
| 48 | if(notImplemented.length){ |
| 49 | var notList = "(" + notImplemented.join(", ") + ")"; |
| 50 | var message = "Expected functions " + notList + " to be implemented"; |
| 51 | throw new Error(message); |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | function removeSubsets(adapter, nodes){ |
| 56 | var idx = nodes.length, node, ancestor, replace; |
| 57 | |
| 58 | // Check if each node (or one of its ancestors) is already contained in the |
| 59 | // array. |
| 60 | while(--idx > -1){ |
| 61 | node = ancestor = nodes[idx]; |
| 62 | |
| 63 | // Temporarily remove the node under consideration |
| 64 | nodes[idx] = null; |
| 65 | replace = true; |
| 66 | |
| 67 | while(ancestor){ |
| 68 | if(nodes.indexOf(ancestor) > -1){ |
| 69 | replace = false; |
| 70 | nodes.splice(idx, 1); |
| 71 | break; |
| 72 | } |
| 73 | ancestor = adapter.getParent(ancestor) |
| 74 | } |
| 75 | |
| 76 | // If the node has been found to be unique, re-insert it. |
| 77 | if(replace){ |
| 78 | nodes[idx] = node; |
| 79 | } |
| 80 | } |
| 81 | |
| 82 | return nodes; |
| 83 | } |
| 84 | |
| 85 | function existsOne(adapter, test, elems){ |
| 86 | return elems.some(function(elem){ |
| 87 | return adapter.isTag(elem) ? |
| 88 | test(elem) || adapter.existsOne(test, adapter.getChildren(elem)) : |
| 89 | false; |
| 90 | }); |
| 91 | } |
| 92 | |
| 93 | function getSiblings(adapter, elem){ |
| 94 | var parent = adapter.getParent(elem); |
| 95 | return parent && adapter.getChildren(parent); |
| 96 | } |
| 97 | |
| 98 | |
| 99 | function hasAttrib(adapter, elem, name){ |
| 100 | return adapter.getAttributeValue(elem,name) !== undefined |
| 101 | } |
| 102 | |
| 103 | function findOne(adapter, test, arr){ |
| 104 | var elem = null; |
| 105 | |
| 106 | for(var i = 0, l = arr.length; i < l && !elem; i++){ |
| 107 | if(test(arr[i])){ |
| 108 | elem = arr[i]; |
| 109 | } else { |
| 110 | var childs = adapter.getChildren(arr[i]); |
| 111 | if(childs && childs.length > 0){ |
| 112 | elem = adapter.findOne(test, childs); |
| 113 | } |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | return elem; |
| 118 | } |
| 119 | |
| 120 | function findAll(adapter, test, elems){ |
| 121 | var result = []; |
| 122 | |
| 123 | for(var i = 0, j = elems.length; i < j; i++){ |
| 124 | if(!adapter.isTag(elems[i])) continue; |
| 125 | if(test(elems[i])) result.push(elems[i]); |
| 126 | var childs = adapter.getChildren(elems[i]); |
| 127 | if(childs) result = result.concat(adapter.findAll(test, childs)); |
| 128 | } |
| 129 | |
| 130 | return result; |
| 131 | } |