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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
import UIKit
import Fuzi
/**
* OpenSearch XML parser.
*
* This parser accepts standards-compliant OpenSearch 1.1 XML documents in addition to
* the Firefox-specific search plugin format.
*
*/
class OpenSearchParser {
private static let typeSearch = "text/html"
private static let typeSuggest = "application/x-suggestions+json"
private let pluginMode: Bool
init(pluginMode: Bool) {
self.pluginMode = pluginMode
}
func parse(file: URL) -> SearchEngine? {
guard let data = try? Data(contentsOf: file) else {
print("Invalid search file")
return nil
}
guard let doc = try? XMLDocument(data: data),
let rootElem = doc.root else {
print("Invalid XML document")
return nil
}
let shortNameElems = rootElem.children(tag: "ShortName")
guard shortNameElems.count == 1 else {
print("ShortName must appear exactly once")
return nil
}
let shortName = shortNameElems.first!.stringValue
guard !shortName.isEmpty else {
print("ShortName must contain text")
return nil
}
let urlElems = rootElem.children(tag: "Url")
guard !urlElems.isEmpty else {
print("Url must appear at least once")
return nil
}
var searchTemplate: String?
var suggestionsTemplate: String?
for urlElem in urlElems {
guard let type = urlElem.attributes["type"] else {
print("Url element requires a type attribute", terminator: "\n")
return nil
}
guard type == OpenSearchParser.typeSearch || type == OpenSearchParser.typeSuggest else {
// Not a supported search type.
continue
}
guard var template = urlElem.attributes["template"] else {
print("Url element requires a template attribute", terminator: "\n")
return nil
}
if pluginMode {
let paramIndexers = urlElem.children(tag: "Param")
if !paramIndexers.isEmpty {
let params: [String] = paramIndexers.compactMap { indexer in
guard let name = indexer.attr("name"), let value = indexer.attr("value") else {
print("Param element must have name and value attributes", terminator: "\n")
return nil
}
return "\(name)=\(value)"
}
template += "?" + params.joined(separator: "&")
}
}
if type == OpenSearchParser.typeSearch {
searchTemplate = template
} else {
suggestionsTemplate = template
}
}
guard let template = searchTemplate else {
print("Search engine must have a text/html type")
return nil
}
let imageElems = rootElem.children(tag: "Image")
let largestImage: (XMLElement?, Int) = imageElems.reduce((nil, 0)) { result, elem in
// Only accept square images.
guard let widthString = elem.attr("width"),
let heightString = elem.attr("height"),
let width = Int(widthString),
let height = Int(heightString),
width == height && width > result.1 else {
return result
}
return (elem, width)
}
let image: UIImage?
if let imageElem = largestImage.0,
let imageURL = URL(string: imageElem.stringValue, invalidCharacters: false),
let imageData = try? Data(contentsOf: imageURL),
let uiImage = UIImage(data: imageData) {
image = uiImage
} else {
print("Warning: Invalid search image data")
image = nil
}
return SearchEngine(name: shortName, image: image, searchTemplate: template, suggestionsTemplate: suggestionsTemplate)
}
}