Better handling of Nutriments

Sources/OpenFoodFacts/Schemas/PerlSearchQuery.swift

@@ -0,0 +1,63 @@
+public enum PerlOperator: String {
+	case lt, lte, gt, gte, eq
+}
+
+public enum PerlFormat: String {
+	case json, xml, jqm
+}
+
+public struct SearchNutrimentEntry {
+	public let nutriment: SearchNutriment
+	public let op: PerlOperator
+	public let value: Int
+}
+
+public struct SearchTagsEntry {
+	public let tag: SearchTag
+	public let value: String
+	public let contains: Bool = true
+}
+
+//https://wiki.openfoodfacts.org/API/Read/Search#Parameters
+public struct PerlSearchQuery {
+	public var searchTerms: String
+	public var searchTags: [SearchTagsEntry]?  // tagtype_i=SearchTag — i as #element (starting from 0); (tag_contains_i|tag_does_not_contain_i)=String
+	public var searchNutriment: [SearchNutrimentEntry]?  // nutriment_i=SearchNutriment — i as #element (starting from 0); nutriment_compare_i=PerlOperator; nutriment_value_i=String
+	public var page: Int = 1  // Pagination
+	public var format: PerlFormat  // json=1 | xml=1 | jqm=1
+
+	public init(
+		searchTerms: String, searchTags: [SearchTagsEntry]? = nil,
+		searchNutriment: [SearchNutrimentEntry]? = nil, page: Int = 1,
+		format: PerlFormat = .json
+	) {
+		self.searchTerms = searchTerms
+		self.searchTags = searchTags
+		self.searchNutriment = searchNutriment
+		self.page = page
+		self.format = format
+	}
+
+	public func makeToRequest() -> String {
+		var _searchTags: String?
+		var _searchNutriment: String?
+		let _format: String = "\(format.rawValue)=1"
+		let _page: String = "page=\(page)"
+		if let tags = searchTags {
+			_searchTags = tags.enumerated().map { i, v in
+				return
+					"tagtype_\(i)=\(v.tag.rawValue)&tag_contains_\(i)=\(v.contains ? "contains" : "does_not_contain")&tag_\(i)=\(v.value)"
+			}.joined(separator: "&")
+		}
+		if let nutriments = searchNutriment {
+			_searchNutriment = nutriments.enumerated().map { i, v in
+				return
+					"nutriment_\(i)=\(v.nutriment.rawValue)&nutriment_compare_\(i)=\(v.op.rawValue)&nutriment_value_\(i)=\(v.nutriment.rawValue)"
+			}.joined(separator: "&")
+		}
+
+		return
+			"search_terms=\(searchTerms)\(_searchTags != nil ? "&\(_searchTags!)" : "")\(_searchNutriment != nil ? "&\(_searchNutriment!)" : "")&\(_page)&\(_format)"
+
+	}
+}