Tokamak/Sources/TokamakStaticHTML/Views/HTML.swift

127 lines
3.2 KiB
Swift

// Copyright 2020 Tokamak contributors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
// Created by Max Desiatov on 11/04/2020.
//
import TokamakCore
/** Represents an attribute of an HTML tag. To consume updates from updated attributes, the DOM
renderer needs to know whether the attribute should be assigned via a DOM element property or the
[`setAttribute`](https://developer.mozilla.org/en-US/docs/Web/API/Element/setAttribute) function.
The `isUpdatedAsProperty` flag is used to disambiguate between these two cases.
*/
public struct HTMLAttribute: Hashable {
public let value: String
public let isUpdatedAsProperty: Bool
public init(_ value: String, isUpdatedAsProperty: Bool) {
self.value = value
self.isUpdatedAsProperty = isUpdatedAsProperty
}
public static let value = HTMLAttribute("value", isUpdatedAsProperty: true)
public static let checked = HTMLAttribute("checked", isUpdatedAsProperty: true)
}
extension HTMLAttribute: CustomStringConvertible {
public var description: String { value }
}
extension HTMLAttribute: ExpressibleByStringLiteral {
public init(stringLiteral: String) {
self.init(stringLiteral, isUpdatedAsProperty: false)
}
}
public protocol AnyHTML {
var innerHTML: String? { get }
var tag: String { get }
var attributes: [HTMLAttribute: String] { get }
}
public extension AnyHTML {
var outerHTML: String {
"""
<\(tag)\(attributes.isEmpty ? "" : " ")\
\(attributes.map { #"\#($0)="\#($1)""# }.joined(separator: " "))>\
\(innerHTML ?? "")\
</\(tag)>
"""
}
}
public struct HTML<Content>: View, AnyHTML {
public let tag: String
public let attributes: [HTMLAttribute: String]
let content: Content
public let innerHTML: String?
public var body: Never {
neverBody("HTML")
}
}
public extension HTML where Content: StringProtocol {
init(
_ tag: String,
_ attributes: [HTMLAttribute: String] = [:],
content: Content
) {
self.tag = tag
self.attributes = attributes
self.content = content
innerHTML = String(content)
}
}
extension HTML: ParentView where Content: View {
public init(
_ tag: String,
_ attributes: [HTMLAttribute: String] = [:],
@ViewBuilder content: () -> Content
) {
self.tag = tag
self.attributes = attributes
self.content = content()
innerHTML = nil
}
public var children: [AnyView] {
[AnyView(content)]
}
}
public extension HTML where Content == EmptyView {
init(
_ tag: String,
_ attributes: [HTMLAttribute: String] = [:]
) {
self = HTML(tag, attributes) { EmptyView() }
}
}
public protocol StylesConvertible {
var styles: [String: String] { get }
}
public extension Dictionary {
var inlineStyles: String {
map { "\($0.0): \($0.1);" }
.joined(separator: " ")
}
}