Adding Blocks support

SKCore/Sources/BlockComposition.swift

@@ -0,0 +1,96 @@
+/// Defined by https://api.slack.com/reference/messaging/composition-objects#text
+public struct TextComposition {
+    /// The type of block. Can be one of plainText or markdown.
+    public let type: BlockType
+    public let text: String
+    public let emoji: Bool?
+    public let verbatim: Bool?
+
+    public init(type: BlockType,
+                text: String,
+                emoji: Bool? = nil,
+                verbatim: Bool? = nil) {
+        self.type = type
+        self.text = text
+        self.emoji = emoji
+        self.verbatim = verbatim
+    }
+
+    public var dictionary: [String: Any] {
+        var composition = [String: Any]()
+        composition["type"] = type.rawValue
+        composition["text"] = text
+        composition["emoji"] = emoji
+        composition["verbatim"] = verbatim
+        return composition
+    }
+}
+
+/// Defined by https://api.slack.com/reference/messaging/composition-objects#option
+public struct OptionComposition {
+    public let text: TextComposition
+    public let value: String
+    public let url: String?
+
+    public init(text: TextComposition,
+                value: String,
+                url: String? = nil) {
+        self.text = text
+        self.value = value
+        self.url = url
+    }
+
+    public var dictionary: [String: Any] {
+        var composition = [String: Any]()
+        composition["text"] = text.dictionary
+        composition["value"] = value
+        composition["url"] = url
+        return composition
+    }
+}
+
+/// Defined by https://api.slack.com/reference/messaging/composition-objects#option-group
+public struct OptionGroupComposition {
+    public let label: TextComposition
+    public let options: [OptionComposition]
+
+    public init(label: TextComposition,
+                options: [OptionComposition]) {
+        self.label = label
+        self.options = options
+    }
+
+    public var dictionary: [String: Any] {
+        var composition = [String: Any]()
+        composition["label"] = label.dictionary
+        composition["options"] = options.map { $0.dictionary }
+        return composition
+    }
+}
+
+/// Defined by https://api.slack.com/reference/messaging/composition-objects#confirm
+public struct ConfirmComposition {
+    public let title: TextComposition
+    public let text: TextComposition
+    public let confirm: TextComposition
+    public let deny: TextComposition
+
+    public init(title: TextComposition,
+                text: TextComposition,
+                confirm: TextComposition,
+                deny: TextComposition) {
+        self.title = title
+        self.text = text
+        self.confirm = confirm
+        self.deny = deny
+    }
+
+    public var dictionary: [String: Any] {
+        var composition = [String: Any]()
+        composition["title"] = title.dictionary
+        composition["text"] = text.dictionary
+        composition["confirm"] = confirm.dictionary
+        composition["deny"] = deny.dictionary
+        return composition
+    }
+}