Update Ghostgram features

Swiftgram/SGChatListSimpleSettingsSignal/BUILD

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+filegroup(
+    name = "SGChatListSimpleSettingsSignal",
+    srcs = glob([
+        "Sources/**/*.swift",
+    ]),
+    visibility = [
+        "//visibility:public",
+    ],
+)

Swiftgram/SGChatListSimpleSettingsSignal/Sources/SGChatListSimpleSettingsSignal.swift

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+import SGSimpleSettings
+import Foundation
+import SwiftSignalKit
+
+public func sgSimpleSettingsBoolSignal(_ key: SGSimpleSettings.Keys, defaultValue: Bool) -> Signal<Bool, NoError> {
+    let initial = Signal<Bool, NoError>.single(UserDefaults.standard.object(forKey: key.rawValue) as? Bool ?? defaultValue)
+    let changes = Signal<Bool, NoError> { subscriber in
+        let observer = NotificationCenter.default.addObserver(
+            forName: UserDefaults.didChangeNotification,
+            object: UserDefaults.standard,
+            queue: nil
+        ) { _ in
+            let value = UserDefaults.standard.object(forKey: key.rawValue) as? Bool ?? defaultValue
+            subscriber.putNext(value)
+        }
+        return ActionDisposable {
+            NotificationCenter.default.removeObserver(observer)
+        }
+    }
+    return (initial |> then(changes)) |> distinctUntilChanged
+}

Swiftgram/SGChatListSimpleSettingsSignal/Sources/SGCompactMessagePreviewLayout.swift

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+import SGSimpleSettings
+import CoreGraphics
+import Display
+
+enum SGCompactMessagePreviewLayout {
+    static func isEnabled() -> Bool {
+        (SGSimpleSettings.ChatListLines(rawValue: SGSimpleSettings.shared.chatListLines) ?? .three) != .three
+    }
+
+    static func avatarScaleDivisor(compactChatList: Bool, compactMessagePreview: Bool) -> CGFloat {
+        compactChatList ? 1.5 : (compactMessagePreview ? 1.1 : 1.0)
+    }
+
+    static func forumTopicIconYOffset(compactMessagePreview: Bool) -> CGFloat {
+        compactMessagePreview ? 8.0 : 0.0
+    }
+
+    static func badgeOffset(sizeFactor: CGFloat, compactMessagePreview: Bool, compactChatList: Bool) -> CGFloat {
+        guard compactMessagePreview && !compactChatList else {
+            return 0.0
+        }
+
+        let sizeRange: CGFloat = 0.5
+        let maxLift: CGFloat = 16.0
+        let maxDownshift: CGFloat = 24.0
+        let sizeDelta = sizeFactor - 1.0
+        let lift: CGFloat
+        if sizeDelta >= 0.0 {
+            let sizeGrow = min(sizeRange, sizeDelta)
+            let sizeGrowFactor = sizeGrow / sizeRange
+            lift = maxLift * sizeGrowFactor * sizeGrowFactor * (3.0 - 2.0 * sizeGrowFactor)
+        } else {
+            let sizeShrink = min(sizeRange, -sizeDelta)
+            let sizeShrinkFactor = sizeShrink / sizeRange
+            let downshift = maxDownshift * sizeShrinkFactor * sizeShrinkFactor * (3.0 - 2.0 * sizeShrinkFactor)
+            lift = -downshift
+        }
+
+        return floorToScreenPixels(lift)
+    }
+
+    static func textVerticalOffset(sizeFactor: CGFloat, compactMessagePreview: Bool, compactChatList: Bool, hasAuthorLine: Bool) -> CGFloat {
+        guard compactMessagePreview && !compactChatList && !hasAuthorLine else {
+            return 0.0
+        }
+        return floorToScreenPixels(6.0 * sizeFactor)
+    }
+
+    static func titleTextSpacing(sizeFactor: CGFloat, compactMessagePreview: Bool, compactChatList: Bool, hasAuthorLine: Bool) -> CGFloat {
+        guard compactMessagePreview && !compactChatList && !hasAuthorLine else {
+            return 0.0
+        }
+        return floorToScreenPixels(6.0 * sizeFactor)
+    }
+
+    static func textBlockOffset(sizeFactor: CGFloat, compactMessagePreview: Bool, compactChatList: Bool, hasAuthorLine: Bool) -> CGFloat {
+        textVerticalOffset(sizeFactor: sizeFactor, compactMessagePreview: compactMessagePreview, compactChatList: compactChatList, hasAuthorLine: hasAuthorLine)
+        + titleTextSpacing(sizeFactor: sizeFactor, compactMessagePreview: compactMessagePreview, compactChatList: compactChatList, hasAuthorLine: hasAuthorLine)
+    }
+}