Add annotation modifier

Sources/LiveViewNativeCharts/AxisContent/AxisMarks.swift

@@ -371,7 +371,9 @@ extension Calendar.Component: AttributeDecodable {
         case "nanosecond": self = .nanosecond
         case "calendar": self = .calendar
         case "time_zone": self = .timeZone
+        #if swift(>=5.9)
         case "is_leap_month": self = .isLeapMonth
+        #endif
         default: throw AttributeDecodingError.badValue(Self.self)
         }
     }

Sources/LiveViewNativeCharts/ChartContentBuilder.swift

@@ -25,6 +25,7 @@ struct ChartContentBuilder: ContentBuilder {
     }
 
     enum ModifierType: String, Decodable {
+        case annotation
         case alignsMarkStylesWithPlotArea = "aligns_mark_styles_with_plot_area"
         case cornerRadius = "corner_radius"
         case foregroundStyle = "foreground_style"
@@ -72,6 +73,8 @@ struct ChartContentBuilder: ContentBuilder {
         registry _: R.Type
     ) throws -> any ContentModifier<Self> {
         switch type {
+        case .annotation:
+            return try AnnotationModifier(from: decoder)
         case .alignsMarkStylesWithPlotArea:
             return try AlignsMarkStylesWithPlotAreaModifier(from: decoder)
         case .cornerRadius:

Sources/LiveViewNativeCharts/ChartsRegistry.swift

@@ -25,6 +25,7 @@ public struct ChartsRegistry<Root: RootRegistry>: CustomRegistry {
     }
 
     public enum ModifierType: String {
+        case chartLegend = "chart_legend"
         case chartBackground = "chart_background"
         case chartOverlay = "chart_overlay"
         case chartXAxis = "chart_x_axis"
@@ -33,6 +34,8 @@ public struct ChartsRegistry<Root: RootRegistry>: CustomRegistry {
 
     public static func decodeModifier(_ type: ModifierType, from decoder: Decoder) throws -> some ViewModifier {
         switch type {
+        case .chartLegend:
+            try ChartLegendModifier<Root>(from: decoder)
         case .chartBackground:
             try ChartBackgroundModifier<Root>(from: decoder)
         case .chartOverlay:

Sources/LiveViewNativeCharts/LiveViewNativeCharts.docc/Extensions/AnnotationModifier.md

@@ -0,0 +1,6 @@
+# ``LiveViewNativeCharts/AnnotationModifier``
+
+@Metadata {
+    @DocumentationExtension(mergeBehavior: append)
+    @DisplayName("annotation", style: symbol)
+}

Sources/LiveViewNativeCharts/LiveViewNativeCharts.docc/Extensions/Chart.md

@@ -9,5 +9,9 @@
 ### Axis Modifiers
 - ``ChartXAxisModifier``
 - ``ChartYAxisModifier``
+### Annotating Marks
+- ``AnnotationModifier``
+### Legend Modifiers
+- ``ChartLegendModifier``
 ### Background Modifiers
 - ``ChartBackgroundModifier``

Sources/LiveViewNativeCharts/LiveViewNativeCharts.docc/Extensions/ChartLegendModifier.md

@@ -0,0 +1,6 @@
+# ``LiveViewNativeCharts/ChartLegendModifier``
+
+@Metadata {
+    @DocumentationExtension(mergeBehavior: append)
+    @DisplayName("chart_legend", style: symbol)
+}

Sources/LiveViewNativeCharts/LiveViewNativeCharts.docc/Marks.md

@@ -41,3 +41,4 @@ Each mark supports different values. These attributes are detailed in their docu
 ### Modifiers
 - ``ForegroundStyleModifier``
 - ``OffsetModifier``
+- ``SymbolModifier``

Sources/LiveViewNativeCharts/Modifiers/AnnotationModifier.swift

@@ -0,0 +1,207 @@
+//
+//  AnnotationModifier.swift
+//
+//
+//  Created by Carson.Katri on 6/20/23.
+//
+
+import Charts
+import SwiftUI
+import LiveViewNative
+
+/// Annotate a chart element with custom Views.
+///
+/// Place an annotation on a mark to annotate it.
+/// Provide a key name to the ``content`` argument, and create a nested element with the `template` attribute set to the same key.
+///
+/// ```html
+/// <BarMark
+///   ...
+///   modifiers={@native |> annotation(content: :icon)}
+/// >
+///   <Image template={:icon} system-name="flag.fill" />
+/// </BarMark>
+/// ```
+///
+/// ## Arguments
+/// * ``position``
+/// * ``alignment``
+/// * ``spacing``
+/// * ``content``
+#if swift(>=5.8)
+@_documentation(visibility: public)
+#endif
+struct AnnotationModifier: ContentModifier {
+    typealias Builder = ChartContentBuilder
+
+    /// The position of the annotation with respect to the annotated item. Defaults to `automatic`.
+    ///
+    /// See ``LiveViewNativeCharts/Charts/AnnotationPosition`` for a list of possible values.
+    #if swift(>=5.8)
+    @_documentation(visibility: public)
+    #endif
+    private let position: AnnotationPosition
+
+    /// The alignment of the annotation with respect to the annotated item. Defaults to `center`.
+    ///
+    /// See ``LiveViewNative/SwiftUI/Alignment`` for a list of possible values.
+    #if swift(>=5.8)
+    @_documentation(visibility: public)
+    #endif
+    private let alignment: Alignment
+
+    /// The space between the annotation and the annotated item.
+    #if swift(>=5.8)
+    @_documentation(visibility: public)
+    #endif
+    private let spacing: CGFloat?
+
+    /// `overflow_resolution`, the method used to resolve annotations that do not fit within the chart. Defaults to `automatic`.
+    ///
+    /// See ``OverflowResolution`` for more details.
+    #if swift(>=5.8)
+    @_documentation(visibility: public)
+    #endif
+    private let overflowResolution: OverflowResolution?
+
+    /// The key name of the content to place in the annotation.
+    #if swift(>=5.8)
+    @_documentation(visibility: public)
+    #endif
+    private let content: String
+
+    func apply<R: RootRegistry>(
+        to content: Builder.Content,
+        on element: ElementNode,
+        in context: Builder.Context<R>
+    ) -> Builder.Content {
+        if #available(iOS 17.0, macOS 14.0, tvOS 17.0, watchOS 10.0, *),
+           let overflowResolution = overflowResolution?.value
+        {
+            #if swift(>=5.9)
+            return content
+                .annotation(
+                    position: position,
+                    alignment: alignment,
+                    spacing: spacing,
+                    overflowResolution: overflowResolution
+                ) {
+                    Builder.buildChildViews(of: element, forTemplate: self.content, in: context)
+                }
+            #else
+            let _ = overflowResolution
+            return content
+            #endif
+        } else {
+            return content
+                .annotation(
+                    position: position,
+                    alignment: alignment,
+                    spacing: spacing
+                ) {
+                    Builder.buildChildViews(of: element, forTemplate: self.content, in: context)
+                }
+        }
+    }
+}
+
+/// Resolves an annotation that overflows the chart on the `x`/`y` axes.
+///
+/// Use a tuple where the first element is the `x` strategy is the first element, and the `y` strategy is the second element.
+/// Both elements should contain a ``LiveViewNativeCharts/Charts/AnnotationOverflowResolution/Strategy`` type.
+///
+/// ```elixir
+/// {:automatic, :fit}
+/// ```
+#if swift(>=5.8)
+@_documentation(visibility: public)
+#endif
+struct OverflowResolution: Decodable {
+    let _value: Any
+
+    #if swift(>=5.9)
+    @available(iOS 17.0, macOS 14.0, tvOS 17.0, watchOS 10.0, *)
+    var value: AnnotationOverflowResolution {
+        _value as! AnnotationOverflowResolution
+    }
+    #else
+    var value: Any { fatalError() }
+    #endif
+
+    init(from decoder: Decoder) throws {
+        #if swift(>=5.9)
+        var container = try decoder.unkeyedContainer()
+        if #available(iOS 17.0, macOS 14.0, tvOS 17.0, watchOS 10.0, *) {
+            let x = try container.decode(AnnotationOverflowResolution.Strategy.self)
+            let y = try container.decode(AnnotationOverflowResolution.Strategy.self)
+            self._value = AnnotationOverflowResolution(x: x, y: y)
+        } else {
+            throw DecodingError.dataCorrupted(.init(codingPath: container.codingPath, debugDescription: "AnnotationOverflowResolution is only available on iOS 17, macOS 14, tvOS 17, and watchOS 10 or higher."))
+        }
+        #else
+        fatalError()
+        #endif
+    }
+}
+
+#if swift(>=5.9)
+/// The strategy used to resolve an overflowing annotation.
+///
+/// Possible values:
+/// * `automatic`
+/// * `disabled`
+/// * `fit`, `{:fit, boundary}` - See ``LiveViewNativeCharts/Charts/AnnotationOverflowResolution/Boundary`` for a list of possible values.
+/// * `pad_scale`
+@_documentation(visibility: public)
+@available(iOS 17.0, macOS 14.0, tvOS 17.0, watchOS 10.0, *)
+extension AnnotationOverflowResolution.Strategy: Decodable {
+    public init(from decoder: Decoder) throws {
+        if var container = try? decoder.unkeyedContainer() {
+            switch try container.decode(String.self) {
+            case "fit":
+                self = .fit(to: try container.decode(AnnotationOverflowResolution.Boundary.self))
+            case let `default`:
+                throw DecodingError.dataCorrupted(.init(codingPath: container.codingPath, debugDescription: "Unknown strategy '\(`default`)'"))
+            }
+        } else {
+            let container = try decoder.singleValueContainer()
+            switch try container.decode(String.self) {
+            case "automatic":
+                self = .automatic
+            case "disabled":
+                self = .disabled
+            case "fit":
+                self = .fit
+            case "pad_scale":
+                self = .padScale
+            case let `default`:
+                throw DecodingError.dataCorrupted(.init(codingPath: container.codingPath, debugDescription: "Unknown strategy '\(`default`)'"))
+            }
+        }
+    }
+}
+
+/// The boundary to fit to.
+///
+/// Possible values:
+/// * `automatic`
+/// * `chart`
+/// * `plot`
+@_documentation(visibility: public)
+@available(iOS 17.0, macOS 14.0, tvOS 17.0, watchOS 10.0, *)
+extension AnnotationOverflowResolution.Boundary: Decodable {
+    public init(from decoder: Decoder) throws {
+        let container = try decoder.singleValueContainer()
+        switch try container.decode(String.self) {
+        case "automatic":
+            self = .automatic
+        case "chart":
+            self = .chart
+        case "plot":
+            self = .plot
+        case let `default`:
+            throw DecodingError.dataCorrupted(.init(codingPath: container.codingPath, debugDescription: "Unknown boundary '\(`default`)'"))
+        }
+    }
+}
+#endif