[darwin] Bindings for new 'text-writing-mode' layout property

6 files changed, 189 insertions, 5 deletions

diff --git a/platform/darwin/scripts/generate-style-code.js b/platform/darwin/scripts/generate-style-code.js
index 37454cba54..2a825ac9c7 100755
--- a/platform/darwin/scripts/generate-style-code.js
+++ b/platform/darwin/scripts/generate-style-code.js
@@ -79,6 +79,28 @@ global.camelizeWithLeadingLowercase = function (str) {
     });
 };
 
+// Returns true only if property is an enum or if it is an array
+// property with uniquely defined enum.
+global.definesEnum = function(property, allProperties) {
+    if (property.type === "enum") {
+        return true;
+    }
+
+    if (property.type === 'array' && property.value === 'enum') {
+        const uniqueArrayEnum = (prop, enums) => {
+            if (prop.value !== 'enum') return false;
+            const enumsEqual = (val1, val2) => val1.length === val1.length && val1.every((val, i) => val === val2[i]);
+            return enums.filter(e => enumsEqual(Object.keys(prop.values).sort(), Object.keys(e.values).sort())).length == 0;
+        };
+
+        const allEnumProperties = _(allProperties).filter({'type': 'enum'}).value();
+        const uniqueArrayEnumProperties = _(allProperties).filter({'type': 'array'}).filter(prop => uniqueArrayEnum(prop, allEnumProperties)).value();
+        return _(uniqueArrayEnumProperties).filter({'name': property.name}).value().length != 0;
+    }
+
+    return false;
+}
+
 global.objCName = function (property) {
     return camelizeWithLeadingLowercase(property.name);
 };
@@ -144,6 +166,8 @@ global.objCTestValue = function (property, layerType, arraysAsStructs, indent) {
                 }
                 case 'anchor':
                     return `@"{'top','bottom'}"`;
+                case 'mode':
+                    return `@"{'horizontal','vertical'}"`;
                 default:
                     throw new Error(`unknown array type for ${property.name}`);
             }
@@ -194,6 +218,8 @@ global.mbglTestValue = function (property, layerType) {
                     return '{ 1, 1 }';
                 case 'anchor':
                     return '{ mbgl::style::SymbolAnchorType::Top, mbgl::style::SymbolAnchorType::Bottom }';
+                case 'mode':
+                    return '{ mbgl::style::TextWritingModeType::Horizontal, mbgl::style::TextWritingModeType::Vertical }';
                 default:
                     throw new Error(`unknown array type for ${property.name}`);
             }
@@ -213,6 +239,8 @@ global.mbglExpressionTestValue = function (property, layerType) {
             switch (arrayType(property)) {
                 case 'anchor':
                     return `{"top", "bottom"}`;
+                case 'mode':
+                    return `{"horizontal", "vertical"}`;
                 default:
                     break;
             }
@@ -439,6 +467,8 @@ global.describeType = function (property) {
                     return '`MGLSphericalPosition`';
                 case 'anchor':
                     return '`MGLTextAnchor` array';
+                case 'mode':
+                    return '`MGLTextWritingMode` array';
                 default:
                     return 'array';
             }
@@ -568,6 +598,7 @@ global.propertyType = function (property) {
                 case 'translate':
                     return 'NSValue *';
                 case 'anchor':
+                case 'mode':
                     return 'NSArray<NSValue *> *';
                 default:
                     throw new Error(`unknown array type for ${property.name}`);
@@ -615,6 +646,8 @@ global.valueTransformerArguments = function (property) {
                     return ['std::array<float, 2>', objCType];
                 case 'anchor':
                     return ['std::vector<mbgl::style::SymbolAnchorType>', objCType, 'mbgl::style::SymbolAnchorType', 'MGLTextAnchor'];
+                case 'mode':
+                    return ['std::vector<mbgl::style::TextWritingModeType>', objCType, 'mbgl::style::TextWritingModeType', 'MGLTextWritingMode'];
                 default:
                     throw new Error(`unknown array type for ${property.name}`);
             }
@@ -666,6 +699,8 @@ global.mbglType = function(property) {
                     return 'mbgl::style::Position';
                 case 'anchor':
                     return 'std::vector<mbgl::style::SymbolAnchorType>';
+                case 'mode':
+                    return 'std::vector<mbgl::style::TextWritingModeType>';
                 default:
                     throw new Error(`unknown array type for ${property.name}`);
             }
@@ -773,7 +808,7 @@ var renamedPropertiesByLayerType = {};
 
 for (var layer of layers) {
     layer.properties = _.concat(layer.layoutProperties, layer.paintProperties);
-    let enumProperties = _.filter(layer.properties, prop => prop.type === 'enum');
+    let enumProperties = _.filter(layer.properties, prop => definesEnum(prop, layer.properties));
     if (enumProperties.length) {
         layer.enumProperties = enumProperties;
     }
diff --git a/platform/darwin/src/MGLStyleLayer.h.ejs b/platform/darwin/src/MGLStyleLayer.h.ejs
index 9435e0d2ff..4bbb9e9f0d 100644
--- a/platform/darwin/src/MGLStyleLayer.h.ejs
+++ b/platform/darwin/src/MGLStyleLayer.h.ejs
@@ -19,7 +19,7 @@
 NS_ASSUME_NONNULL_BEGIN
 
 <% for (const property of layoutProperties) { -%>
-<% if (property.type == "enum") { -%>
+<% if (definesEnum(property, layoutProperties)) { -%>
 /**
 <%- propertyDoc(property.name, property, type, 'enum').wrap(80, 1) %>
 
@@ -38,7 +38,7 @@ typedef NS_ENUM(NSUInteger, MGL<%- camelize(property.name) %>) {
 <% } -%>
 <% } -%>
 <% for (const property of paintProperties) { -%>
-<% if (property.type == "enum") { -%>
+<% if (definesEnum(property, paintProperties)) { -%>
 /**
 <%- propertyDoc(property.name, property, type, 'enum').wrap(80, 1) %>
 
diff --git a/platform/darwin/src/MGLStyleLayer.mm.ejs b/platform/darwin/src/MGLStyleLayer.mm.ejs
index 26cb3e26f6..e8c8d8cfd9 100644
--- a/platform/darwin/src/MGLStyleLayer.mm.ejs
+++ b/platform/darwin/src/MGLStyleLayer.mm.ejs
@@ -25,7 +25,7 @@ namespace mbgl {
 
 <% if (layoutProperties.length) { -%>
 <% for (const property of layoutProperties) { -%>
-<% if (property.type == "enum") { -%>
+<% if (definesEnum(property, layoutProperties)) { -%>
     MBGL_DEFINE_ENUM(MGL<%- camelize(property.name) %>, {
 <% for (const value in property.values) { -%>
         { MGL<%- camelize(property.name) %><%- camelize(value) %>, "<%-value%>" },
@@ -37,7 +37,7 @@ namespace mbgl {
 <% } -%>
 <% if (paintProperties.length) { -%>
 <% for (const property of paintProperties) { -%>
-<% if (property.type == "enum") { -%>
+<% if (definesEnum(property, paintProperties)) { -%>
     MBGL_DEFINE_ENUM(MGL<%- camelize(property.name) %>, {
 <% for (const value in property.values) { -%>
         { MGL<%- camelize(property.name) %><%- camelize(value) %>, "<%-value%>" },
diff --git a/platform/darwin/src/MGLSymbolStyleLayer.h b/platform/darwin/src/MGLSymbolStyleLayer.h
index 658a31679e..bbb5dae905 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.h
+++ b/platform/darwin/src/MGLSymbolStyleLayer.h
@@ -317,6 +317,30 @@ typedef NS_ENUM(NSUInteger, MGLTextTransform) {
 };
 
 /**
+ The property allows to control an orientation of a symbol. Note, that the
+ property values act as a hint, so that Symbols whose language doesn't support
+ provided orientation, will be laid out in their natural orientation. Example:
+ English point symbol will be rendered horizontally even if `"textWritingMode":
+ ["vertical"]` is set. The order of elements in an array define priority order
+ for the placement of an orientation variant.
+
+ Values of this type are used in the `MGLSymbolStyleLayer.textWritingMode`
+ property.
+ */
+typedef NS_ENUM(NSUInteger, MGLTextWritingMode) {
+    /**
+     If a text's language supports horizontal writing mode, symbols with point
+     placement would be laid out horizontally.
+     */
+    MGLTextWritingModeHorizontal,
+    /**
+     If a text's language supports vertical writing mode, symbols with point
+     placement would be laid out vertically.
+     */
+    MGLTextWritingModeVertical,
+};
+
+/**
  Controls the frame of reference for `MGLSymbolStyleLayer.iconTranslation`.
 
  Values of this type are used in the `MGLSymbolStyleLayer.iconTranslationAnchor`
@@ -1646,6 +1670,38 @@ MGL_EXPORT
  */
 @property (nonatomic, null_resettable) NSExpression *textVariableAnchor;
 
+/**
+ The property allows to control an orientation of a symbol. Note, that the
+ property values act as a hint, so that Symbols whose language doesn't support
+ provided orientation, will be laid out in their natural orientation. Example:
+ English point symbol will be rendered horizontally even if `"textWritingMode":
+ ["vertical"]` is set. The order of elements in an array define priority order
+ for the placement of an orientation variant.
+ 
+ This property is only applied to the style if `text` is non-`nil`, and
+ `symbolPlacement` is set to an expression that evaluates to or
+ `MGLSymbolPlacementPoint`. Otherwise, it is ignored.
+ 
+ You can set this property to an expression containing any of the following:
+ 
+ * Constant `MGLTextWritingMode` array values
+ * Constant array, whose each element is any of the following constant string
+ values:
+   * `horizontal`: If a text's language supports horizontal writing mode,
+ symbols with point placement would be laid out horizontally.
+   * `vertical`: If a text's language supports vertical writing mode, symbols
+ with point placement would be laid out vertically.
+ * Predefined functions, including mathematical and string operators
+ * Conditional expressions
+ * Variable assignments and references to assigned variables
+ * Step functions applied to the `$zoomLevel` variable
+ 
+ This property does not support applying interpolation functions to the
+ `$zoomLevel` variable or applying interpolation or step functions to feature
+ attributes.
+ */
+@property (nonatomic, null_resettable) NSExpression *textWritingMode;
+
 #pragma mark - Accessing the Paint Attributes
 
 #if TARGET_OS_IPHONE
@@ -2383,6 +2439,19 @@ MGL_EXPORT
 @property (readonly) MGLTextTransform MGLTextTransformValue;
 
 /**
+ Creates a new value object containing the given `MGLTextWritingMode` enumeration.
+
+ @param textWritingMode The value for the new object.
+ @return A new value object that contains the enumeration value.
+ */
++ (instancetype)valueWithMGLTextWritingMode:(MGLTextWritingMode)textWritingMode;
+
+/**
+ The `MGLTextWritingMode` enumeration representation of the value.
+ */
+@property (readonly) MGLTextWritingMode MGLTextWritingModeValue;
+
+/**
  Creates a new value object containing the given `MGLIconTranslationAnchor` enumeration.
 
  @param iconTranslationAnchor The value for the new object.
diff --git a/platform/darwin/src/MGLSymbolStyleLayer.mm b/platform/darwin/src/MGLSymbolStyleLayer.mm
index e54a0b9a15..99cfe5db10 100644
--- a/platform/darwin/src/MGLSymbolStyleLayer.mm
+++ b/platform/darwin/src/MGLSymbolStyleLayer.mm
@@ -96,6 +96,11 @@ namespace mbgl {
         { MGLTextTransformLowercase, "lowercase" },
     });
 
+    MBGL_DEFINE_ENUM(MGLTextWritingMode, {
+        { MGLTextWritingModeHorizontal, "horizontal" },
+        { MGLTextWritingModeVertical, "vertical" },
+    });
+
     MBGL_DEFINE_ENUM(MGLIconTranslationAnchor, {
         { MGLIconTranslationAnchorMap, "map" },
         { MGLIconTranslationAnchorViewport, "viewport" },
@@ -1023,6 +1028,24 @@ namespace mbgl {
     return MGLStyleValueTransformer<std::vector<mbgl::style::SymbolAnchorType>, NSArray<NSValue *> *, mbgl::style::SymbolAnchorType, MGLTextAnchor>().toExpression(propertyValue);
 }
 
+- (void)setTextWritingMode:(NSExpression *)textWritingMode {
+    MGLAssertStyleLayerIsValid();
+    MGLLogDebug(@"Setting textWritingMode: %@", textWritingMode);
+
+    auto mbglValue = MGLStyleValueTransformer<std::vector<mbgl::style::TextWritingModeType>, NSArray<NSValue *> *, mbgl::style::TextWritingModeType, MGLTextWritingMode>().toPropertyValue<mbgl::style::PropertyValue<std::vector<mbgl::style::TextWritingModeType>>>(textWritingMode, false);
+    self.rawLayer->setTextWritingMode(mbglValue);
+}
+
+- (NSExpression *)textWritingMode {
+    MGLAssertStyleLayerIsValid();
+
+    auto propertyValue = self.rawLayer->getTextWritingMode();
+    if (propertyValue.isUndefined()) {
+        propertyValue = self.rawLayer->getDefaultTextWritingMode();
+    }
+    return MGLStyleValueTransformer<std::vector<mbgl::style::TextWritingModeType>, NSArray<NSValue *> *, mbgl::style::TextWritingModeType, MGLTextWritingMode>().toExpression(propertyValue);
+}
+
 #pragma mark - Accessing the Paint Attributes
 
 - (void)setIconColor:(NSExpression *)iconColor {
@@ -1599,6 +1622,16 @@ namespace mbgl {
     return textTransform;
 }
 
++ (NSValue *)valueWithMGLTextWritingMode:(MGLTextWritingMode)textWritingMode {
+    return [NSValue value:&textWritingMode withObjCType:@encode(MGLTextWritingMode)];
+}
+
+- (MGLTextWritingMode)MGLTextWritingModeValue {
+    MGLTextWritingMode textWritingMode;
+    [self getValue:&textWritingMode];
+    return textWritingMode;
+}
+
 + (NSValue *)valueWithMGLIconTranslationAnchor:(MGLIconTranslationAnchor)iconTranslationAnchor {
     return [NSValue value:&iconTranslationAnchor withObjCType:@encode(MGLIconTranslationAnchor)];
 }
diff --git a/platform/darwin/test/MGLSymbolStyleLayerTests.mm b/platform/darwin/test/MGLSymbolStyleLayerTests.mm
index 87091acc1b..0f51fd000c 100644
--- a/platform/darwin/test/MGLSymbolStyleLayerTests.mm
+++ b/platform/darwin/test/MGLSymbolStyleLayerTests.mm
@@ -2074,6 +2074,50 @@
         XCTAssertThrowsSpecificNamed(layer.textVariableAnchor = functionExpression, NSException, NSInvalidArgumentException, @"MGLSymbolLayer should raise an exception if a camera-data expression is applied to a property that does not support key paths to feature attributes.");
     }
 
+    // text-writing-mode
+    {
+        XCTAssertTrue(rawLayer->getTextWritingMode().isUndefined(),
+                      @"text-writing-mode should be unset initially.");
+        NSExpression *defaultExpression = layer.textWritingMode;
+
+        NSExpression *constantExpression = [NSExpression expressionWithFormat:@"{'horizontal','vertical'}"];
+        layer.textWritingMode = constantExpression;
+        mbgl::style::PropertyValue<std::vector<mbgl::style::TextWritingModeType>> propertyValue = { { mbgl::style::TextWritingModeType::Horizontal, mbgl::style::TextWritingModeType::Vertical } };
+        XCTAssertEqual(rawLayer->getTextWritingMode(), propertyValue,
+                       @"Setting textWritingMode to a constant value expression should update text-writing-mode.");
+        XCTAssertEqualObjects(layer.textWritingMode, constantExpression,
+                              @"textWritingMode should round-trip constant value expressions.");
+
+        constantExpression = [NSExpression expressionWithFormat:@"{'horizontal','vertical'}"];
+        NSExpression *functionExpression = [NSExpression expressionWithFormat:@"mgl_step:from:stops:($zoomLevel, %@, %@)", constantExpression, @{@18: constantExpression}];
+        layer.textWritingMode = functionExpression;
+
+        {
+            using namespace mbgl::style::expression::dsl;
+            propertyValue = mbgl::style::PropertyExpression<std::vector<mbgl::style::TextWritingModeType>>(
+                step(zoom(), literal({"horizontal", "vertical"}), 18.0, literal({"horizontal", "vertical"}))
+            );
+        }
+
+        XCTAssertEqual(rawLayer->getTextWritingMode(), propertyValue,
+                       @"Setting textWritingMode to a camera expression should update text-writing-mode.");
+        XCTAssertEqualObjects(layer.textWritingMode, functionExpression,
+                              @"textWritingMode should round-trip camera expressions.");
+
+
+        layer.textWritingMode = nil;
+        XCTAssertTrue(rawLayer->getTextWritingMode().isUndefined(),
+                      @"Unsetting textWritingMode should return text-writing-mode to the default value.");
+        XCTAssertEqualObjects(layer.textWritingMode, defaultExpression,
+                              @"textWritingMode should return the default value after being unset.");
+
+        functionExpression = [NSExpression expressionForKeyPath:@"bogus"];
+        XCTAssertThrowsSpecificNamed(layer.textWritingMode = functionExpression, NSException, NSInvalidArgumentException, @"MGLSymbolLayer should raise an exception if a camera-data expression is applied to a property that does not support key paths to feature attributes.");
+        functionExpression = [NSExpression expressionWithFormat:@"mgl_step:from:stops:(bogus, %@, %@)", constantExpression, @{@18: constantExpression}];
+        functionExpression = [NSExpression expressionWithFormat:@"mgl_interpolate:withCurveType:parameters:stops:($zoomLevel, 'linear', nil, %@)", @{@10: functionExpression}];
+        XCTAssertThrowsSpecificNamed(layer.textWritingMode = functionExpression, NSException, NSInvalidArgumentException, @"MGLSymbolLayer should raise an exception if a camera-data expression is applied to a property that does not support key paths to feature attributes.");
+    }
+
     // icon-color
     {
         XCTAssertTrue(rawLayer->getIconColor().isUndefined(),
@@ -3084,6 +3128,7 @@
     [self testPropertyName:@"text-rotation-alignment" isBoolean:NO];
     [self testPropertyName:@"text-transform" isBoolean:NO];
     [self testPropertyName:@"text-variable-anchor" isBoolean:NO];
+    [self testPropertyName:@"text-writing-mode" isBoolean:NO];
     [self testPropertyName:@"icon-color" isBoolean:NO];
     [self testPropertyName:@"icon-halo-blur" isBoolean:NO];
     [self testPropertyName:@"icon-halo-color" isBoolean:NO];
@@ -3148,6 +3193,8 @@
     XCTAssertEqual([NSValue valueWithMGLTextTransform:MGLTextTransformNone].MGLTextTransformValue, MGLTextTransformNone);
     XCTAssertEqual([NSValue valueWithMGLTextTransform:MGLTextTransformUppercase].MGLTextTransformValue, MGLTextTransformUppercase);
     XCTAssertEqual([NSValue valueWithMGLTextTransform:MGLTextTransformLowercase].MGLTextTransformValue, MGLTextTransformLowercase);
+    XCTAssertEqual([NSValue valueWithMGLTextWritingMode:MGLTextWritingModeHorizontal].MGLTextWritingModeValue, MGLTextWritingModeHorizontal);
+    XCTAssertEqual([NSValue valueWithMGLTextWritingMode:MGLTextWritingModeVertical].MGLTextWritingModeValue, MGLTextWritingModeVertical);
     XCTAssertEqual([NSValue valueWithMGLIconTranslationAnchor:MGLIconTranslationAnchorMap].MGLIconTranslationAnchorValue, MGLIconTranslationAnchorMap);
     XCTAssertEqual([NSValue valueWithMGLIconTranslationAnchor:MGLIconTranslationAnchorViewport].MGLIconTranslationAnchorValue, MGLIconTranslationAnchorViewport);
     XCTAssertEqual([NSValue valueWithMGLTextTranslationAnchor:MGLTextTranslationAnchorMap].MGLTextTranslationAnchorValue, MGLTextTranslationAnchorMap);