package rui import ( "fmt" "sort" "strconv" "strings" ) // ViewStyle interface of the style of view type ViewStyle interface { Properties // Transition returns the transition animation of the property. Returns nil is there is no transition animation. Transition(tag string) Animation // Transitions returns the map of transition animations. The result is always non-nil. Transitions() map[string]Animation // SetTransition sets the transition animation for the property if "animation" argument is not nil, and // removes the transition animation of the property if "animation" argument is nil. // The "tag" argument is the property name. SetTransition(tag string, animation Animation) cssViewStyle(buffer cssBuilder, session Session) } type viewStyle struct { propertyList transitions map[string]Animation } // Range defines range limits. The First and Last value are included in the range type Range struct { First, Last int } type stringWriter interface { writeString(buffer *strings.Builder, indent string) } // String returns a string representation of the Range struct func (r Range) String() string { if r.First == r.Last { return fmt.Sprintf("%d", r.First) } return fmt.Sprintf("%d:%d", r.First, r.Last) } func (r *Range) setValue(value string) bool { var err error if strings.Contains(value, ":") { values := strings.Split(value, ":") if len(values) != 2 { ErrorLog("Invalid range value: " + value) return false } if r.First, err = strconv.Atoi(strings.Trim(values[0], " \t\n\r")); err != nil { ErrorLog(`Invalid first range value "` + value + `" (` + err.Error() + ")") return false } if r.Last, err = strconv.Atoi(strings.Trim(values[1], " \t\n\r")); err != nil { ErrorLog(`Invalid last range value "` + value + `" (` + err.Error() + ")") return false } return true } if r.First, err = strconv.Atoi(value); err != nil { ErrorLog(`Invalid range value "` + value + `" (` + err.Error() + ")") return false } r.Last = r.First return true } func (style *viewStyle) init() { style.propertyList.init() //style.shadows = []ViewShadow{} style.transitions = map[string]Animation{} } // NewViewStyle create new ViewStyle object func NewViewStyle(params Params) ViewStyle { style := new(viewStyle) style.init() for tag, value := range params { style.Set(tag, value) } return style } func (style *viewStyle) cssTextDecoration(session Session) string { buffer := allocStringBuilder() defer freeStringBuilder(buffer) noDecoration := false if strikethrough, ok := boolProperty(style, Strikethrough, session); ok { if strikethrough { buffer.WriteString("line-through") } noDecoration = true } if overline, ok := boolProperty(style, Overline, session); ok { if overline { if buffer.Len() > 0 { buffer.WriteRune(' ') } buffer.WriteString("overline") } noDecoration = true } if underline, ok := boolProperty(style, Underline, session); ok { if underline { if buffer.Len() > 0 { buffer.WriteRune(' ') } buffer.WriteString("underline") } noDecoration = true } if buffer.Len() == 0 && noDecoration { return "none" } return buffer.String() } func split4Values(text string) []string { values := strings.Split(text, ",") count := len(values) switch count { case 1, 4: return values case 2: if strings.Trim(values[1], " \t\r\n") == "" { return values[:1] } case 5: if strings.Trim(values[4], " \t\r\n") != "" { return values[:4] } } return []string{} } func (style *viewStyle) backgroundCSS(session Session) string { if value, ok := style.properties[Background]; ok { if backgrounds, ok := value.([]BackgroundElement); ok { buffer := allocStringBuilder() defer freeStringBuilder(buffer) for _, background := range backgrounds { if value := background.cssStyle(session); value != "" { if buffer.Len() > 0 { buffer.WriteString(", ") } buffer.WriteString(value) } } if buffer.Len() > 0 { return buffer.String() } } } return "" } func (style *viewStyle) cssViewStyle(builder cssBuilder, session Session) { if margin, ok := boundsProperty(style, Margin, session); ok { margin.cssValue(Margin, builder) } if padding, ok := boundsProperty(style, Padding, session); ok { padding.cssValue(Padding, builder) } if border := getBorder(style, Border); border != nil { border.cssStyle(builder, session) border.cssWidth(builder, session) border.cssColor(builder, session) } radius := getRadius(style, session) radius.cssValue(builder) if outline := getOutline(style); outline != nil { outline.ViewOutline(session).cssValue(builder) } if z, ok := intProperty(style, ZIndex, session, 0); ok { builder.add(ZIndex, strconv.Itoa(z)) } if opacity, ok := floatProperty(style, Opacity, session, 1.0); ok && opacity >= 0 && opacity <= 1 { builder.add(Opacity, strconv.FormatFloat(opacity, 'f', 3, 32)) } if n, ok := intProperty(style, ColumnCount, session, 0); ok && n > 0 { builder.add(ColumnCount, strconv.Itoa(n)) } for _, tag := range []string{ Width, Height, MinWidth, MinHeight, MaxWidth, MaxHeight, Left, Right, Top, Bottom, TextSize, TextIndent, LetterSpacing, WordSpacing, LineHeight, TextLineThickness, ListRowGap, ListColumnGap, GridRowGap, GridColumnGap, ColumnGap, ColumnWidth} { if size, ok := sizeProperty(style, tag, session); ok && size.Type != Auto { cssTag, ok := sizeProperties[tag] if !ok { cssTag = tag } builder.add(cssTag, size.cssString("")) } } colorProperties := []struct{ property, cssTag string }{ {BackgroundColor, BackgroundColor}, {TextColor, "color"}, {TextLineColor, "text-decoration-color"}, {CaretColor, CaretColor}, {AccentColor, AccentColor}, } for _, p := range colorProperties { if color, ok := colorProperty(style, p.property, session); ok && color != 0 { builder.add(p.cssTag, color.cssString()) } } if value, ok := enumProperty(style, BackgroundClip, session, 0); ok { builder.add(BackgroundClip, enumProperties[BackgroundClip].values[value]) } if background := style.backgroundCSS(session); background != "" { builder.add("background", background) } if font, ok := stringProperty(style, FontName, session); ok && font != "" { builder.add(`font-family`, font) } writingMode := 0 for _, tag := range []string{ Overflow, TextAlign, TextTransform, TextWeight, TextLineStyle, WritingMode, TextDirection, VerticalTextOrientation, CellVerticalAlign, CellHorizontalAlign, GridAutoFlow, Cursor, WhiteSpace, WordBreak, TextOverflow, Float, TableVerticalAlign, Resize} { if data, ok := enumProperties[tag]; ok { if tag != VerticalTextOrientation || (writingMode != VerticalLeftToRight && writingMode != VerticalRightToLeft) { if value, ok := enumProperty(style, tag, session, 0); ok { cssValue := data.values[value] if cssValue != "" { builder.add(data.cssTag, cssValue) } if tag == WritingMode { writingMode = value } } } } } for _, prop := range []struct{ tag, cssTag, off, on string }{ {tag: Italic, cssTag: "font-style", off: "normal", on: "italic"}, {tag: SmallCaps, cssTag: "font-variant", off: "normal", on: "small-caps"}, } { if flag, ok := boolProperty(style, prop.tag, session); ok { if flag { builder.add(prop.cssTag, prop.on) } else { builder.add(prop.cssTag, prop.off) } } } if tabSize, ok := intProperty(style, TabSize, session, 8); ok && tabSize > 0 { builder.add(TabSize, strconv.Itoa(tabSize)) } if text := style.cssTextDecoration(session); text != "" { builder.add("text-decoration", text) } if userSelect, ok := boolProperty(style, UserSelect, session); ok { if userSelect { builder.add("-webkit-user-select", "auto") builder.add("user-select", "auto") } else { builder.add("-webkit-user-select", "none") builder.add("user-select", "none") } } if css := shadowCSS(style, Shadow, session); css != "" { builder.add("box-shadow", css) } if css := shadowCSS(style, TextShadow, session); css != "" { builder.add("text-shadow", css) } if value, ok := style.properties[ColumnSeparator]; ok { if separator, ok := value.(ColumnSeparatorProperty); ok { if css := separator.cssValue(session); css != "" { builder.add("column-rule", css) } } } if avoid, ok := boolProperty(style, AvoidBreak, session); ok { if avoid { builder.add("break-inside", "avoid") } else { builder.add("break-inside", "auto") } } wrap, _ := enumProperty(style, ListWrap, session, 0) orientation, ok := valueToOrientation(style.Get(Orientation), session) if ok || wrap > 0 { cssText := enumProperties[Orientation].cssValues[orientation] switch wrap { case ListWrapOn: cssText += " wrap" case ListWrapReverse: cssText += " wrap-reverse" } builder.add(`flex-flow`, cssText) } rows := (orientation == StartToEndOrientation || orientation == EndToStartOrientation) var hAlignTag, vAlignTag string if rows { hAlignTag = `justify-content` vAlignTag = `align-items` } else { hAlignTag = `align-items` vAlignTag = `justify-content` } if align, ok := enumProperty(style, HorizontalAlign, session, LeftAlign); ok { switch align { case LeftAlign: if (!rows && wrap == ListWrapReverse) || orientation == EndToStartOrientation { builder.add(hAlignTag, `flex-end`) } else { builder.add(hAlignTag, `flex-start`) } case RightAlign: if (!rows && wrap == ListWrapReverse) || orientation == EndToStartOrientation { builder.add(hAlignTag, `flex-start`) } else { builder.add(hAlignTag, `flex-end`) } case CenterAlign: builder.add(hAlignTag, `center`) case StretchAlign: if rows { builder.add(hAlignTag, `space-between`) } else { builder.add(hAlignTag, `stretch`) } } } if align, ok := enumProperty(style, VerticalAlign, session, LeftAlign); ok { switch align { case TopAlign: if (rows && wrap == ListWrapReverse) || orientation == BottomUpOrientation { builder.add(vAlignTag, `flex-end`) } else { builder.add(vAlignTag, `flex-start`) } case BottomAlign: if (rows && wrap == ListWrapReverse) || orientation == BottomUpOrientation { builder.add(vAlignTag, `flex-start`) } else { builder.add(vAlignTag, `flex-end`) } case CenterAlign: builder.add(vAlignTag, `center`) case StretchAlign: if rows { builder.add(vAlignTag, `stretch`) } else { builder.add(vAlignTag, `space-between`) } } } if r, ok := rangeProperty(style, Row, session); ok { builder.add("grid-row", fmt.Sprintf("%d / %d", r.First+1, r.Last+2)) } if r, ok := rangeProperty(style, Column, session); ok { builder.add("grid-column", fmt.Sprintf("%d / %d", r.First+1, r.Last+2)) } if text := style.gridCellSizesCSS(CellWidth, session); text != "" { builder.add(`grid-template-columns`, text) } if text := style.gridCellSizesCSS(CellHeight, session); text != "" { builder.add(`grid-template-rows`, text) } style.writeViewTransformCSS(builder, session) if clip := getClipShape(style, Clip, session); clip != nil && clip.valid(session) { builder.add(`clip-path`, clip.cssStyle(session)) } if clip := getClipShape(style, ShapeOutside, session); clip != nil && clip.valid(session) { builder.add(`shape-outside`, clip.cssStyle(session)) } if value := style.getRaw(Filter); value != nil { if filter, ok := value.(ViewFilter); ok { if text := filter.cssStyle(session); text != "" { builder.add(Filter, text) } } } if value := style.getRaw(BackdropFilter); value != nil { if filter, ok := value.(ViewFilter); ok { if text := filter.cssStyle(session); text != "" { builder.add(`-webkit-backdrop-filter`, text) builder.add(BackdropFilter, text) } } } if transition := style.transitionCSS(session); transition != "" { builder.add(`transition`, transition) } if animation := style.animationCSS(session); animation != "" { builder.add(AnimationTag, animation) } if pause, ok := boolProperty(style, AnimationPaused, session); ok { if pause { builder.add(`animation-play-state`, `paused`) } else { builder.add(`animation-play-state`, `running`) } } } func valueToOrientation(value any, session Session) (int, bool) { if value != nil { switch value := value.(type) { case int: return value, true case string: text, ok := session.resolveConstants(value) if !ok { return 0, false } text = strings.ToLower(strings.Trim(text, " \t\n\r")) switch text { case "vertical": return TopDownOrientation, true case "horizontal": return StartToEndOrientation, true } if result, ok := enumStringToInt(text, enumProperties[Orientation].values, true); ok { return result, true } } } return 0, false } func (style *viewStyle) Get(tag string) any { return style.get(strings.ToLower(tag)) } func (style *viewStyle) get(tag string) any { switch tag { case Border, CellBorder: return getBorder(&style.propertyList, tag) case BorderLeft, BorderRight, BorderTop, BorderBottom, BorderStyle, BorderLeftStyle, BorderRightStyle, BorderTopStyle, BorderBottomStyle, BorderColor, BorderLeftColor, BorderRightColor, BorderTopColor, BorderBottomColor, BorderWidth, BorderLeftWidth, BorderRightWidth, BorderTopWidth, BorderBottomWidth: if border := getBorder(style, Border); border != nil { return border.Get(tag) } return nil case CellBorderLeft, CellBorderRight, CellBorderTop, CellBorderBottom, CellBorderStyle, CellBorderLeftStyle, CellBorderRightStyle, CellBorderTopStyle, CellBorderBottomStyle, CellBorderColor, CellBorderLeftColor, CellBorderRightColor, CellBorderTopColor, CellBorderBottomColor, CellBorderWidth, CellBorderLeftWidth, CellBorderRightWidth, CellBorderTopWidth, CellBorderBottomWidth: if border := getBorder(style, CellBorder); border != nil { return border.Get(tag) } return nil case RadiusX, RadiusY, RadiusTopLeft, RadiusTopLeftX, RadiusTopLeftY, RadiusTopRight, RadiusTopRightX, RadiusTopRightY, RadiusBottomLeft, RadiusBottomLeftX, RadiusBottomLeftY, RadiusBottomRight, RadiusBottomRightX, RadiusBottomRightY: return getRadiusElement(style, tag) case ColumnSeparator: if val, ok := style.properties[ColumnSeparator]; ok { return val.(ColumnSeparatorProperty) } return nil case ColumnSeparatorStyle, ColumnSeparatorWidth, ColumnSeparatorColor: if val, ok := style.properties[ColumnSeparator]; ok { separator := val.(ColumnSeparatorProperty) return separator.Get(tag) } return nil case Transition: if len(style.transitions) == 0 { return nil } result := map[string]Animation{} for tag, animation := range style.transitions { result[tag] = animation } return result } return style.propertyList.getRaw(tag) } func (style *viewStyle) AllTags() []string { result := style.propertyList.AllTags() if len(style.transitions) > 0 { result = append(result, Transition) } return result } func supportedPropertyValue(value any) bool { switch value.(type) { case string: case []string: case bool: case float32: case float64: case int: case stringWriter: case fmt.Stringer: case []ViewShadow: case []View: case []any: case map[string]Animation: default: return false } return true } func writePropertyValue(buffer *strings.Builder, tag string, value any, indent string) { writeString := func(text string) { simple := (tag != Text && tag != Title && tag != Summary) if simple { if len(text) == 1 { simple = (text[0] >= '0' && text[0] <= '9') || (text[0] >= 'A' && text[0] <= 'Z') || (text[0] >= 'a' && text[0] <= 'z') } else { for _, ch := range text { if (ch >= '0' && ch <= '9') || (ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z') || ch == '+' || ch == '-' || ch == '@' || ch == '/' || ch == '_' || ch == ':' { } else { simple = false break } } } } if !simple { replace := []struct{ old, new string }{ {old: "\\", new: `\\`}, {old: "\t", new: `\t`}, {old: "\r", new: `\r`}, {old: "\n", new: `\n`}, {old: "\"", new: `\"`}, } for _, s := range replace { text = strings.Replace(text, s.old, s.new, -1) } buffer.WriteRune('"') buffer.WriteString(text) buffer.WriteRune('"') } else { buffer.WriteString(text) } } switch value := value.(type) { case string: writeString(value) case []string: if len(value) == 0 { buffer.WriteString("[]") } else { size := 0 for _, text := range value { size += len(text) + 2 } if size < 80 { lead := "[" for _, text := range value { buffer.WriteString(lead) writeString(text) lead = ", " } } else { buffer.WriteString("[\n") for _, text := range value { buffer.WriteString(indent) buffer.WriteRune('\t') writeString(text) buffer.WriteString(",\n") } } buffer.WriteString(indent) buffer.WriteRune(']') } case bool: if value { buffer.WriteString("true") } else { buffer.WriteString("false") } case float32: buffer.WriteString(fmt.Sprintf("%g", float64(value))) case float64: buffer.WriteString(fmt.Sprintf("%g", value)) case int: if prop, ok := enumProperties[tag]; ok && value >= 0 && value < len(prop.values) { buffer.WriteString(prop.values[value]) } else { buffer.WriteString(strconv.Itoa(value)) } case stringWriter: value.writeString(buffer, indent+"\t") case fmt.Stringer: buffer.WriteString(value.String()) case []ViewShadow: switch len(value) { case 0: // do nothing case 1: value[0].writeString(buffer, indent) default: buffer.WriteString("[") indent2 := "\n" + indent + "\t" for _, shadow := range value { buffer.WriteString(indent2) shadow.writeString(buffer, indent) } buffer.WriteRune('\n') buffer.WriteString(indent) buffer.WriteRune(']') } case []View: switch len(value) { case 0: buffer.WriteString("[]\n") case 1: writeViewStyle(value[0].Tag(), value[0], buffer, indent) default: buffer.WriteString("[\n") indent2 := indent + "\t" for _, v := range value { buffer.WriteString(indent2) writeViewStyle(v.Tag(), v, buffer, indent2) buffer.WriteString(",\n") } buffer.WriteString(indent) buffer.WriteRune(']') } case []any: switch count := len(value); count { case 0: buffer.WriteString("[]") case 1: writePropertyValue(buffer, tag, value[0], indent) default: buffer.WriteString("[ ") comma := false for _, v := range value { if comma { buffer.WriteString(", ") } writePropertyValue(buffer, tag, v, indent) comma = true } buffer.WriteString(" ]") } case map[string]Animation: switch count := len(value); count { case 0: buffer.WriteString("[]") case 1: for tag, animation := range value { animation.writeTransitionString(tag, buffer) break } default: tags := make([]string, 0, len(value)) for tag := range value { tags = append(tags, tag) } sort.Strings(tags) buffer.WriteString("[\n") indent2 := indent + "\t" for _, tag := range tags { if animation := value[tag]; animation != nil { buffer.WriteString(indent2) animation.writeTransitionString(tag, buffer) buffer.WriteString(",\n") } } buffer.WriteString(indent) buffer.WriteRune(']') } } } func writeViewStyle(name string, view ViewStyle, buffer *strings.Builder, indent string) { buffer.WriteString(name) buffer.WriteString(" {\n") indent += "\t" writeProperty := func(tag string, value any) { if supportedPropertyValue(value) { buffer.WriteString(indent) buffer.WriteString(tag) buffer.WriteString(" = ") writePropertyValue(buffer, tag, value, indent) buffer.WriteString(",\n") } } tags := view.AllTags() removeTag := func(tag string) { for i, t := range tags { if t == tag { if i == 0 { tags = tags[1:] } else if i == len(tags)-1 { tags = tags[:i] } else { tags = append(tags[:i], tags[i+1:]...) } return } } } tagOrder := []string{ ID, Row, Column, Top, Right, Bottom, Left, Semantics, Cursor, Visibility, Opacity, ZIndex, Width, Height, MinWidth, MinHeight, MaxWidth, MaxHeight, Margin, Padding, BackgroundClip, BackgroundColor, Background, Border, Radius, Outline, Shadow, Orientation, ListWrap, VerticalAlign, HorizontalAlign, CellWidth, CellHeight, CellVerticalAlign, CellHorizontalAlign, ListRowGap, ListColumnGap, GridRowGap, GridColumnGap, ColumnCount, ColumnWidth, ColumnSeparator, ColumnGap, AvoidBreak, Current, Expanded, Side, ResizeBorderWidth, EditViewType, MaxLength, Hint, Text, EditWrap, TextOverflow, FontName, TextSize, TextColor, TextWeight, Italic, SmallCaps, Strikethrough, Overline, Underline, TextLineStyle, TextLineThickness, TextLineColor, TextTransform, TextAlign, WhiteSpace, WordBreak, TextShadow, TextIndent, LetterSpacing, WordSpacing, LineHeight, TextDirection, WritingMode, VerticalTextOrientation, } for _, tag := range tagOrder { if value := view.Get(tag); value != nil { removeTag(tag) writeProperty(tag, value) } } finalTags := []string{ Perspective, PerspectiveOriginX, PerspectiveOriginY, BackfaceVisible, OriginX, OriginY, OriginZ, TranslateX, TranslateY, TranslateZ, ScaleX, ScaleY, ScaleZ, Rotate, RotateX, RotateY, RotateZ, SkewX, SkewY, Clip, Filter, BackdropFilter, Summary, Content, Transition} for _, tag := range finalTags { removeTag(tag) } for _, tag := range tags { if value := view.Get(tag); value != nil { writeProperty(tag, value) } } for _, tag := range finalTags { if value := view.Get(tag); value != nil { writeProperty(tag, value) } } indent = indent[:len(indent)-1] buffer.WriteString(indent) buffer.WriteString("}") } func getViewString(view View) string { buffer := allocStringBuilder() defer freeStringBuilder(buffer) writeViewStyle(view.Tag(), view, buffer, "") return buffer.String() } func runStringWriter(writer stringWriter) string { buffer := allocStringBuilder() defer freeStringBuilder(buffer) writer.writeString(buffer, "") return buffer.String() }