package chart import ( "strings" util "git.gutmet.org/go-chart.git/util" ) // TextHorizontalAlign is an enum for the horizontal alignment options. type TextHorizontalAlign int const ( // TextHorizontalAlignUnset is the unset state for text horizontal alignment. TextHorizontalAlignUnset TextHorizontalAlign = 0 // TextHorizontalAlignLeft aligns a string horizontally so that it's left ligature starts at horizontal pixel 0. TextHorizontalAlignLeft TextHorizontalAlign = 1 // TextHorizontalAlignCenter left aligns a string horizontally so that there are equal pixels // to the left and to the right of a string within a box. TextHorizontalAlignCenter TextHorizontalAlign = 2 // TextHorizontalAlignRight right aligns a string horizontally so that the right ligature ends at the right-most pixel // of a box. TextHorizontalAlignRight TextHorizontalAlign = 3 ) // TextWrap is an enum for the word wrap options. type TextWrap int const ( // TextWrapUnset is the unset state for text wrap options. TextWrapUnset TextWrap = 0 // TextWrapNone will spill text past horizontal boundaries. TextWrapNone TextWrap = 1 // TextWrapWord will split a string on words (i.e. spaces) to fit within a horizontal boundary. TextWrapWord TextWrap = 2 // TextWrapRune will split a string on a rune (i.e. utf-8 codepage) to fit within a horizontal boundary. TextWrapRune TextWrap = 3 ) // TextVerticalAlign is an enum for the vertical alignment options. type TextVerticalAlign int const ( // TextVerticalAlignUnset is the unset state for vertical alignment options. TextVerticalAlignUnset TextVerticalAlign = 0 // TextVerticalAlignBaseline aligns text according to the "baseline" of the string, or where a normal ascender begins. TextVerticalAlignBaseline TextVerticalAlign = 1 // TextVerticalAlignBottom aligns the text according to the lowers pixel of any of the ligatures (ex. g or q both extend below the baseline). TextVerticalAlignBottom TextVerticalAlign = 2 // TextVerticalAlignMiddle aligns the text so that there is an equal amount of space above and below the top and bottom of the ligatures. TextVerticalAlignMiddle TextVerticalAlign = 3 // TextVerticalAlignMiddleBaseline aligns the text veritcally so that there is an equal number of pixels above and below the baseline of the string. TextVerticalAlignMiddleBaseline TextVerticalAlign = 4 // TextVerticalAlignTop alignts the text so that the top of the ligatures are at y-pixel 0 in the container. TextVerticalAlignTop TextVerticalAlign = 5 ) var ( // Text contains utilities for text. Text = &text{} ) // TextStyle encapsulates text style options. type TextStyle struct { HorizontalAlign TextHorizontalAlign VerticalAlign TextVerticalAlign Wrap TextWrap } type text struct{} func (t text) WrapFit(r Renderer, value string, width int, style Style) []string { switch style.TextWrap { case TextWrapRune: return t.WrapFitRune(r, value, width, style) case TextWrapWord: return t.WrapFitWord(r, value, width, style) } return []string{value} } func (t text) WrapFitWord(r Renderer, value string, width int, style Style) []string { style.WriteToRenderer(r) var output []string var line string var word string var textBox Box for _, c := range value { if c == rune('\n') { // commit the line to output output = append(output, t.Trim(line+word)) line = "" word = "" continue } textBox = r.MeasureText(line + word + string(c)) if textBox.Width() >= width { output = append(output, t.Trim(line)) line = word word = string(c) continue } if c == rune(' ') || c == rune('\t') { line = line + word + string(c) word = "" continue } word = word + string(c) } return append(output, t.Trim(line+word)) } func (t text) WrapFitRune(r Renderer, value string, width int, style Style) []string { style.WriteToRenderer(r) var output []string var line string var textBox Box for _, c := range value { if c == rune('\n') { output = append(output, line) line = "" continue } textBox = r.MeasureText(line + string(c)) if textBox.Width() >= width { output = append(output, line) line = string(c) continue } line = line + string(c) } return t.appendLast(output, line) } func (t text) Trim(value string) string { return strings.Trim(value, " \t\n\r") } func (t text) MeasureLines(r Renderer, lines []string, style Style) Box { style.WriteTextOptionsToRenderer(r) var output Box for index, line := range lines { lineBox := r.MeasureText(line) output.Right = util.Math.MaxInt(lineBox.Right, output.Right) output.Bottom += lineBox.Height() if index < len(lines)-1 { output.Bottom += +style.GetTextLineSpacing() } } return output } func (t text) appendLast(lines []string, text string) []string { if len(lines) == 0 { return []string{text} } lastLine := lines[len(lines)-1] lines[len(lines)-1] = lastLine + text return lines }