Start refactor

cmd/micro/window.go

@@ -0,0 +1,187 @@
+package main
+
+import (
+	"strconv"
+	"unicode/utf8"
+
+	runewidth "github.com/mattn/go-runewidth"
+	"github.com/zyedidia/tcell"
+)
+
+type Window struct {
+	// X and Y coordinates for the top left of the window
+	X int
+	Y int
+
+	// Width and Height for the window
+	Width  int
+	Height int
+
+	// Which line in the buffer to start displaying at (vertical scroll)
+	StartLine int
+	// Which visual column in the to start displaying at (horizontal scroll)
+	StartCol int
+
+	// Buffer being shown in this window
+	Buf *Buffer
+
+	sline *StatusLine
+}
+
+func NewWindow(x, y, width, height int, buf *Buffer) *Window {
+	w := new(Window)
+	w.X, w.Y, w.Width, w.Height, w.Buf = x, y, width, height, buf
+
+	w.sline = NewStatusLine(w)
+
+	return w
+}
+
+func (w *Window) DrawLineNum(lineNumStyle tcell.Style, softwrapped bool, maxLineNumLength int, vloc *Loc, bloc *Loc) {
+	lineNum := strconv.Itoa(bloc.Y + 1)
+
+	// Write the spaces before the line number if necessary
+	for i := 0; i < maxLineNumLength-len(lineNum); i++ {
+		screen.SetContent(w.X+vloc.X, w.Y+vloc.Y, ' ', nil, lineNumStyle)
+		vloc.X++
+	}
+	// Write the actual line number
+	for _, ch := range lineNum {
+		if softwrapped {
+			screen.SetContent(w.X+vloc.X, w.Y+vloc.Y, ' ', nil, lineNumStyle)
+		} else {
+			screen.SetContent(w.X+vloc.X, w.Y+vloc.Y, ch, nil, lineNumStyle)
+		}
+		vloc.X++
+	}
+
+	// Write the extra space
+	screen.SetContent(w.X+vloc.X, w.Y+vloc.Y, ' ', nil, lineNumStyle)
+	vloc.X++
+}
+
+// GetStyle returns the highlight style for the given character position
+// If there is no change to the current highlight style it just returns that
+func (w *Window) GetStyle(style tcell.Style, bloc Loc, r rune) tcell.Style {
+	if group, ok := w.Buf.Match(bloc.Y)[bloc.X]; ok {
+		s := GetColor(group.String())
+		return s
+	}
+	return style
+}
+
+// DisplayBuffer draws the buffer being shown in this window on the screen
+func (w *Window) DisplayBuffer() {
+	b := w.Buf
+
+	bufHeight := w.Height
+	if b.Settings["statusline"].(bool) {
+		bufHeight--
+	}
+
+	// TODO: Rehighlighting
+	// start := w.StartLine
+	if b.Settings["syntax"].(bool) && b.syntaxDef != nil {
+		// 	if start > 0 && b.lines[start-1].rehighlight {
+		// 		b.highlighter.ReHighlightLine(b, start-1)
+		// 		b.lines[start-1].rehighlight = false
+		// 	}
+		//
+		// 	b.highlighter.ReHighlightStates(b, start)
+		//
+		b.highlighter.HighlightMatches(b, w.StartLine, w.StartLine+bufHeight)
+	}
+
+	lineNumStyle := defStyle
+	if style, ok := colorscheme["line-number"]; ok {
+		lineNumStyle = style
+	}
+
+	// We need to know the string length of the largest line number
+	// so we can pad appropriately when displaying line numbers
+	maxLineNumLength := len(strconv.Itoa(len(b.lines)))
+
+	tabsize := int(b.Settings["tabsize"].(float64))
+	softwrap := b.Settings["softwrap"].(bool)
+
+	// this represents the current draw position
+	// within the current window
+	vloc := Loc{0, 0}
+
+	// this represents the current draw position in the buffer (char positions)
+	bloc := Loc{w.StartCol, w.StartLine}
+
+	curStyle := defStyle
+	for vloc.Y = 0; vloc.Y < bufHeight; vloc.Y++ {
+		vloc.X = 0
+		if b.Settings["ruler"].(bool) {
+			w.DrawLineNum(lineNumStyle, false, maxLineNumLength, &vloc, &bloc)
+		}
+
+		line := b.LineBytes(bloc.Y)
+		line, nColsBeforeStart := SliceVisualEnd(line, bloc.X, tabsize)
+		totalwidth := bloc.X - nColsBeforeStart
+		for len(line) > 0 {
+			r, size := utf8.DecodeRune(line)
+
+			curStyle = w.GetStyle(curStyle, bloc, r)
+
+			if nColsBeforeStart <= 0 {
+				screen.SetContent(w.X+vloc.X, w.Y+vloc.Y, r, nil, curStyle)
+				vloc.X++
+			}
+			nColsBeforeStart--
+
+			width := 0
+
+			char := ' '
+			switch r {
+			case '\t':
+				ts := tabsize - (totalwidth % tabsize)
+				width = ts
+			default:
+				width = runewidth.RuneWidth(r)
+				char = '@'
+			}
+
+			bloc.X++
+			line = line[size:]
+
+			// Draw any extra characters either spaces for tabs or @ for incomplete wide runes
+			if width > 1 {
+				for i := 1; i < width; i++ {
+					if nColsBeforeStart <= 0 {
+						screen.SetContent(w.X+vloc.X, w.Y+vloc.Y, char, nil, curStyle)
+						vloc.X++
+					}
+					nColsBeforeStart--
+				}
+			}
+			totalwidth += width
+
+			// If we reach the end of the window then we either stop or we wrap for softwrap
+			if vloc.X >= w.Width {
+				if !softwrap {
+					break
+				} else {
+					vloc.Y++
+					if vloc.Y >= bufHeight {
+						break
+					}
+					vloc.X = 0
+					// This will draw an empty line number because the current line is wrapped
+					w.DrawLineNum(lineNumStyle, true, maxLineNumLength, &vloc, &bloc)
+				}
+			}
+		}
+		bloc.X = w.StartCol
+		bloc.Y++
+		if bloc.Y >= len(b.lines) {
+			break
+		}
+	}
+}
+
+func (w *Window) DisplayStatusLine() {
+	w.sline.Display()
+}