Break stuff

editor/constants.go

@@ -0,0 +1,7 @@
+package editor
+
+// ----------------------------------------------------------------------------
+// !Constants
+// ----------------------------------------------------------------------------
+
+const KiloVersion = "0.0.1"

editor/editor.go

@@ -2,12 +2,11 @@ package editor
 
 import (
 	"fmt"
+	"strings"
 	"timshome.page/gilo/fn"
 	"timshome.page/gilo/terminal"
 )
 
-const KiloVersion = "0.0.1"
-
 // ----------------------------------------------------------------------------
 // !Editor
 // ----------------------------------------------------------------------------
@@ -43,26 +42,6 @@ func (e *editor) RefreshScreen() {
 	terminal.Write(ab.toString())
 }
 
-func (e *editor) ProcessKeypress() bool {
-	ch, _ := terminal.ReadKey()
-
-	// Clean up on exit
-	if ch == fn.Ctrl('q') {
-		terminal.Write(terminal.ClearScreen + terminal.ResetCursor)
-
-		return false
-	}
-
-	switch ch {
-	case 'w', 'a', 's', 'd':
-		e.moveCursor(ch)
-	default:
-		// Do nothing!
-	}
-
-	return true
-}
-
 func (e *editor) drawRows(ab *buffer) {
 	for y :=0; y < e.screen.Rows; y += 1 {
 		if y == e.screen.Rows / 3 {
@@ -95,15 +74,44 @@ func (e *editor) drawRows(ab *buffer) {
 	}
 }
 
-func (e *editor) moveCursor (key rune) {
+func (e *editor) ProcessKeypress() bool {
+	str, _ := terminal.Read()
+
+	// Escape sequences can be less fun...
+	if strings.Contains(str, terminal.EscPrefix) {
+		code := strings.TrimPrefix(str, terminal.EscPrefix)
+
+		switch code {
+		case KeyArrowUp, KeyArrowDown, KeyArrowLeft, KeyArrowRight:
+			e.moveCursor(code)
+		default:
+			// Do something later
+		}
+	}
+
+	for _, ch := range str {
+		// Clean up on exit
+		if ch == fn.Ctrl('q') {
+			terminal.Write(terminal.ClearScreen + terminal.ResetCursor)
+
+			return false
+		}
+	}
+
+	return true
+}
+
+func (e *editor) moveCursor (rawKey string) {
+	key := keyMap[rawKey]
+
 	switch key {
-	case 'a':
+	case keyLeft:
 		e.cursor.x -= 1
-	case 'd':
+	case keyRight:
 		e.cursor.x += 1
-	case 'w':
+	case keyUp:
 		e.cursor.y -= 1
-	case 's':
+	case keyDown:
 		e.cursor.y += 1
 	}
 }

editor/keymap.go

@@ -0,0 +1,30 @@
+package editor
+
+// ----------------------------------------------------------------------------
+// !Terminal Input Escape Code Sequences
+// ----------------------------------------------------------------------------
+
+const(
+	KeyArrowUp = "A"
+	KeyArrowDown = "B"
+	KeyArrowRight = "C"
+	KeyArrowLeft = "D"
+)
+
+// ----------------------------------------------------------------------------
+// !Map escape sequences to simpler constants
+// ----------------------------------------------------------------------------
+
+const (
+	keyUp = "ARROW_UP"
+	keyDown = "ARROW_DOWN"
+	keyLeft = "ARROW_LEFT"
+	keyRight = "ARROW_RIGHT"
+)
+
+var keyMap = map[string]string{
+	KeyArrowUp: keyUp,
+	KeyArrowDown: keyDown,
+	KeyArrowLeft: keyLeft,
+	KeyArrowRight: keyRight,
+}

terminal/ansi.go

@@ -3,24 +3,44 @@ package terminal
 
 import "fmt"
 
-const ClearLine = "\x1b[K"
-const ClearScreen = "\x1b[2J"
+// ----------------------------------------------------------------------------
+// !Terminal Escape Code Sequences
+// ----------------------------------------------------------------------------
 
-const HideCursor = "\x1b[?25l"
-const ShowCursor = "\x1b[?25h"
-const ResetCursor = "\x1b[H"
+const EscPrefix = "\x1b["
 
-const KeyArrowUp = "\x1b[A"
-const KeyArrowDown = "\x1b[B"
-const KeyArrowRight = "\x1b[C"
-const KeyArrowLeft = "\x1b[D"
 
+const (
+	// Clears the line after the escape sequence
+	ClearLine = "\x1b[K"
+
+	// Clears the entire screen
+	ClearScreen = "\x1b[2J"
+)
+
+// Cursor Codes
+const (
+	HideCursor = "\x1b[?25l"
+	ShowCursor = "\x1b[?25h"
+
+	// Reports cursor location to stdout
+	LocateCursor = "\x1b[6n"
+
+	// Moves cursor to default position (1,1)
+	ResetCursor = "\x1b[H"
+)
+
+// ----------------------------------------------------------------------------
+// !Helpers
+// ----------------------------------------------------------------------------
+
+// Add the ANSI escape code prefix to the relevant escape code
 func Code (s string) string {
-	return fmt.Sprintf("\x1b[%s", s)
+	return fmt.Sprintf("%s%s", EscPrefix, s)
 }
 
 
-// Move the terminal cursor to the 0-based coordinate
+// Generate the escape sequence to move the terminal cursor to the 0-based coordinate
 func MoveCursor(x int, y int) string {
 	// Allow 0-based indexing, the terminal code is 1-based
 	x += 1

terminal/size.go

@@ -33,10 +33,10 @@ func Size () *Screen {
 func sizeTrick () (rows int, cols int) {
 	// Move cursor to location further than likely screen size
 	// The cursor will move to maximum available position
-	fmt.Print("\x1b[999C\x1b[99B")
+	fmt.Print(Code("999C") + Code("999B"))
 
 	// Ask the terminal where the cursor is
-	fmt.Print("\x1b[6n")
+	fmt.Print(LocateCursor)
 
 	// Read stdin looking for the reported location
 	buffer := ""