gilo/internal/editor/editor.go

// The main interface/implementation of the editor object
package editor

import (
	"fmt"
	"time"
	doc "timshome.page/gilo/internal/editor/document"
	"timshome.page/gilo/internal/gilo"
	"timshome.page/gilo/internal/terminal"
)

// ----------------------------------------------------------------------------
// !Editor
// ----------------------------------------------------------------------------

type statusMsg struct {
	message string
	created time.Time
}

type editor struct {
	screen    *terminal.Screen
	cursor    *gilo.Point
	offset    *gilo.Point
	document  *doc.Document
	status    *statusMsg
	quitTimes uint8
	renderX   int
}

func NewEditor() *editor {
	screen := terminal.Size()

	// Subtract rows for status bar and message bar/prompt
	screen.Rows -= 2

	cursor := gilo.DefaultPoint()
	offset := gilo.DefaultPoint()
	document := doc.NewDocument()
	status := &statusMsg{
		"",
		time.Now(),
	}

	return &editor{
		screen,
		cursor,
		offset,
		document,
		status,
		gilo.QuitTimes,
		0,
	}
}

func (e *editor) Open(filename string) {
	e.document.Open(filename)
}

func (e *editor) Save() {
	size := e.document.Save()

	if size > 0 {
		e.SetStatusMessage("%d bytes written to disk", size)
	} else {
		e.SetStatusMessage("Failed to save file")
	}
}

func (e *editor) SetStatusMessage(template string, a ...interface{}) {
	e.status = &statusMsg{
		fmt.Sprintf(template, a...),
		time.Now(),
	}
}

func (e *editor) ProcessKeypress() bool {
	ch, _ := terminal.ReadKey()

	return e.processKeypressChar(ch)
}

func (e *editor) insertChar(ch rune) {
	if e.cursor.Y == e.document.RowCount() {
		e.document.AppendRow("")
	}

	e.document.InsertChar(e.cursor, ch)
	e.cursor.X += 1
}

func (e *editor) delChar() {
	if e.cursor.Y == e.document.RowCount() {
		return
	}

	if e.cursor.X == 0 && e.cursor.Y == 0 {
		return
	}

	if e.cursor.X > 0 {
		at := e.cursor
		at.X -= 1
		e.document.DelChar(at)

		e.cursor.X -= 1
	} else {
		// Move cursor to the current end of the previous line
		e.cursor.X = e.document.Row(e.cursor.Y - 1).Size()

		// Move the contents of the current row to the previous
		e.document.MergeRows(e.cursor.Y - 1, e.cursor.Y)

		e.cursor.Y -= 1
	}
}