From 6642cc6506a6f36c5a46dee350adab103adb8033 Mon Sep 17 00:00:00 2001
From: Cheney <me@chenye.org>
Date: Mon, 21 Sep 2015 13:13:30 +0800
Subject: [PATCH] support history

---
 .gitignore  |  2 ++
 history.go  | 56 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 readline.go | 34 +++++++++++++++++++++++++-------
 runebuf.go  | 11 +++++++++--
 terminal.go |  5 ++---
 utils.go    |  2 ++
 6 files changed, 98 insertions(+), 12 deletions(-)
 create mode 100644 .gitignore
 create mode 100644 history.go

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..d4dc10f
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,2 @@
+
+*.tmp
diff --git a/history.go b/history.go
new file mode 100644
index 0000000..a58c89a
--- /dev/null
+++ b/history.go
@@ -0,0 +1,56 @@
+package readline
+
+func (l *Readline) PrevHistory() []rune {
+	if l.current == nil {
+		return nil
+	}
+	current := l.current.Prev()
+	if current == nil {
+		return nil
+	}
+	l.current = current
+	return current.Value.([]rune)
+}
+
+func (l *Readline) NextHistory() []rune {
+	if l.current == nil {
+		return nil
+	}
+	current := l.current.Next()
+	if current == nil {
+		return nil
+	}
+	l.current = current
+	return current.Value.([]rune)
+}
+
+func (l *Readline) NewHistory(current []rune) {
+	l.UpdateHistory(current)
+	if l.current != l.history.Back() {
+		// move history item to current command
+		l.history.Remove(l.current)
+		use := l.current.Value.([]rune)
+		l.current = l.history.Back()
+		l.UpdateHistory(use)
+	}
+
+	// push a new one to commit current command
+	l.PushHistory(nil)
+}
+
+func (l *Readline) UpdateHistory(s []rune) {
+	if l.current == nil {
+		l.PushHistory(s)
+		return
+	}
+	r := l.current.Value.([]rune)
+	l.current.Value = append(r[:0], s...)
+}
+
+func (l *Readline) PushHistory(s []rune) {
+	// copy
+	newCopy := make([]rune, len(s))
+	copy(newCopy, s)
+	elem := l.history.PushBack(newCopy)
+	l.current = elem
+}
diff --git a/readline.go b/readline.go
index 342643e..63c0521 100644
--- a/readline.go
+++ b/readline.go
@@ -1,6 +1,7 @@
 package readline
 
 import (
+	"container/list"
 	"io"
 	"os"
 )
@@ -10,15 +11,21 @@ type Readline struct {
 	t       *Terminal
 	buf     *RuneBuffer
 	outchan chan []rune
+
+	history *list.List
+	current *list.Element
 }
 
 const (
 	CharLineStart = 0x1
 	CharLineEnd   = 0x5
-	CharPrev      = 0x2
-	CharNext      = 0x6
+	CharNext      = 0xe
+	CharPrev      = 0x10
+	CharBackward  = 0x2
+	CharForward   = 0x6
 	CharEscape    = 0x7f
 	CharEnter     = 0xd
+	CharEnter2    = 0xa
 )
 
 type wrapWriter struct {
@@ -40,6 +47,7 @@ func newReadline(r *os.File, t *Terminal, prompt string) *Readline {
 		t:       t,
 		buf:     NewRuneBuffer(t, prompt),
 		outchan: make(chan []rune),
+		history: list.New(),
 	}
 	go rl.ioloop()
 	return rl
@@ -63,21 +71,33 @@ func (l *Readline) ioloop() {
 			l.buf.Delete()
 		case CharEscape:
 			l.buf.BackEscape()
-		case CharEnter:
+		case CharEnter, CharEnter2:
 			l.buf.WriteRune('\n')
 			data := l.buf.Reset()
-			l.outchan <- data[:len(data)-1]
+			data = data[:len(data)-1] // trim \n
+			l.outchan <- data
+			l.NewHistory(data)
+		case CharBackward:
+			l.buf.MoveBackward()
+		case CharForward:
+			l.buf.MoveForward()
 		case CharPrev:
-			l.buf.MovePrev()
+			buf := l.PrevHistory()
+			if buf != nil {
+				l.buf.Set(buf)
+			}
 		case CharNext:
-			l.buf.MoveNext()
+			buf := l.NextHistory()
+			if buf != nil {
+				l.buf.Set(buf)
+			}
 		case KeyInterrupt:
 			l.buf.WriteString("^C\n")
 			l.outchan <- nil
-			break
 		default:
 			l.buf.WriteRune(r)
 		}
+		l.UpdateHistory(l.buf.Runes())
 	}
 }
 
diff --git a/runebuf.go b/runebuf.go
index 33348d4..a1d82be 100644
--- a/runebuf.go
+++ b/runebuf.go
@@ -42,7 +42,7 @@ func (r *RuneBuffer) MoveToLineStart() {
 	r.Refresh(-1, r.SetIdx(0))
 }
 
-func (r *RuneBuffer) MovePrev() {
+func (r *RuneBuffer) MoveBackward() {
 	if r.idx == 0 {
 		return
 	}
@@ -65,7 +65,7 @@ func (rb *RuneBuffer) WriteRunes(r []rune) {
 	rb.Refresh(1, 1)
 }
 
-func (r *RuneBuffer) MoveNext() {
+func (r *RuneBuffer) MoveForward() {
 	if r.idx == len(r.buf) {
 		return
 	}
@@ -187,3 +187,10 @@ func (r *RuneBuffer) Reset() []rune {
 	r.Refresh(-len(ret), r.SetIdx(0))
 	return ret
 }
+
+func (r *RuneBuffer) Set(buf []rune) {
+	length, idx := len(r.buf), r.idx
+	r.buf = buf
+	r.idx = len(r.buf)
+	r.RefreshSet(length, idx)
+}
diff --git a/terminal.go b/terminal.go
index de78782..ef5bc6e 100644
--- a/terminal.go
+++ b/terminal.go
@@ -21,7 +21,6 @@ const (
 	KeyInterrupt = 0x3
 	KeyNextChar  = 0x6
 	KeyDelete    = 0x4
-	KeyEnter     = 0xd
 	KeyEsc       = 0x1b
 )
 
@@ -89,9 +88,9 @@ func (t *Terminal) ioloop() {
 			goto exit
 		case KeyEsc:
 			prefix = true
-		case KeyEnter, KeyPrevChar, KeyNextChar, KeyDelete:
+		case CharEnter, CharEnter2, KeyPrevChar, KeyNextChar, KeyDelete:
 			fallthrough
-		case CharLineEnd, CharLineStart:
+		case CharLineEnd, CharLineStart, CharNext, CharPrev:
 			t.outchan <- r
 		default:
 			println("np:", r)
diff --git a/utils.go b/utils.go
index cfbc5b0..cc4752a 100644
--- a/utils.go
+++ b/utils.go
@@ -33,6 +33,8 @@ func prefixKey(r rune) rune {
 		r = MetaNext
 	case 'd':
 		r = MetaDelete
+	case KeyEsc:
+
 	}
 	return r
 }