From 78c87ab165d2a60c17778c68eb9932d6b1f6ce0c Mon Sep 17 00:00:00 2001
From: Achilleas Anagnostopoulos <achilleas.imap.mbox@gmail.com>
Date: Wed, 5 Jul 2017 15:52:45 +0100
Subject: [PATCH] Cleanup and revise TTY interface

---
 src/gopheros/device/tty/device.go     | 44 +++++++++++++++++++++++++++
 src/gopheros/kernel/driver/tty/tty.go | 19 ------------
 2 files changed, 44 insertions(+), 19 deletions(-)
 create mode 100644 src/gopheros/device/tty/device.go
 delete mode 100644 src/gopheros/kernel/driver/tty/tty.go

diff --git a/src/gopheros/device/tty/device.go b/src/gopheros/device/tty/device.go
new file mode 100644
index 0000000..a0f4e4d
--- /dev/null
+++ b/src/gopheros/device/tty/device.go
@@ -0,0 +1,44 @@
+package tty
+
+import (
+	"gopheros/device/video/console"
+	"io"
+)
+
+// State defines the supported terminal state values.
+type State uint8
+
+const (
+	// StateInactive marks the terminal as inactive. Any writes will be
+	// buffered and not synced to the attached console.
+	StateInactive State = iota
+
+	// StateActive marks the terminal as active. Any writes will be
+	// buffered and also synced to the attached console.
+	StateActive
+)
+
+// Device is implemented by objects that can be used as a terminal device.
+type Device interface {
+	io.Writer
+	io.ByteWriter
+
+	// AttachTo connects a TTY to a console instance.
+	AttachTo(console.Device)
+
+	// State returns the TTY's state.
+	State() State
+
+	// SetState updates the TTY's state.
+	SetState(State)
+
+	// CursorPosition returns the current cursor x,y coordinates. Both
+	// coordinates are 1-based (top-left corner has coordinates 1,1).
+	CursorPosition() (uint16, uint16)
+
+	// SetCursorPosition sets the current cursor position to (x,y). Both
+	// coordinates are 1-based (top-left corner has coordinates 1,1).
+	// Implementations are expected to clip the cursor position to their
+	// viewport.
+	SetCursorPosition(x, y uint16)
+}
diff --git a/src/gopheros/kernel/driver/tty/tty.go b/src/gopheros/kernel/driver/tty/tty.go
deleted file mode 100644
index f46ce2f..0000000
--- a/src/gopheros/kernel/driver/tty/tty.go
+++ /dev/null
@@ -1,19 +0,0 @@
-package tty
-
-import "io"
-
-// Tty is implemented by objects that can register themselves as ttys.
-type Tty interface {
-	io.Writer
-	io.ByteWriter
-
-	// Position returns the current cursor position (x, y).
-	Position() (uint16, uint16)
-
-	// SetPosition sets the current cursor position to (x,y). Console implementations
-	// must clip the provided cursor position if it exceeds the console dimensions.
-	SetPosition(x, y uint16)
-
-	// Clear clears the terminal.
-	Clear()
-}