From 14994a3f31aa0dcd1475967442236befe618fece Mon Sep 17 00:00:00 2001
From: Ayke van Laethem <aykevanlaethem@gmail.com>
Date: Mon, 6 Nov 2023 18:17:51 +0100
Subject: [PATCH] epd2in13: unify rotation configuration with other displays

This commit updates rotation behavior to match other displays.
For more information, see: https://github.com/tinygo-org/drivers/pull/550

This changes the signature of `SetRotation` but I don't think any
existing code will be affected by this change.
---
 waveshare-epd/epd2in13/epd2in13.go  | 35 +++++++++++++++++------------
 waveshare-epd/epd2in13/registers.go | 10 +++++----
 2 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/waveshare-epd/epd2in13/epd2in13.go b/waveshare-epd/epd2in13/epd2in13.go
index c0d190f..bc289ad 100644
--- a/waveshare-epd/epd2in13/epd2in13.go
+++ b/waveshare-epd/epd2in13/epd2in13.go
@@ -15,8 +15,8 @@ import (
 type Config struct {
 	Width        int16 // Width is the display resolution
 	Height       int16
-	LogicalWidth int16    // LogicalWidth must be a multiple of 8 and same size or bigger than Width
-	Rotation     Rotation // Rotation is clock-wise
+	LogicalWidth int16 // LogicalWidth must be a multiple of 8 and same size or bigger than Width
+	Rotation     drivers.Rotation
 }
 
 type Device struct {
@@ -30,10 +30,11 @@ type Device struct {
 	height       int16
 	buffer       []uint8
 	bufferLength uint32
-	rotation     Rotation
+	rotation     drivers.Rotation
 }
 
-type Rotation uint8
+// Deprecated: use drivers.Rotation instead.
+type Rotation = drivers.Rotation
 
 // Look up table for full updates
 var lutFullUpdate = [30]uint8{
@@ -209,13 +210,13 @@ func (d *Device) DisplayRect(x int16, y int16, width int16, height int16) error
 	if x < 0 || y < 0 || x >= d.logicalWidth || y >= d.height || width < 0 || height < 0 {
 		return errors.New("wrong rectangle")
 	}
-	if d.rotation == ROTATION_90 {
+	if d.rotation == drivers.Rotation90 {
 		width, height = height, width
 		x -= width
-	} else if d.rotation == ROTATION_180 {
+	} else if d.rotation == drivers.Rotation180 {
 		x -= width - 1
 		y -= height - 1
-	} else if d.rotation == ROTATION_270 {
+	} else if d.rotation == drivers.Rotation270 {
 		width, height = height, width
 		y -= height
 	}
@@ -301,27 +302,33 @@ func (d *Device) ClearBuffer() {
 
 // Size returns the current size of the display.
 func (d *Device) Size() (w, h int16) {
-	if d.rotation == ROTATION_90 || d.rotation == ROTATION_270 {
+	if d.rotation == drivers.Rotation90 || d.rotation == drivers.Rotation270 {
 		return d.height, d.logicalWidth
 	}
 	return d.logicalWidth, d.height
 }
 
-// SetRotation changes the rotation (clock-wise) of the device
-func (d *Device) SetRotation(rotation Rotation) {
+// Rotation returns the current rotation of the device.
+func (d *Device) Rotation() drivers.Rotation {
+	return d.rotation
+}
+
+// SetRotation changes the rotation of the device.
+func (d *Device) SetRotation(rotation drivers.Rotation) error {
 	d.rotation = rotation
+	return nil
 }
 
 // xy chages the coordinates according to the rotation
 func (d *Device) xy(x, y int16) (int16, int16) {
 	switch d.rotation {
-	case NO_ROTATION:
+	case drivers.Rotation0:
 		return x, y
-	case ROTATION_90:
+	case drivers.Rotation90:
 		return d.width - y - 1, x
-	case ROTATION_180:
+	case drivers.Rotation180:
 		return d.width - x - 1, d.height - y - 1
-	case ROTATION_270:
+	case drivers.Rotation270:
 		return y, d.height - x - 1
 	}
 	return x, y
diff --git a/waveshare-epd/epd2in13/registers.go b/waveshare-epd/epd2in13/registers.go
index b5ee2e7..4ebd0da 100644
--- a/waveshare-epd/epd2in13/registers.go
+++ b/waveshare-epd/epd2in13/registers.go
@@ -1,5 +1,7 @@
 package epd2in13
 
+import "tinygo.org/x/drivers"
+
 // Registers
 const (
 	DRIVER_OUTPUT_CONTROL                = 0x01
@@ -24,8 +26,8 @@ const (
 	SET_RAM_Y_ADDRESS_COUNTER            = 0x4F
 	TERMINATE_FRAME_READ_WRITE           = 0xFF
 
-	NO_ROTATION  Rotation = 0
-	ROTATION_90  Rotation = 1 // 90 degrees clock-wise rotation
-	ROTATION_180 Rotation = 2
-	ROTATION_270 Rotation = 3
+	NO_ROTATION  = drivers.Rotation0
+	ROTATION_90  = drivers.Rotation90 // 90 degrees clock-wise rotation
+	ROTATION_180 = drivers.Rotation180
+	ROTATION_270 = drivers.Rotation270
 )