From 91277afef6904c7c8270e2a60d4190e9c35453f7 Mon Sep 17 00:00:00 2001
From: fvanroie <15969459+fvanroie@users.noreply.github.com>
Date: Wed, 2 Feb 2022 08:07:44 +0100
Subject: [PATCH] Fix screenshot issue on macOS / iOS / Safari

---
 src/hasp_gui.cpp          | 52 ++++++++++++++++++++++++++++++---------
 src/hasp_gui.h            | 21 ++++++++++++++++
 src/sys/svc/hasp_http.cpp |  2 +-
 3 files changed, 63 insertions(+), 12 deletions(-)

diff --git a/src/hasp_gui.cpp b/src/hasp_gui.cpp
index 8e40b9ba..1bec7091 100644
--- a/src/hasp_gui.cpp
+++ b/src/hasp_gui.cpp
@@ -545,10 +545,8 @@ bool guiSetConfig(const JsonObject& settings)
     changed |= configSet(gui_settings.backlight_pin, settings[FPSTR(FP_GUI_BACKLIGHTPIN)], F("guiBacklightPin"));
     changed |= configSet(guiSleepTime1, settings[FPSTR(FP_GUI_IDLEPERIOD1)], F("guiSleepTime1"));
     changed |= configSet(guiSleepTime2, settings[FPSTR(FP_GUI_IDLEPERIOD2)], F("guiSleepTime2"));
-    changed |=
-        configSet(gui_settings.rotation, settings[FPSTR(FP_GUI_ROTATION)], F("gui_settings.rotation"));
-    changed |=
-        configSet(gui_settings.invert_display, settings[FPSTR(FP_GUI_INVERT)], F("guiInvertDisplay"));
+    changed |= configSet(gui_settings.rotation, settings[FPSTR(FP_GUI_ROTATION)], F("gui_settings.rotation"));
+    changed |= configSet(gui_settings.invert_display, settings[FPSTR(FP_GUI_INVERT)], F("guiInvertDisplay"));
 
     hasp_set_sleep_time(guiSleepTime1, guiSleepTime2);
 
@@ -617,11 +615,42 @@ static void guiSetBmpHeader(uint8_t* buffer_p, int32_t data)
  **/
 static void gui_get_bitmap_header(uint8_t* buffer, size_t bufsize)
 {
-    memset(buffer, 0, bufsize);
-
     lv_disp_t* disp = lv_disp_get_default();
-    buffer[0]       = 0x42; // B
-    buffer[1]       = 0x4D; // M
+
+    // memset(buffer, 0, bufsize);
+    char* bm = "BM";
+    memcpy(buffer, bm, strlen(bm));
+    buffer += strlen(bm);
+
+    bmp_header_t* bmp = (bmp_header_t*)buffer;
+    bmp->bfSize       = (uint32_t)(disp->driver.hor_res * disp->driver.ver_res * LV_COLOR_DEPTH / 8);
+    bmp->bfReserved   = 0;
+    bmp->bfOffBits    = 66;
+
+    bmp->biSize          = 40;
+    bmp->biWidth         = disp->driver.hor_res;
+    bmp->biHeight        = -disp->driver.ver_res;
+    bmp->biPlanes        = 1;
+    bmp->biBitCount      = LV_COLOR_DEPTH;
+    bmp->biCompression   = 3; // BI_BITFIELDS
+    bmp->biSizeImage     = bmp->bfSize;
+    bmp->biXPelsPerMeter = 2836;
+    bmp->biYPelsPerMeter = 2836;
+    bmp->biClrUsed       = 0;
+    bmp->biClrImportant  = 0;
+
+    // R: 1111 1000 | 0000 0000
+    bmp->bdMask[0] = 0xF800; // Red bitmask
+                             // G: 0000 0111 | 1110 0000
+    bmp->bdMask[1] = 0x07E0; // Green bitmask
+                             // B: 0000 0000 | 0001 1111
+    bmp->bdMask[2] = 0x001F; // Blue bitmask
+
+/*
+    return;
+    // lv_disp_t* disp = lv_disp_get_default();
+    buffer[0] = 0x42; // B
+    buffer[1] = 0x4D; // M
 
     buffer[10 + 0] = 122;      // full header size
     buffer[14 + 0] = 122 - 14; // dib header size
@@ -662,6 +691,7 @@ static void gui_get_bitmap_header(uint8_t* buffer, size_t bufsize)
     buffer[70 + 2] = 0x69;
     buffer[70 + 1] = 0x6E;
     buffer[70 + 0] = 0x20;
+    */
 }
 
 void gui_flush_not_complete()
@@ -701,8 +731,8 @@ void guiTakeScreenshot(const char* pFileName)
     pFileOut = HASP_FS.open(pFileName, "w");
     if(pFileOut) {
 
-        size_t len = pFileOut.write(buffer, 122);
-        if(len == 122) {
+        size_t len = pFileOut.write(buffer, 66);
+        if(len == 66) {
             LOG_VERBOSE(TAG_GUI, F("Bitmap header written"));
 
             /* Refresh screen to screenshot callback */
@@ -754,7 +784,7 @@ void guiTakeScreenshot()
     uint8_t buffer[128];
     gui_get_bitmap_header(buffer, sizeof(buffer));
 
-    if(httpClientWrite(buffer, 122) == 122) {
+    if(httpClientWrite(buffer, 66) == 66) { // 122
         LOG_VERBOSE(TAG_GUI, F("Bitmap header sent"));
 
         /* Refresh screen to screenshot callback */
diff --git a/src/hasp_gui.h b/src/hasp_gui.h
index 6ae4a90a..ac13077c 100644
--- a/src/hasp_gui.h
+++ b/src/hasp_gui.h
@@ -6,6 +6,27 @@
 
 #include "hasplib.h"
 
+struct bmp_header_t
+{
+    uint32_t bfSize;
+    uint32_t bfReserved;
+    uint32_t bfOffBits;
+
+    uint32_t biSize;
+    int32_t biWidth;
+    int32_t biHeight;
+    uint16_t biPlanes;
+    uint16_t biBitCount;
+    uint32_t biCompression;
+    uint32_t biSizeImage;
+    int32_t biXPelsPerMeter;
+    int32_t biYPelsPerMeter;
+    uint32_t biClrUsed;
+    uint32_t biClrImportant;
+
+    uint32_t bdMask[3];
+};
+
 struct gui_conf_t
 {
     bool show_pointer;
diff --git a/src/sys/svc/hasp_http.cpp b/src/sys/svc/hasp_http.cpp
index 14038270..a07c1dbe 100644
--- a/src/sys/svc/hasp_http.cpp
+++ b/src/sys/svc/hasp_http.cpp
@@ -429,7 +429,7 @@ static void webHandleScreenshot()
 
         if(webServer.hasArg(F("q"))) {
             lv_disp_t* disp = lv_disp_get_default();
-            webServer.setContentLength(122 + disp->driver.hor_res * disp->driver.ver_res * sizeof(lv_color_t));
+            webServer.setContentLength(66 + disp->driver.hor_res * disp->driver.ver_res * sizeof(lv_color_t));
             webServer.send_P(200, PSTR("image/bmp"), "");
             guiTakeScreenshot();
             webServer.client().stop();