From d5cc9708556191b7da3119c0398d05c9e5b2317d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Franti=C5=A1ek=20Boh=C3=A1=C4=8Dek?=
 <fandabohacek@gmail.com>
Date: Mon, 14 Jun 2021 21:37:50 +0200
Subject: [PATCH] feat: add basic image functions

---
 image-viewer/include/image.h | 56 +++++++++++++++++++++++++++++++++
 image-viewer/src/image.c     | 61 ++++++++++++++++++++++++++++++++++++
 2 files changed, 117 insertions(+)
 create mode 100644 image-viewer/include/image.h
 create mode 100644 image-viewer/src/image.c

diff --git a/image-viewer/include/image.h b/image-viewer/include/image.h
new file mode 100644
index 0000000..c7d1a8d
--- /dev/null
+++ b/image-viewer/include/image.h
@@ -0,0 +1,56 @@
+#ifndef __IMAGE_H__
+#define __IMAGE_H__
+
+#include <magic.h>
+#include <stdio.h>
+#include <jpeglib.h>
+#include <png.h>
+
+#include <stdbool.h>
+#include <stdint.h>
+
+#include "display_utils.h"
+
+typedef enum {
+  IMG_UNKNOWN,
+  IMG_PNG,
+  IMG_JPG,
+  IMG_PPM,
+} image_type_t;
+
+typedef enum {
+  IMERR_SUCCESS,
+  IMERR_UNKNOWN_FORMAT,
+  IMERR_FILE_NOT_FOUND,
+  IMERR_FILE_NO_PERMISSIONS,
+  IMERR_FILE_CANT_OPEN,
+  IMERR_WRONG_FORMAT,
+  IMERR_UNKNOWN,
+} image_error_t;
+
+typedef struct {
+  char *path;
+  image_type_t type;
+
+  display_pixel_t *pixels;
+
+  uint16_t width;
+  uint16_t height;
+} image_t;
+
+typedef struct {
+  uint16_t x;
+  uint16_t y;
+
+  uint16_t width;
+  uint16_t height;
+} image_region_t;
+
+image_t image_create(char *path);
+void image_destroy(image_t *image);
+
+image_region_t image_region_create(uint16_t x, uint16_t y, uint16_t width, uint16_t height);
+
+bool image_write_to_display(image_t *image, display_t *display, image_region_t region);
+
+#endif // __IMAGE_H__
diff --git a/image-viewer/src/image.c b/image-viewer/src/image.c
new file mode 100644
index 0000000..792b768
--- /dev/null
+++ b/image-viewer/src/image.c
@@ -0,0 +1,61 @@
+#include "image.h"
+#include <stdlib.h>
+
+image_t image_create(char *path) {
+  image_t image = {
+    .path = path,
+    .width = 0,
+    .height = 0,
+    .pixels = NULL,
+    .type = IMG_UNKNOWN,
+  };
+
+  return image;
+}
+
+void image_destroy(image_t *image) {
+  if (image->pixels == NULL) {
+    free(image->pixels);
+  }
+}
+
+image_region_t image_region_create(uint16_t x, uint16_t y, uint16_t width,
+                                   uint16_t height) {
+  image_region_t region = {
+    .x = x,
+    .y = y,
+    .width = width,
+    .height = height,
+  };
+
+  return region;
+}
+
+double get_scale_factor(uint16_t w, uint16_t h, image_region_t display_region) {
+  double scale_x = (double)display_region.width / (double)w;
+  double scale_y = (double)display_region.height / (double)h;
+
+  double max = scale_x > scale_y ? scale_x : scale_y;
+  double min = scale_x <= scale_y ? scale_x : scale_y;
+  double scale = max;
+
+  if (w * max > display_region.width || h * max > display_region.height) {
+    scale = min;
+  }
+
+  return scale;
+}
+
+bool image_write_to_display(image_t *image, display_t *display,
+                            image_region_t region) {
+  uint16_t w = region.width, h = region.height;
+  uint16_t x = region.x, y = region.y;
+
+  image_region_t display_region = image_region_create(0, 0, DISPLAY_WIDTH, DISPLAY_HEIGHT);
+  double scale = get_scale_factor(w, h, display_region);
+
+  uint16_t sw = (uint16_t)(scale * w), sh = (uint16_t)(scale * h);
+
+  // scaling
+  return true;
+}
-- 
2.48.1