[feat] support RGBA values as background color

generator/src/color.rs

@@ -13,9 +13,15 @@ impl Into<RgbaColor> for String {
             .chunks(2)
             .map(|chunk| i64::from_str_radix(&chunk.iter().collect::<String>(), 16).unwrap())
             .collect::<Vec<_>>();
+        
+        let alpha: i64;
+        match splits.get(3) {
+            Some(x) => alpha = *x,
+            None => alpha = 255,
+        }
 
         RgbaColor {
-            color: Color::from_rgba8(splits[0] as u8, splits[1] as u8, splits[2] as u8, 255),
+            color: Color::from_rgba8(splits[0] as u8, splits[1] as u8, splits[2] as u8, alpha as u8),
         }
     }
 }

generator/src/components/background.rs

@@ -11,6 +11,7 @@ use super::interface::{
 };
 
 const HEX_COLOR_LENGTH: usize = 7;
+const HEX_COLOR_WITH_ALPHA_LENGTH: usize = 9;
 
 pub struct Background {
     children: Vec<Box<dyn Component>>,
@@ -22,6 +23,11 @@ impl Background {
     }
 }
 
+fn is_valid_hex_color(color: String) -> bool {
+    (color.len() == HEX_COLOR_LENGTH || color.len() == HEX_COLOR_WITH_ALPHA_LENGTH)
+        && color.starts_with("#")
+}
+
 impl Component for Background {
     fn children(&self) -> &Vec<Box<dyn Component>> {
         &self.children
@@ -46,7 +52,7 @@ impl Component for Background {
         paint.anti_alias = false;
         match params.bg_color.as_ref() {
             Some(color) => {
-                if color.len() != HEX_COLOR_LENGTH || !color.starts_with("#") {
+                if ! is_valid_hex_color(color.to_string()){
                     return Err(RenderError::InvalidHexColor(color.to_string()));
                 }