Load config file

- Read image file path from config file.
- "mode" left untouched for now.

Cargo.toml

@@ -8,6 +8,7 @@ anyhow = "1.0.100"
 dirs = "6.0.0"
 image = { version = "0.25.9", default-features = false, features = ["png", "jpeg"] }
 pico-args = "0.5.0"
+serde = { version = "1.0.228", default-features = false, features = ["derive"] }
 toml = "0.9.8"
 x11rb = { version = "0.13.2", default-features = false }
 
@@ -16,4 +17,4 @@ lto = "thin"
 codegen-units = 1
 strip = "symbols"
 opt-level = "z"
-panic = "abort"
+panic = "abort"

src/config.rs

@@ -0,0 +1,36 @@
+use anyhow::{Context, Result};
+use serde::Deserialize;
+use std::fs;
+use std::path::PathBuf;
+
+/// Runtime configuration for `icing`.
+#[derive(Debug, Deserialize)]
+pub struct Config {
+    pub background_image: String,
+    pub mode: Option<String>, // Unused now, deal with it later
+}
+
+impl Config {
+    /// Load config from config file.
+    pub fn load() -> Result<Self> {
+        let path = config_path()?;
+
+        let contents = fs::read_to_string(&path)
+            .with_context(|| format!("Failed to read config file: {}", path.display()))?;
+
+        let config: Config = toml::from_str(&contents)
+            .with_context(|| format!("Failed to parse config file: {}", path.display()))?;
+
+        Ok(config)
+    }
+}
+
+fn config_path() -> Result<PathBuf> {
+    let mut path = dirs::config_dir().context("Could not determine XDG config directory")?; // Usually `~/.config/`
+    // `~/.config/candywidgets/icing/config.toml`
+    path.push("candywidgets");
+    path.push("icing");
+    path.push("config.toml");
+
+    Ok(path)
+}

src/main.rs

@@ -10,11 +10,13 @@ use x11rb::{
     },
     rust_connection::RustConnection,
 };
+mod config;
 
 fn main() -> Result<()> {
-    // Path to wallpaper image.
-    // This is hardcoded for now and will later be replaced by config loading.
-    let image_path = "/path/to/image";
+    // Load config
+    let config = config::Config::load()?;
+    // Path to wallpaper image in config
+    let image_path = &config.background_image;
 
     // Connect to the running graphical session, the X11 server.
     let (conn, screen_num) = RustConnection::connect(None)?;