Introduce a new config struct the lives above the raw disk implementation.

This should let us include values that would not be written to disk like the folder containing the config.

src/config/full.rs

@@ -0,0 +1,32 @@
+use std::path::PathBuf;
+use tokio::fs::File;
+use tokio::io::AsyncWriteExt;
+
+use super::raw::RawConfig;
+
+/// This is the config struct used by most of the code, which is an interpreted version of the RawConfig struct which is the raw disk-representation of the config.
+pub(crate) struct Config {
+    raw: RawConfig,
+    root_dir: PathBuf,
+}
+
+impl Config {
+    pub(crate) fn new<P: Into<PathBuf>>(root_dir: P) -> Result<Config, Box<dyn std::error::Error>> {
+        Ok(Config {
+            raw: RawConfig::default(),
+            root_dir: root_dir.into(),
+        })
+    }
+
+    pub(crate) async fn write_to_disk(&self) -> Result<(), Box<dyn std::error::Error>> {
+        let mut config_file = File::create(self.get_path_to_config_file()).await?;
+        config_file
+            .write_all(toml::to_string(&self.raw)?.as_bytes())
+            .await?;
+        Ok(())
+    }
+
+    pub(crate) fn get_path_to_config_file(&self) -> PathBuf {
+        self.root_dir.join("writer.toml")
+    }
+}

src/config/mod.rs

@@ -1,2 +1,3 @@
-mod definition;
-pub(crate) use definition::Config;
+mod full;
+mod raw;
+pub(crate) use full::Config;

src/config/raw.rs

@@ -3,15 +3,15 @@ use serde::Serialize;
 
 /// This is the struct for the writer.toml config file that ends up in each site's root directory.
 #[derive(Deserialize, Serialize)]
-pub(crate) struct Config {
+pub(crate) struct RawConfig {
     site_title: String,
     author: Option<String>,
     email: Option<String>,
 }
 
-impl Default for Config {
+impl Default for RawConfig {
     fn default() -> Self {
-        Config {
+        RawConfig {
             site_title: "My super awesome website".to_owned(),
             author: None,
             email: None,