add SDK config support

src/config.rs

@@ -0,0 +1,46 @@
+use std::collections::HashMap;
+use std::path::PathBuf;
+use std::str::FromStr;
+use super::Error;
+
+pub const CFG_DIR: &'static str = ".Playdate";
+pub const CFG_FILENAME: &'static str = "config";
+pub const CFG_KEY_SDK_ROOT: &'static str = "SDKRoot";
+
+pub struct SdkCfg(HashMap<String, String>);
+
+impl FromStr for SdkCfg {
+    type Err = Error;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        Ok(Self(
+            s.trim()
+                .lines()
+                .filter_map(|line| {
+                    line.split_once("\t")
+                        .map(|(k, v)| (k.to_owned(), v.to_owned()))
+                })
+                .collect(),
+        ))
+    }
+}
+
+impl SdkCfg {
+    pub fn sdk_path(&self) -> Option<PathBuf> {
+        self.0.get(CFG_KEY_SDK_ROOT).map(PathBuf::from)
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn parse() {
+        let path = "/path/PlaydateSDK-dir";
+        let cfg: SdkCfg = format!("{k}\t{v}\n", k = CFG_KEY_SDK_ROOT, v = path)
+            .parse()
+            .unwrap();
+        assert_eq!(cfg.sdk_path(), Some(PathBuf::from(path)));
+    }
+}

src/main.rs

@@ -1,6 +1,6 @@
 use anyhow::{anyhow, bail, Error};
 use inflector::cases::titlecase::to_title_case;
-use log::{info, debug};
+use log::{debug, info};
 use serde_derive::Deserialize;
 use std::{
     env,
@@ -16,6 +16,8 @@ use zip_extensions::zip_create_from_directory_with_options;
 #[cfg(unix)]
 use anyhow::Context;
 
+mod config;
+
 #[cfg(unix)]
 const GCC_PATH_STR: &'static str = "/usr/local/bin/arm-none-eabi-gcc";
 #[cfg(windows)]
@@ -44,7 +46,28 @@ const SDK_DIR: &'static str = "Developer";
 #[cfg(windows)]
 const SDK_DIR: &'static str = "Documents";
 
+fn playdate_sdk_cfg() -> Result<config::SdkCfg, Error> {
+    let cfg_path = dirs::home_dir()
+        .ok_or(anyhow!("Can't find home dir"))?
+        .join(config::CFG_DIR)
+        .join(config::CFG_FILENAME);
+    fs::read_to_string(cfg_path)?.parse()
+}
+
 fn playdate_sdk_path() -> Result<PathBuf, Error> {
+    match playdate_sdk_cfg() {
+        Err(_) => {
+            debug!("Unable to read PlaydateSDK config from home dir, so using default.");
+            playdate_sdk_path_default()
+        }
+        Ok(cfg) => cfg.sdk_path().map(|p| Ok(p)).unwrap_or_else(|| {
+            debug!("Unable to determine PlaydateSDK path by config, so using default.");
+            playdate_sdk_path_default()
+        }),
+    }
+}
+
+fn playdate_sdk_path_default() -> Result<PathBuf, Error> {
     let home_dir = dirs::home_dir().ok_or(anyhow!("Can't find home dir"))?;
     Ok(home_dir.join(SDK_DIR).join("PlaydateSDK"))
 }