read_config_file(): Update to get the config from `config.toml`

Use XDG handling from `state_load_map_group()` to do basically the same
thing here for reading the config from a `config.toml` file.

Use 'error-chain' to handle the `Result`s more easily. No more nested
pattern matching, we'll just have to unwrap one `Result` and write the
error to stderr in an FFI function.

3 files changed, 26 insertions, 4 deletions

diff --git a/src/config.rs b/src/config.rs
index 9962ba0..1e75575 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -1,5 +1,10 @@
+use std::fs;
+
 use getopts::Options;
 use toml;
+use xdg;
+
+use errors::*;
 
 type Milliseconds = u16;
 
@@ -61,9 +66,15 @@ pub fn parse_args<'a>(args: &[String], config: &'a mut Config) -> &'a mut Config
     config
 }
 
-// TODO: Get config file from .config/dome-key/config.toml
-pub fn read_config_file() -> Config {
-    let config = toml::from_str("").unwrap();
+pub fn read_config_file() -> Result<Config> {
+    let xdg_dirs = xdg::BaseDirectories::with_prefix("dome-key")?;
+    let config_file = xdg_dirs.find_config_file("config.toml")
+        .chain_err(|| "config home path contains invalid unicode")?;
+    let config_str = fs::read_to_string(config_file)
+        .chain_err(|| "failed to read config file")?;
 
-    config
+    let config = toml::from_str(&config_str)
+        .chain_err(|| "failed to parse config file")?;
+
+    Ok(config)
 }
diff --git a/src/errors.rs b/src/errors.rs
new file mode 100644
index 0000000..beafc9f
--- /dev/null
+++ b/src/errors.rs
@@ -0,0 +1,7 @@
+use xdg;
+
+error_chain! {
+    foreign_links {
+        Xdg(xdg::BaseDirectoriesError);
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index d5af695..801591c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,6 +6,9 @@ extern crate cocoa;
 #[macro_use]
 extern crate combine;
 extern crate core_graphics;
+
+#[macro_use]
+extern crate error_chain;
 extern crate foreign_types;
 extern crate getopts;
 extern crate libc;
@@ -25,6 +28,7 @@ extern crate xdg;
 mod autopilot_internal;
 mod cocoa_bridge;
 mod config;
+mod errors;
 mod key_code;
 mod parser;