1 files changed, 27 insertions, 6 deletions
diff --git a/src/launcher.rs b/src/launcher.rs
index 40d9742..f8be78b 100644
--- a/src/launcher.rs
+++ b/src/launcher.rs
@@ -22,7 +22,7 @@ use std::env::JoinPathsError;
 use std::time::{Instant, SystemTime, UNIX_EPOCH};
 use const_format::formatcp;
 use futures::{StreamExt, TryStreamExt};
-use log::{debug, info, warn};
+use log::{debug, info, trace, warn};
 use reqwest::Client;
 use sha1_smol::Sha1;
 use sysinfo::System;
@@ -137,7 +137,11 @@ pub enum LaunchError {
     InvalidLogId(Option<String>),
 
     // asset errors
-    Assets(AssetError)
+    Assets(AssetError),
+
+    // java runtime errors
+    ResolveJavaRuntime { what: &'static str, error: io::Error },
+    MissingJavaRuntime
 }
 
 impl Display for LaunchError {
@@ -162,7 +166,9 @@ impl Display for LaunchError {
             LaunchError::UnknownLogType(t) => write!(f, "unknown log type: {}", t),
             LaunchError::InvalidLogId(Some(id)) => write!(f, "invalid log id: {}", id),
             LaunchError::InvalidLogId(None) => write!(f, "missing log id"),
-            LaunchError::Assets(e) => write!(f, "failed to fetch assets: {}", e)
+            LaunchError::Assets(e) => write!(f, "failed to fetch assets: {}", e),
+            LaunchError::ResolveJavaRuntime { what, error } => write!(f, "failed to find java runtime ({}): {}", what, error),
+            LaunchError::MissingJavaRuntime => f.write_str("suitable java executable not found")
         }
     }
 }
@@ -181,6 +187,7 @@ impl Error for LaunchError {
             LaunchError::Download { error: e, .. } => Some(e),
             LaunchError::Integrity(e) => Some(e),
             LaunchError::Assets(e) => Some(e),
+            LaunchError::ResolveJavaRuntime { error: e, .. } => Some(e),
             _ => None
         }
     }
@@ -206,7 +213,9 @@ pub struct Launch {
     jvm_args: Vec<OsString>,
     game_args: Vec<OsString>,
     main_class: String,
-    instance_path: PathBuf
+    instance_path: PathBuf,
+    runtime_path: PathBuf,
+    runtime_legacy_launch: bool
 }
 
 struct ProfileFeatureMatcher<'prof> {
@@ -560,7 +569,17 @@ impl Launcher {
                 os.to_string_lossy().to_string()
             });
 
-        info!("Classpath: {classpath}");
+        trace!("Classpath: {classpath}");
+
+        info!("Resolving java runtime environment path");
+        let runtime_path = fs::canonicalize(profile.get_java_runtime().expect("downloading JREs is not supported yet")).await
+            .map_err(|e| LaunchError::ResolveJavaRuntime {what: "resolving jre path", error: e})?;
+        let Some(runtime_exe_path) = runner::find_java(runtime_path.as_path(), profile.is_legacy_launch()).await
+            .map_err(|e| LaunchError::ResolveJavaRuntime {what: "finding java executable", error: e})? else {
+            return Err(LaunchError::MissingJavaRuntime);
+        };
+
+        debug!("Found runtime exe: {}", runtime_exe_path.display());
 
         info!("Deriving launch arguments");
         let info = LaunchInfo {
@@ -593,7 +612,9 @@ impl Launcher {
             jvm_args,
             game_args,
             main_class: main_class.to_string(),
-            instance_path: inst_home
+            instance_path: inst_home,
+            runtime_path: runtime_exe_path,
+            runtime_legacy_launch: profile.is_legacy_launch()
         })
     }
 }