feat(java): integrate Adoptium API for Java runtime download

Add automatic Java (Temurin) download and installation feature:

- Add Adoptium API v3 integration to fetch latest Java releases
- Support JRE and JDK image types with version selection (8/11/17/21)
- Implement platform detection for macOS, Linux, and Windows
- Add SHA256 checksum verification for downloaded archives
- Add tar.gz extraction support with Unix permission preservation
- Handle macOS-specific Java path structure (Contents/Home/bin)
- Add frontend UI with version selector and download progress
- Register Tauri commands: fetch_adoptium_java, download_adoptium_java,
  fetch_available_java_versions

Dependencies added: sha2, flate2, tar, dirs

1 files changed, 75 insertions, 0 deletions

diff --git a/src-tauri/src/utils/zip.rs b/src-tauri/src/utils/zip.rs
index a03c975..dfe1214 100644
--- a/src-tauri/src/utils/zip.rs
+++ b/src-tauri/src/utils/zip.rs
@@ -1,5 +1,7 @@
+use flate2::read::GzDecoder;
 use std::fs;
 use std::path::Path;
+use tar::Archive;
 
 pub fn extract_zip(zip_path: &Path, extract_to: &Path) -> Result<(), String> {
     let file = fs::File::open(zip_path)
@@ -38,3 +40,76 @@ pub fn extract_zip(zip_path: &Path, extract_to: &Path) -> Result<(), String> {
 
     Ok(())
 }
+
+/// Extract a tar.gz archive
+///
+/// Adoptium's tar.gz archives usually contain a top-level directory, such as `jdk-21.0.5+11-jre/`.
+/// This function returns the name of that directory to facilitate locating `bin/java` afterwards.
+pub fn extract_tar_gz(archive_path: &Path, extract_to: &Path) -> Result<String, String> {
+    let file = fs::File::open(archive_path)
+        .map_err(|e| format!("Failed to open tar.gz {}: {}", archive_path.display(), e))?;
+
+    let decoder = GzDecoder::new(file);
+    let mut archive = Archive::new(decoder);
+
+    // Ensure the target directory exists
+    fs::create_dir_all(extract_to)
+        .map_err(|e| format!("Failed to create extract directory: {}", e))?;
+
+    // Track the top-level directory name
+    let mut top_level_dir: Option<String> = None;
+
+    for entry in archive
+        .entries()
+        .map_err(|e| format!("Failed to read tar entries: {}", e))?
+    {
+        let mut entry = entry.map_err(|e| format!("Failed to read tar entry: {}", e))?;
+        let entry_path = entry
+            .path()
+            .map_err(|e| format!("Failed to get entry path: {}", e))?
+            .into_owned();
+
+        // Extract the top-level directory name (the first path component)
+        if top_level_dir.is_none() {
+            if let Some(first_component) = entry_path.components().next() {
+                let component_str = first_component.as_os_str().to_string_lossy().to_string();
+                if !component_str.is_empty() && component_str != "." {
+                    top_level_dir = Some(component_str);
+                }
+            }
+        }
+
+        let outpath = extract_to.join(&entry_path);
+
+        if entry.header().entry_type().is_dir() {
+            fs::create_dir_all(&outpath)
+                .map_err(|e| format!("Failed to create directory {}: {}", outpath.display(), e))?;
+        } else {
+            // Ensure parent directory exists
+            if let Some(parent) = outpath.parent() {
+                if !parent.exists() {
+                    fs::create_dir_all(parent)
+                        .map_err(|e| format!("Failed to create parent dir: {}", e))?;
+                }
+            }
+
+            let mut outfile = fs::File::create(&outpath)
+                .map_err(|e| format!("Failed to create file {}: {}", outpath.display(), e))?;
+
+            std::io::copy(&mut entry, &mut outfile)
+                .map_err(|e| format!("Failed to extract file: {}", e))?;
+
+            // Set executable permissions on Unix systems
+            #[cfg(unix)]
+            {
+                use std::os::unix::fs::PermissionsExt;
+                if let Ok(mode) = entry.header().mode() {
+                    let permissions = fs::Permissions::from_mode(mode);
+                    let _ = fs::set_permissions(&outpath, permissions);
+                }
+            }
+        }
+    }
+
+    top_level_dir.ok_or_else(|| "Archive appears to be empty".to_string())
+}