Fix download extraction and resolve "latest" version

Clean the download directory before extracting to prevent errors on
retries. Resolve "latest" to an actual version number before download.
Simplify extraction by stripping components. Also fix bison path check
in install script.

Author: Rusydy-Mekari

bin/download

@@ -24,6 +24,20 @@ download_source() {
   local version=$2
   local download_path=$3
 
+  # Clean download directory to prevent extraction errors on retry
+  if [ -d "$download_path" ]; then
+    rm -rf "${download_path:?}"/*
+  fi
+  mkdir -p "$download_path"
+
+  # Resolve "latest" to actual version number
+  if [ "$version" = "latest" ]; then
+    local script_dir
+    script_dir=$(dirname "${BASH_SOURCE[0]}")
+    version=$("$script_dir/latest-stable")
+    echo "Resolved 'latest' to version $version"
+  fi
+
   local php_version
   php_version=$(get_php_version "$version")
   local download_file="$download_path/php-${php_version}.tar.gz"
@@ -34,16 +48,7 @@ download_source() {
   curl -Lo "$download_file" "$download_url"
 
   echo "Extracting PHP source..."
-  tar -xzf "$download_file" -C "$download_path" --strip-components=0
-
-  # The extracted directory name
-  local extracted_dir="$download_path/php-src-php-${php_version}"
-
-  # Move contents to download_path root if extracted to subdirectory
-  if [ -d "$extracted_dir" ]; then
-    mv "$extracted_dir"/* "$download_path"/
-    rm -rf "$extracted_dir"
-  fi
+  tar -xzf "$download_file" -C "$download_path" --strip-components=1
 
   # Clean up tarball
   rm -f "$download_file"

bin/install

@@ -251,7 +251,7 @@ os_based_configure_options() {
       export ASDF_PKG_MISSING="freetype"
     fi
 
-    if [ -n "$bison_path" ]; then
+    if [ -z "$bison_path" ]; then
       export ASDF_PKG_MISSING="$ASDF_PKG_MISSING bison"
     fi