From 244b6e5f286583685053cf71056f2495f05cc92a Mon Sep 17 00:00:00 2001
From: Martin Klepsch <martinklepsch@googlemail.com>
Date: Tue, 9 Jan 2018 12:45:15 +0100
Subject: [PATCH] WIP

---
 build.sh                                     |  2 +-
 src/Boot.java                                | 11 ++++-
 src/boot/bin/BootSnapshotVersionFetcher.java | 43 ++++++++++++++++++++
 3 files changed, 54 insertions(+), 2 deletions(-)
 create mode 100644 src/boot/bin/BootSnapshotVersionFetcher.java

diff --git a/build.sh b/build.sh
index eb37823..1f46aed 100755
--- a/build.sh
+++ b/build.sh
@@ -21,7 +21,7 @@ echo -e "\033[0;33m<< Version: $VERSION >>\033[0m"; \
 
 # Build target/loader.jar which serves as foundation for boot.sh/exe
 
-javac -d target src/Boot.java src/boot/bin/ParentClassLoader.java
+javac -d target src/Boot.java src/boot/bin/ParentClassLoader.java src/boot/bin/BootSnapshotVersionFetcher.java
 cp -r resources/* target/
 jar cef Boot target/loader.jar -C target/ .
 
diff --git a/src/Boot.java b/src/Boot.java
index c249f00..522ccb2 100644
--- a/src/Boot.java
+++ b/src/Boot.java
@@ -1,6 +1,7 @@
 // vim: et:ts=4:sw=4
 
 import boot.bin.ParentClassLoader;
+import boot.bin.BootSnapshotVersionFetcher;
 
 import java.io.*;
 import java.net.*;
@@ -182,7 +183,15 @@ public class Boot {
 
     public static String
     downloadUrl(String version, String name) throws Exception {
-        return String.format("https://github.com/boot-clj/boot/releases/download/%s/%s", version, name); }
+        String urlFormat = "https://clojars.org/repo/boot/base/%s/base-%s-uber.jar";
+        System.out.println("passed name " + name + " compare result " + version.compareTo("2.8"));
+        if (0 < version.compareTo("2.8") && name.equals("boot.jar")) {
+            if (version.endsWith("SNAPSHOT")) {
+                return String.format(urlFormat, version, BootSnapshotVersionFetcher.lastSnapshot(version)); }
+            else {
+                return String.format(urlFormat, version, version); }
+        } else { // 2.7.2 and lower download releases from github
+            return String.format("https://github.com/boot-clj/boot/releases/download/%s/%s", version, name); }}
 
     public static File
     validateBinaryFile(File f) throws Exception {
diff --git a/src/boot/bin/BootSnapshotVersionFetcher.java b/src/boot/bin/BootSnapshotVersionFetcher.java
new file mode 100644
index 0000000..b36beeb
--- /dev/null
+++ b/src/boot/bin/BootSnapshotVersionFetcher.java
@@ -0,0 +1,43 @@
+package boot.bin;
+
+import java.util.ArrayDeque;
+import java.util.Deque;
+import java.util.Arrays;
+import javax.xml.parsers.SAXParser;
+import javax.xml.parsers.SAXParserFactory;
+import org.xml.sax.Attributes;
+import org.xml.sax.SAXException;
+import org.xml.sax.helpers.DefaultHandler;
+
+public class BootSnapshotVersionFetcher {
+
+    private static class MavenMetadataHandler extends DefaultHandler {
+        String snapshotVersion;
+        Deque<String> stack = new ArrayDeque<>();
+
+        String marker[] = {"value", "snapshotVersion", "snapshotVersions", "versioning", "metadata"};
+
+        public String getSnapshotVersion() {
+            return snapshotVersion; }
+
+        public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
+            stack.push(qName); }
+
+        public void endElement(String uri, String localName, String qName) throws SAXException {
+            stack.pop(); }
+
+        public void characters(char ch[], int start, int length) throws SAXException {
+            if (Arrays.equals(stack.toArray(), marker) && snapshotVersion == null) {
+                // String versionString = new String(ch, start, length);
+                // System.out.println("version " + versionString);
+                snapshotVersion = new String(ch, start, length); }}};
+
+    public static String lastSnapshot(String version)  throws Exception {
+        MavenMetadataHandler handler = new MavenMetadataHandler();
+        try { SAXParserFactory factory = SAXParserFactory.newInstance();
+              SAXParser saxParser = factory.newSAXParser();
+              String metadataFile = String.format("https://clojars.org/repo/boot/base/%s/maven-metadata.xml", version);
+              saxParser.parse(metadataFile, handler); }
+        catch (Exception e) { e.printStackTrace(); }
+
+        return handler.getSnapshotVersion(); }}
\ No newline at end of file