Improve branch handling with enhanced remote synchronization and error handling

entrypoint.sh

@@ -43,7 +43,7 @@ fi
 # Setting branch name
 BRANCH="${INPUT_TARGET_BRANCH:-$(git symbolic-ref --short -q HEAD)}"
 # Add timestamp to branch name
-if [[ "${INPUT_ADD_TIMESTAMP}" == "true" && -n ${FILES_CHANGED} ]]; then
+if [[ "${INPUT_ADD_TIMESTAMP}" == "true" ]]; then
   TIMESTAMP=$(date -u +"%Y-%m-%dT%H-%M-%SZ")
   if [[ -n ${BRANCH} ]]; then
     BRANCH="${BRANCH}-${TIMESTAMP}"
@@ -53,9 +53,73 @@ if [[ "${INPUT_ADD_TIMESTAMP}" == "true" && -n ${FILES_CHANGED} ]]; then
 fi
 echo -e "\n[INFO] Target branch: ${BRANCH}"
 
-# Create a new branch
-if [[ (-n "${INPUT_TARGET_BRANCH}" || "${INPUT_ADD_TIMESTAMP}" == "true") && -n ${FILES_CHANGED} ]]; then
-  git checkout -b "${BRANCH}"
+# Enhanced branch handling with proper remote synchronization
+if [[ -n "${INPUT_TARGET_BRANCH}" || "${INPUT_ADD_TIMESTAMP}" == "true" ]]; then
+  # Fetch latest changes from remote
+  echo "[INFO] Fetching latest changes from remote..."
+  git fetch origin || {
+    echo "[WARNING] Could not fetch from remote. Proceeding with local operations."
+  }
+
+  # Check if remote branch exists
+  REMOTE_BRANCH_EXISTS=$(git ls-remote --heads origin "${BRANCH}" 2>/dev/null | wc -l)
+
+  # Improved main branch detection
+  MAIN_BRANCH="main"
+  if git show-ref --verify --quiet "refs/remotes/origin/main"; then
+    MAIN_BRANCH="main"
+  elif git show-ref --verify --quiet "refs/remotes/origin/master"; then
+    MAIN_BRANCH="master"
+  else
+    # Try to get default branch from remote HEAD
+    MAIN_BRANCH=$(git symbolic-ref refs/remotes/origin/HEAD 2>/dev/null | sed 's@^refs/remotes/origin/@@' || echo "main")
+  fi
+  echo "[INFO] Detected main branch: ${MAIN_BRANCH}"
+
+  if [[ ${REMOTE_BRANCH_EXISTS} -gt 0 ]]; then
+    echo "[INFO] Remote branch '${BRANCH}' exists, checking out and updating..."
+    # Check if local branch exists
+    if git show-ref --verify --quiet "refs/heads/${BRANCH}"; then
+      echo "[INFO] Local branch '${BRANCH}' exists, switching to it..."
+      git checkout "${BRANCH}" || {
+        echo "[ERROR] Failed to checkout branch ${BRANCH}"
+        exit 1
+      }
+    else
+      echo "[INFO] Creating local branch '${BRANCH}' from remote..."
+      git checkout -b "${BRANCH}" "origin/${BRANCH}" || {
+        echo "[ERROR] Failed to create local branch from remote"
+        exit 1
+      }
+    fi
+
+    # Ensure branch is up-to-date with main/master (only if they're different branches)
+    if [[ "${BRANCH}" != "${MAIN_BRANCH}" ]] && git show-ref --verify --quiet "refs/remotes/origin/${MAIN_BRANCH}"; then
+      echo "[INFO] Rebasing branch onto ${MAIN_BRANCH}..."
+      git rebase "origin/${MAIN_BRANCH}" || {
+        echo "[WARNING] Rebase onto ${MAIN_BRANCH} failed. This may indicate conflicts."
+        echo "[INFO] Attempting to abort the rebase and continue without sync..."
+        git rebase --abort 2>/dev/null || true
+        echo "[INFO] Branch will remain at its current state without sync to ${MAIN_BRANCH}"
+      }
+    fi
+  else
+    echo "[INFO] Remote branch '${BRANCH}' does not exist, creating new branch..."
+    # Ensure starting from the latest main/master
+    if git show-ref --verify --quiet "refs/remotes/origin/${MAIN_BRANCH}"; then
+      echo "[INFO] Creating branch from latest ${MAIN_BRANCH}..."
+      git checkout -b "${BRANCH}" "origin/${MAIN_BRANCH}" || {
+        echo "[ERROR] Failed to create branch from ${MAIN_BRANCH}"
+        exit 1
+      }
+    else
+      echo "[INFO] Creating branch from current HEAD..."
+      git checkout -b "${BRANCH}" || {
+        echo "[ERROR] Failed to create branch from HEAD"
+        exit 1
+      }
+    fi
+  fi
 fi
 
 # Create an auto commit
@@ -104,9 +168,16 @@ if [[ "${INPUT_FORCE}" == "true" ]]; then
 elif [[ "${INPUT_FORCE_WITH_LEASE}" == "true" ]]; then
   echo "[INFO] Force pushing changes with lease"
   git push --force-with-lease origin "${BRANCH}"
-elif [[ -n ${FILES_CHANGED} || "${INPUT_AMEND}" == "true" ]]; then
+elif [[ -n ${FILES_CHANGED} || "${INPUT_AMEND}" == "true" || -n "${INPUT_TARGET_BRANCH}" ]]; then
   echo "[INFO] Pushing changes"
-  git push origin "${BRANCH}"
+  # Check if branch has upstream tracking
+  if git rev-parse --abbrev-ref "${BRANCH}@{upstream}" >/dev/null 2>&1; then
+    echo "[INFO] Branch has upstream, pushing normally"
+    git push origin "${BRANCH}"
+  else
+    echo "[INFO] Branch has no upstream, setting upstream on push"
+    git push -u origin "${BRANCH}"
+  fi
 fi
 
 # Finish