Merge pull request 'refactor(session): make cmd_continue idempotent with ensure_* functions' (#230) from fix/issue-168 into main

- Add ensure_worktree() - creates worktree if missing, returns status
- Add ensure_session() - creates session if missing, handles inconsistent states
- Add fork_agent() - extracted agent forking logic
- Refactor cmd_continue() to use ensure_* functions (idempotent)
- Make cmd_start() a thin wrapper calling cmd_continue()
- Simplify daemon to always call cmd_continue (no existence check)

This makes cmd_continue truly idempotent - it will:
- Continue existing session if it exists
- Create session and worktree if they don't exist
- Clean and recreate if state is inconsistent

Closes #168

skills/kugetsu/scripts/kugetsu-queue-daemon.sh

@@ -109,28 +109,15 @@ process_task() {
 
     source "$SCRIPT_DIR/kugetsu-session.sh"
 
-    if worktree_exists "$issue_ref" "$WORKTREES_DIR" || [ -f "$SESSIONS_DIR/$(issue_ref_to_filename "$issue_ref").json" ]; then
-        log_file="$LOGS_DIR/delegate-$(date +%s).log"
-        if cmd_continue "$issue_ref" "$message" >> "$log_file" 2>&1; then
-            sleep 1
-            local session_id=$(get_session_id_for_issue "$issue_ref")
-            update_queue_item_state "$queue_id" "notified" "$session_id" ""
-            echo "Task $queue_id continued for $issue_ref"
-        else
-            update_queue_item_state "$queue_id" "error"
-            echo "Task $queue_id ($issue_ref) failed to continue"
-        fi
+    log_file="$LOGS_DIR/delegate-$(date +%s).log"
+    if cmd_continue "$issue_ref" "$message" >> "$log_file" 2>&1; then
+        sleep 1
+        local session_id=$(get_session_id_for_issue "$issue_ref")
+        update_queue_item_state "$queue_id" "notified" "$session_id" ""
+        echo "Task $queue_id continued for $issue_ref"
     else
-        log_file="$LOGS_DIR/delegate-$(date +%s).log"
-        if cmd_start "$issue_ref" "$message" >> "$log_file" 2>&1; then
-            sleep 1
-            local session_id=$(get_session_id_for_issue "$issue_ref")
-            update_queue_item_state "$queue_id" "notified" "$session_id" ""
-            echo "Task $queue_id started for $issue_ref"
-        else
-            update_queue_item_state "$queue_id" "error"
-            echo "Task $queue_id ($issue_ref) failed to start"
-        fi
+        update_queue_item_state "$queue_id" "error"
+        echo "Task $queue_id ($issue_ref) failed to continue"
     fi
 
     release_lock "$issue_ref"

skills/kugetsu/scripts/kugetsu-session.sh

@@ -330,29 +330,48 @@ EOF
     fi
 }
 
-cmd_start() {
-    local issue_ref="${1:-}"
-    local message="${2:-}"
+ensure_worktree() {
+    local issue_ref="$1"
     
-    if [ -z "$issue_ref" ]; then
-        echo "Error: issue ref is required" >&2
-        echo "Usage: kugetsu start <issue-ref> [message]" >&2
-        exit 1
+    if worktree_exists "$issue_ref" "$WORKTREES_DIR"; then
+        log "info" "ensure_worktree" "Worktree already exists for $issue_ref"
+        echo "existed"
+        return 0
     fi
     
-    validate_issue_ref "$issue_ref"
-    
     local base_session_id=$(get_base_session_id)
     if [ -z "$base_session_id" ] || [ "$base_session_id" = "null" ]; then
-        echo "Error: Base session not found. Run 'kugetsu init' first." >&2
-        exit 1
+        log "error" "ensure_worktree" "Base session not found for $issue_ref"
+        echo "error"
+        return 1
     fi
     
+    local active_count=$(count_active_dev_sessions)
+    if [ "$active_count" -ge "${MAX_CONCURRENT_AGENTS:-3}" ]; then
+        log "error" "ensure_worktree" "Max concurrent agents reached for $issue_ref"
+        echo "error"
+        return 1
+    fi
+    
+    if create_worktree "$issue_ref" "$WORKTREES_DIR" 2>&1 | tee >(cat >&2); then
+        log "info" "ensure_worktree" "Created worktree for $issue_ref"
+        echo "created"
+        return 0
+    else
+        log "error" "ensure_worktree" "Failed to create worktree for $issue_ref"
+        echo "error"
+        return 1
+    fi
+}
+
+ensure_session() {
+    local issue_ref="$1"
+    
     local session_file=$(issue_ref_to_filename "$issue_ref")
     local session_path="$SESSIONS_DIR/$session_file"
-    local worktree_exists=false
     
-    if worktree_exists "$issue_ref"; then
+    local worktree_exists=false
+    if worktree_exists "$issue_ref" "$WORKTREES_DIR"; then
         worktree_exists=true
     fi
     
@@ -362,38 +381,46 @@ cmd_start() {
     fi
     
     if $worktree_exists && $session_exists; then
-        echo "Issue '$issue_ref' already has a worktree and session." >&2
-        echo "Use 'kugetsu continue $issue_ref' to continue work." >&2
-        exit 1
+        log "info" "ensure_session" "Session already exists for $issue_ref"
+        echo "continued"
+        return 0
     fi
     
     if $worktree_exists && ! $session_exists; then
-        echo "Warning: Worktree exists but session is missing. Removing worktree to recreate both..." >&2
+        log "warn" "ensure_session" "Worktree exists but session is missing. Removing worktree to recreate both..."
         remove_worktree_for_issue "$issue_ref"
         worktree_exists=false
     fi
     
     if ! $worktree_exists && $session_exists; then
-        echo "Warning: Session exists but worktree is missing. Removing stale session to recreate both..." >&2
+        log "warn" "ensure_session" "Session exists but worktree is missing. Removing stale session..."
         rm -f "$session_path"
         remove_issue_from_index "$issue_ref"
         session_exists=false
     fi
     
-    local active_count=$(count_active_dev_sessions)
-    if [ "$active_count" -ge "${MAX_CONCURRENT_AGENTS:-3}" ]; then
-        echo "Error: Max concurrent agents (${MAX_CONCURRENT_AGENTS:-3}) reached. Use 'kugetsu continue' or wait for an agent to finish." >&2
-        exit 1
+    if ! $worktree_exists; then
+        local wt_status=$(ensure_worktree "$issue_ref")
+        if [ "$wt_status" != "created" ] && [ "$wt_status" != "existed" ]; then
+            log "error" "ensure_session" "Failed to ensure worktree for $issue_ref"
+            echo "error"
+            return 1
+        fi
     fi
     
-    create_worktree "$issue_ref" "$WORKTREES_DIR"
+    local base_session_id=$(get_base_session_id)
+    if [ -z "$base_session_id" ] || [ "$base_session_id" = "null" ]; then
+        log "error" "ensure_session" "Base session not found for $issue_ref"
+        echo "error"
+        return 1
+    fi
     
     local new_session_id=$(create_session "$base_session_id")
     
     if [ -z "$new_session_id" ]; then
-        echo "Error: Could not create session" >&2
-        remove_worktree_for_issue "$issue_ref"
-        exit 1
+        log "error" "ensure_session" "Could not create session for $issue_ref"
+        echo "error"
+        return 1
     fi
     
     local worktree_path=$(issue_ref_to_worktree_path "$issue_ref")
@@ -403,89 +430,87 @@ cmd_start() {
     
     add_issue_to_index "$issue_ref" "$session_file"
     
-    local dev_message=$(build_dev_agent_message "$issue_ref" "$message")
-    
-    load_agent_env "dev"
-    
-    cd "$worktree_path"
-    local sanitized_id=$(echo "$new_session_id" | sed 's/[^a-zA-Z0-9_-]/_/g')
-    mkdir -p "$worktree_path/.kugetsu"
-    if [ ! -f "$worktree_path/.gitignore" ] || ! grep -q "^.kugetsu/" "$worktree_path/.gitignore"; then
-        echo ".kugetsu/" >> "$worktree_path/.gitignore" 2>/dev/null || true
-    fi
-    local msg_file="$worktree_path/.kugetsu/msg.txt"
-    printf '%s' "$dev_message" > "$msg_file"
-    nohup sh -c "GITEA_TOKEN='${GITEA_TOKEN:-}' opencode run '@$msg_file' --session '$new_session_id'" >> "$LOGS_DIR/dev-$sanitized_id.log" 2>&1 &
-    
-    echo "Session started for '$issue_ref': $new_session_id"
-    echo "Worktree: $worktree_path"
+    log "info" "ensure_session" "Created session for $issue_ref: $new_session_id"
+    echo "created"
+    return 0
 }
 
-cmd_continue() {
-    local session_name=""
-    local message=""
-    local args=("$@")
-
-    args=$(set_debug_mode "${args[@]}")
-
-    for arg in $args; do
-        if [ -z "$session_name" ]; then
-            session_name="$arg"
-        else
-            message="${message}${message:+ }${arg}"
-        fi
-    done
+fork_agent() {
+    local session_id="$1"
+    local worktree_path="$2"
+    local message="$3"
     
-    if [ -z "$session_name" ]; then
-        echo "Error: issue ref is required" >&2
-        echo "Usage: kugetsu continue <issue-ref> [message]" >&2
-        exit 1
-    fi
-    
-    validate_issue_ref "$session_name"
-    
-    local session_file=$(get_session_for_issue "$session_name")
-    if [ -z "$session_file" ] || [ "$session_file" = "null" ]; then
-        echo "Error: No session found for '$session_name'" >&2
-        echo "Use 'kugetsu start $session_name' to create a new session." >&2
-        exit 1
-    fi
-    
-    local session_path="$SESSIONS_DIR/$session_file"
-    
-    if [ ! -f "$session_path" ]; then
-        echo "Error: Session file not found: $session_path" >&2
-        exit 1
+    if [ -z "$worktree_path" ] || [ ! -d "$worktree_path" ]; then
+        log "error" "fork_agent" "Invalid worktree path: $worktree_path"
+        echo "error"
+        return 1
     fi
     
     load_agent_env "dev"
     
-    local opencode_session_id=$(python3 -c "import json; print(json.load(open('$session_path')).get('opencode_session_id', ''))" 2>/dev/null || echo "")
-    local worktree_path=$(python3 -c "import json; print(json.load(open('$session_path')).get('worktree_path', ''))" 2>/dev/null || echo "")
-    local issue_ref=$(python3 -c "import json; print(json.load(open('$session_path')).get('issue_ref', ''))" 2>/dev/null || echo "")
-    
-    if [ -z "$worktree_path" ] || [ ! -d "$worktree_path" ]; then
-        echo "Warning: Worktree is missing for '$session_name'. Recovering..." >&2
-        rm -f "$session_path"
-        remove_issue_from_index "$session_name"
-        echo "Calling cmd_start to create new session and worktree..." >&2
-        cmd_start "$session_name" "$message"
-        return $?
-    fi
-    
-    if [ -z "$message" ]; then
-        message=$(build_dev_agent_message "$issue_ref" "")
-    fi
-    
     cd "$worktree_path"
-    local sanitized_id=$(echo "$opencode_session_id" | sed 's/[^a-zA-Z0-9_-]/_/g')
+    local sanitized_id=$(echo "$session_id" | sed 's/[^a-zA-Z0-9_-]/_/g')
     mkdir -p "$worktree_path/.kugetsu"
     if [ ! -f "$worktree_path/.gitignore" ] || ! grep -q "^.kugetsu/" "$worktree_path/.gitignore"; then
         echo ".kugetsu/" >> "$worktree_path/.gitignore" 2>/dev/null || true
     fi
     local msg_file="$worktree_path/.kugetsu/msg.txt"
     printf '%s' "$message" > "$msg_file"
-    nohup sh -c "GITEA_TOKEN='${GITEA_TOKEN:-}' opencode run '@$msg_file' --session '$opencode_session_id'" >> "$LOGS_DIR/dev-$sanitized_id.log" 2>&1 &
+    nohup sh -c "GITEA_TOKEN='${GITEA_TOKEN:-}' opencode run '@$msg_file' --session '$session_id'" >> "$LOGS_DIR/dev-$sanitized_id.log" 2>&1 &
+    
+    log "info" "fork_agent" "Forked agent for session $session_id in $worktree_path"
+    echo "forked"
+    return 0
+}
+
+cmd_start() {
+    cmd_continue "$@"
+}
+
+cmd_continue() {
+    local issue_ref="${1:-}"
+    local message="${2:-}"
+    
+    if [ -z "$issue_ref" ]; then
+        echo "Error: issue ref is required" >&2
+        echo "Usage: kugetsu continue <issue-ref> [message]" >&2
+        exit 1
+    fi
+    
+    validate_issue_ref "$issue_ref"
+    
+    if [ -z "$message" ]; then
+        message=$(build_dev_agent_message "$issue_ref" "")
+    fi
+    
+    local worktree_status=$(ensure_worktree "$issue_ref")
+    if [ "$worktree_status" = "error" ]; then
+        echo "Error: Failed to ensure worktree for '$issue_ref'" >&2
+        exit 1
+    fi
+    
+    local session_status=$(ensure_session "$issue_ref")
+    if [ "$session_status" = "error" ]; then
+        echo "Error: Failed to ensure session for '$issue_ref'" >&2
+        exit 1
+    fi
+    
+    local session_file=$(issue_ref_to_filename "$issue_ref")
+    local session_path="$SESSIONS_DIR/$session_file"
+    local opencode_session_id=$(python3 -c "import json; print(json.load(open('$session_path')).get('opencode_session_id', ''))" 2>/dev/null || echo "")
+    local worktree_path=$(python3 -c "import json; print(json.load(open('$session_path')).get('worktree_path', ''))" 2>/dev/null || echo "")
+    
+    local fork_status=$(fork_agent "$opencode_session_id" "$worktree_path" "$message")
+    if [ "$fork_status" = "error" ]; then
+        echo "Error: Failed to fork agent for '$issue_ref'" >&2
+        exit 1
+    fi
+    
+    log "info" "cmd_continue" "Result for $issue_ref: worktree=$worktree_status session=$session_status fork=$fork_status"
+    
+    echo "Session continued for '$issue_ref': $opencode_session_id"
+    echo "Worktree: $worktree_path"
+    echo "${worktree_status}-${session_status}-${fork_status}"
 }
 
 cmd_list() {