Multi Session Overlap Indicator

#!/usr/bin/env bash

# Multi-Session Overlap Indicator for Claude Code
# Detects concurrent Claude sessions running in parallel

# Read JSON from stdin
read -r input

# Extract current session info
session_id=$(echo "$input" | jq -r '.session_id // "unknown"')
current_workspace=$(echo "$input" | jq -r '.workspace.current_dir // ""')

# Session tracking directory (stores active session metadata)
SESSION_DIR="${HOME}/.claude-code-sessions"
mkdir -p "$SESSION_DIR"

# Current session file
SESSION_FILE="${SESSION_DIR}/${session_id}.active"

# Write current session timestamp and workspace
echo "$(date +%s)|${current_workspace}" > "$SESSION_FILE"

# Cleanup stale sessions (older than 10 minutes = 600 seconds)
CURRENT_TIME=$(date +%s)
for session_file in "$SESSION_DIR"/*.active; do
  if [ -f "$session_file" ]; then
    session_timestamp=$(cut -d'|' -f1 < "$session_file")
    age=$((CURRENT_TIME - session_timestamp))
    if [ $age -gt 600 ]; then
      rm -f "$session_file"
    fi
  fi
done

# Count active sessions
active_sessions=$(find "$SESSION_DIR" -name '*.active' -type f | wc -l | tr -d ' ')

# Check for workspace collisions (multiple sessions in same workspace)
workspace_collision=false
if [ -n "$current_workspace" ]; then
  collision_count=$(grep -l "|${current_workspace}$" "$SESSION_DIR"/*.active 2>/dev/null | wc -l | tr -d ' ')
  if [ "$collision_count" -gt 1 ]; then
    workspace_collision=true
  fi
fi

# Color coding based on session count
if [ $active_sessions -eq 1 ]; then
  SESSION_COLOR="\033[38;5;46m"   # Green: Single session
  SESSION_ICON="●"
  SESSION_STATUS="SOLO"
elif [ $active_sessions -le 3 ]; then
  SESSION_COLOR="\033[38;5;226m"  # Yellow: 2-3 sessions (moderate overlap)
  SESSION_ICON="●●"
  SESSION_STATUS="MULTI"
else
  SESSION_COLOR="\033[38;5;196m"  # Red: 4+ sessions (high overlap, budget concern)
  SESSION_ICON="●●●"
  SESSION_STATUS="OVERLAP!"
fi

# Workspace collision warning
if [ "$workspace_collision" = true ]; then
  COLLISION_WARNING="\033[38;5;208m⚠ WORKSPACE COLLISION\033[0m"
else
  COLLISION_WARNING=""
fi

RESET="\033[0m"

# Build session list visualization
if [ $active_sessions -gt 1 ]; then
  session_list=""
  for i in $(seq 1 $active_sessions); do
    session_list="${session_list}●"
  done
  visual="[${session_list}]"
else
  visual=""
fi

# Output statusline
if [ -n "$COLLISION_WARNING" ]; then
  echo -e "${SESSION_COLOR}${SESSION_ICON} ${SESSION_STATUS}${RESET}: ${active_sessions} active ${visual} | ${COLLISION_WARNING}"
else
  echo -e "${SESSION_COLOR}${SESSION_ICON} ${SESSION_STATUS}${RESET}: ${active_sessions} active ${visual}"
fi

{
  "format": "bash",
  "position": "left",
  "refreshInterval": 2000
}