#!/bin/bash
#
## Wizard Kit: TMUX Launcher

function ask() {
    while :; do
        read -p "$1 [Y/N] " -r answer
        if echo "$answer" | grep -Eiq '^(y|yes|sure)$'; then
            return 0
        elif echo "$answer" | grep -Eiq '^(n|no|nope)$'; then
            return 1
        fi
    done
}

function err () {
    echo "$0:" "$@" >&2
    return 1
}

function launch_in_tmux() {
  # Check for required vars
  [[ -n "${SESSION_NAME:-}" ]] || return $(err "Required variable missing (SESSION_NAME)")
  [[ -n "${WINDOW_NAME:-}" ]] || return $(err "Required variable missing (WINDOW_NAME)")
  [[ -n "${TMUX_CMD:-}" ]] || return $(err "Required variable missing (TMUX_CMD)")

  # Check for running session
  if tmux list-session | grep -q "$SESSION_NAME"; then
      echo "WARNING: tmux session $SESSION_NAME already exists."
      echo ""
      if ask "Connect to current session?"; then
          if [[ -n "${TMUX:-}" ]]; then
              # Running inside TMUX, switch to session
              tmux switch-client -t "$SESSION_NAME"
              if ! jobs %% >/dev/null 2>&1; then
                # No running jobs, try exiting abandoned tmux session
                exit 0
              fi
          else
              # Running outside TMUX, attach to session
              tmux attach-session -t "$SESSION_NAME"
          fi
          return 0
      elif ask "Kill current session and start new session?"; then
          tmux kill-session -t "$SESSION_NAME" || \
              die "Failed to kill session: $SESSION_NAME"
      else
          echo "Aborted."
          return 1
      fi
  fi

  # Start session
  if [[ -n "${TMUX:-}" ]]; then
      # Running inside TMUX, save current session/window names
      ORIGINAL_SESSION_NAME="$(tmux display-message -p '#S')"
      ORIGINAL_WINDOW_NAME="$(tmux display-message -p '#W')"
      tmux rename-session "$SESSION_NAME"
      tmux rename-window "$WINDOW_NAME"
      "$TMUX_CMD" "$@"
      # Restore previous session/window names
      tmux rename-session "${ORIGINAL_SESSION_NAME}"
      tmux rename-window "${ORIGINAL_WINDOW_NAME}"
  else
      # Running outside TMUX, start/attach to session
      tmux new-session -s "$SESSION_NAME" -n "$WINDOW_NAME" "$TMUX_CMD" "$@"
  fi
}