Interactive TMUX session selection / killing / creation

.bashrc

#!/bin/bash
#
# Place this into your .bashrc after installing FZF,
# Then update your .tmux.conf and create key-bindings. Example:
#
# unbind s
# bind   s run "tmux new-window -n 'Switch Session' 'bash -ci tmux_select_session'"
# unbind K
# bind   K run "tmux new-window -n 'Kill Session' 'bash -ci tmux_kill_session'"
# unbind C
# bind   C run "tmux new-window -n 'Create Session' 'bash -ci tmux_create_session'"
# unbind C-c
# bind   C-c run "tmux new-window -n 'Create Session' 'bash -ci PROJECT_PATHS= tmux_create_session'"

PROJECT_PATHS=~/projects

if [[ -f ~/.fzf.bash ]]; then
	source ~/.fzf.bash

	_tmux_select_session () (
		set -eo pipefail
		local -r prompt=$1
		local -r fmt='#{session_id}:|#S|(#{session_attached} attached)'
		{ tmux display-message -p -F "$fmt" && tmux list-sessions -F "$fmt"; } \
			| awk '!seen[$1]++' \
			| column -t -s'|' \
			| fzf -q'$' --reverse --prompt "$prompt> " \
			| cut -d':' -f1
	)

	_find_existing_sid () (
		set -eo pipefail
		local -r name=$1
		sid=$(tmux list-sessions -F '#{session_name}:#{session_id}' \
			| grep "$name" \
			| head -n 1 \
			| cut -d ':' -f 2
		)

		if [ -n "$sid" ]; then
			echo "$sid"
			return 0
		else
			return 1
		fi
	)

	# Select selected tmux session
	# Note: To be bound to a tmux key in from .tmux.conf
	# Example: bind-key s run "tmux new-window -n 'Switch Session' 'bash -ci tmux_select_session'"
	tmux_select_session () (
		set -eo pipefail
		_tmux_select_session 'switch session' | xargs tmux switch-client -t
	)

	# Kill selected tmux session
	# Note: To be bound to a tmux key in from .tmux.conf
	# Example: bind-key K run "tmux new-window -n 'Kill Session' 'bash -ci tmux_kill_session'"
	tmux_kill_session () (
		set -eo pipefail
		_tmux_select_session 'kill session' \
			| {
				read -r id
				echo "$id"
				next=$(tmux list-sessions -F '#{session_id}' | grep -v -F "$id" | head -n1)
				if [ -n "$next" ]; then
					tmux switch-client -t "$next"
				fi && tmux kill-session -t "$id"
			}
	)

	tmux_session_name () {
		sed <<< "$1" 's/[.:]/-/g'
	}

	# Create a new tmux session
	# Note: we must spawn the sessions in detached mode and the use
	# `switch-client` to attach to them. Otherwise we'd get an error saying
	# that the "terminal is not available"
	# Note: To be bound to a tmux key in from .tmux.conf
	# Example: bind-key C run "tmux new-window -n 'Create Session' 'bash -ci tmux_create_session'"
	tmux_create_session () (
		unset TMUX
		set -eo pipefail
		local new_session_id
		{
			new_session_id=$(
				set -eo pipefail
				if [ -z "$PROJECT_PATHS" ]; then
					echo 'Create new session (Ctrl-C to cancel):'
					echo 'Set $PROJECT_PATHS to streamline this process.'
					echo
					read -rep "Set working directory (default: \"$PWD\"):"$'\n> ' dir && \
					if [ -z "$dir" ]; then dir=$PWD; fi && \
					echo
					read -rp "Set name (default \"${dir##*/}\"):"$'\n> ' name && \
					if [ -z "$name" ]; then name=${dir##*/}; fi
					tmux new-session -d -c "$dir" -n "$name" -s "$(tmux_session_name "$name")" -P -F "#{session_id}"
				else
					local projects=(${PROJECT_PATHS//:/ })
					for dir in "${projects[@]}"; do
						if [ -d "$dir" ]; then
							find "${dir%*/}" -maxdepth 1 -type d | tail -n+2
						fi
					done \
						| awk '!seen[$1]++' \
						| fzf --reverse --prompt 'Create new session - choose project: ' --expect='~' \
						| {
							read -r key;
							if [[ "$key" == '~' ]]; then
								tmux new-session -d -c ~ -P -F "#{session_id}"
							else
								read -r dir;
								name=${dir##*/}
								_find_existing_sid "$name" || {
									tmux new-session -d -c "$dir" -n "$name" -s "$(tmux_session_name "$name")" -P -F "#{session_id}"
								}
							fi
						}
				fi
			) && tmux switch-client -t "$new_session_id"
		}
	)
fi