tmux/tmux.conf

# Set global hooks to perform actions when events occur
set-hook -g session-created 'run ~/.config/tmux/hooks/session-create.sh'

# Set the tmux version to check for command support
run 'tmux setenv -g TMUX_VERSION $(tmux -V | cut -c 6-8)'

# Use vim keybindings in copy mode
set -g mode-keys vi

# Change prefix to C-Space
unbind C-b
set -g prefix C-Space
bind Space send-prefix

# Address vim mode switching delay
set -s escape-time 0

# Increase scrollback buffer size
set -g history-limit 1000000

# Set tmux messages display time to 4 seconds
set -g display-time 4000

# Refresh 'status-left' and 'status-right' more often
set -g status-interval 2

# Upgrade $TERM
set -g default-terminal "xterm-256color"

# Focus events enabled for terminals that support them
set -g focus-events on

# TODO: Change this comment to something that explains the setting
# super useful when using "grouped sessions" and multi-monitor setup
setw -g aggressive-resize on

# Start window & pane index at 1
set -g pane-base-index 1

# Enable mouse support
set-option -g mouse on
# Prevent mouse click up events exiting copy mode
unbind -T copy-mode-vi MouseDragEnd1Pane

# Enable changing cursor shape per pane, vim or zsh should emit escape
# sequences to change cursor shape.
# iTerm2 only requires this before tmux 2.9
if '[ -n $ITERM_PROFILE ] && [[ "$TMUX_VERSION" < "2.9" ]]' \
  'set -ga terminal-overrides "*:Ss=\E]1337;CursorShape=%p1%d\7"'
# VTE compatible terminals.
if '[ ! -n $ITERM_PROFILE ]' \
  'set -ga terminal-overrides "*:Ss=\E[%p1%d q:Se=\E[2 q"'

# Enable strikethrough on VTE compatible terminals.
set -ga terminal-overrides 'xterm*:smxx=\E[9m'

# Set only on macOS where it's required
if -b '[ "`uname`" = "Darwin" ]' \
  'set -g default-command "reattach-to-user-namespace -l $SHELL"'

# Restore old next/previous window bindings
bind C-n next-window
bind C-p previous-window

# Make new splits open in current directory
bind '"' split-window -c '#{pane_current_path}'
bind '%' split-window -h -c '#{pane_current_path}'

# Change word separators to better match Vim.
set -g word-separators "<>(){}[]/'\";@*+,.-_=!£$%^&:#~?`¬|\\ "

# Integrate pane selection with vim
in_vim='tmux show-window-options | grep -q "@vim#{pane_id}"'
bind -n C-h if $in_vim 'send-keys C-h' 'select-pane -L'
bind -n C-j if $in_vim 'send-keys C-j' 'select-pane -D'
bind -n C-k if $in_vim 'send-keys C-k' 'select-pane -U'
bind -n C-l if $in_vim 'send-keys C-l' 'select-pane -R'

# Integrate urlscan or fallback to urlview
if -b 'which urlscan' \
  'bind u capture-pane \; split-window "tmux show-buffer | urlscan"' \
  'bind u capture-pane \; split-window "tmux show-buffer | urlview -"'

# Unbind copy mode defaults so pane selection works
unbind -T copy-mode-vi C-h
unbind -T copy-mode-vi C-j
# Enter copy mode with C-U
bind C-u copy-mode -u
# Begin selection in copy mode with v not Space
bind -T copy-mode-vi v send-keys -X begin-selection

# Enable mouse scrolling up in alternate buffers.
# If #{mouse_any_flag} is 1 the pane is running with mouse support, e.g. vim.
# If #{alternate_on} is 1 the terminal is in alternate buffer mode, e.g. less.
# If #{pane_in_mode} is 1 the pane is in copy-mode.
bind -n WheelUpPane \
  if -Ft= "#{mouse_any_flag}" \
    "send-keys -M" \
    "if -Ft= \"#{alternate_on}\" \
      \"send-keys -t= Up ; \
        send-keys -t= Up ; \
        send-keys -t= Up ; \" \
      \"select-pane -t= ; \
        if -Ft= '#{pane_in_mode}' \
          'send-keys -M' \
          'copy-mode -e ; send-keys -M' \" "
# Emulate mouse scrolling down in alternate buffers.
bind -n WheelDownPane \
  if -Ft= "#{mouse_any_flag}" \
    "send-keys -M" \
    "if -Ft= \"#{alternate_on}\" \
      \"send-keys -t= Down ; \
        send-keys -t= Down ; \
        send-keys -t= Down ; \" \
      \"select-pane -t= ; \
        send-keys -M\" "

# Yank to the system clipboard in copy mode.
# TODO: reattach-to-user-namespace not necessary with tmux > 2.6
if -b '[ "`uname`" = "Darwin" ]' \
  'bind -T copy-mode-vi y send-keys -X copy-pipe "reattach-to-user-namespace pbcopy"'
# When not in WSL2 use xsel, when in WSL use win32yank.exe to avoid UI lockups.
if -b '[ "$WSLENV" = "" ]' \
  'bind -T copy-mode-vi y send-keys -X copy-pipe "xsel -i --clipboard"' \
  'bind -T copy-mode-vi y send-keys -X copy-pipe "win32yank.exe -i -crlf"'

# Left status style
if -b '[ "$WSL_DISTRO_NAME" != "" ]' \
  'setw -g status-left " #(hostname)|#{WSL_DISTRO_NAME}|#{session_name}"' \
  'setw -g status-left " #(hostname)|#{session_name}"'
setw -g status-left-style fg=colour240,bg=colour233
setw -g status-left-length 32

# Centre status style
setw -g status-style fg=colour240,bg=colour233

# Right status style shows system info, date, and time.
setw -g status-right "#[fg=colour240]#(cat ~/.cache/tmux/system-info)#[fg=white] %a %d-%m-%y %H:%M "
setw -g status-right-style fg=white,bg=colour233
if -b '[ "`uname`" != "Darwin" ]' \
  'run "tmux setw -g status-right-length $((`nproc --all` + 32))"'

# Active window status style
setw -g window-status-current-format " #{window_index}: #{window_name}"
setw -g window-status-current-style fg=white,bg=colour233

# Inactive window status style
setw -g window-status-format " #{window_index}: #{window_name}"
setw -g window-status-style fg=colour240,bg=colour233

# Pane border style
set -g pane-border-style fg=colour233,bg=colour233
set -g pane-active-border-style fg=colour235,bg=colour235

# Command line window list selection
set-window-option -g mode-style fg=white,bg=colour237
set-option -g message-style fg=white,bg=colour237