.tmux.conf

# PastLeo's ~/.tmux.conf
# for tmux -V >= 2.9

# -----------------------------
# Global settings
# -----------------------------

# scrollback buffer n lines
set -g history-limit 5000

# listen for activity on all windows 
set -g bell-action any

# start window indexing at 1 window so the <prefix> 1 is easier to reach
set -g base-index 1

# enable 24bit true color for vim termguicolors according to ~/.shrc.once
if-shell '[ -n "$TERM_RGB" ]' \
  "set -ag terminal-overrides ',xterm-256color:RGB'"

# xterm-style function key sequences
setw -g xterm-keys on

# control automatic window renaming
setw -g automatic-rename off

# enable wm window titles
set -g set-titles on

# remove <esc> key press delay
set -sg escape-time 0

SET_DEFAULT_SHELL='tmux set-option -g default-shell $TMUX_DEFAULT_SHELL'
if-shell '[ -n "$TMUX_DEFAULT_SHELL" ]' \
  "run-shell '${SET_DEFAULT_SHELL}'"

# -----------------------------
# Key bindings
# -----------------------------

# set <prefix> key to C-a
set-option -g prefix C-a

# use C-a again to send ctrl-a to inner session
bind-key C-a send-prefix

# detach session, keeping the program running
bind-key d detach

# Create window
bind-key -r n new-window
bind-key -r C-n new-window
bind-key -r N new-window -c '#{pane_current_path}'

# split windows (create pane)
bind-key _ split-window -v -c '#{pane_current_path}'
bind-key | split-window -h -c '#{pane_current_path}'

# kill current pane when the inner process is unable to exit for whatever reason
bind-key q confirm-before kill-pane

# <prefix> or Ctrl- or <prefix> Ctrl-
#   k --- previous pane
# h   l --- previous window / next window
#   j --- next pane

# navigate windows
unbind-key l
bind-key h select-window -t :-
bind-key C-h select-window -t :-
bind-key -n C-h select-window -t :-
bind-key l select-window -t :+
bind-key C-l select-window -t :+
bind-key -n C-l select-window -t :+

# navigate panes
bind-key j select-pane -t :.-
bind-key C-j select-pane -t :.-
bind-key -n C-j select-pane -t :.-
bind-key k select-pane -t :.+
bind-key C-k select-pane -t :.+
bind-key -n C-k select-pane -t :.+

# rename title
bind-key , command-prompt "rename-window %%"

# move the split line (resize pane)
# <prefix> shift-
#   k --- up
# h   l --- left / right
#   j --- down
bind-key -r H resize-pane -L 3 
bind-key -r L resize-pane -R 3
bind-key -r K resize-pane -U 1
bind-key -r J resize-pane -D 1

# move (swap) panes and windows
# <prefix> alt-
#   k --- move pane next
# h   l --- move window left / move window right
#   j --- move pane previous
bind-key -r M-h swap-window -t :- \; select-window -t :-
bind-key -r M-j swap-pane -D
bind-key -r M-k swap-pane -U
bind-key -r M-l swap-window -t :+ \; select-window -t :+

# change window pane layouts
bind-key -r M-f next-layout

# zoom a pane between full-screen and pane-size
bind-key -r z resize-pane -Z
bind-key -n C-z resize-pane -Z

# vi-style controls for copy mode
setw -g mode-keys vi

# C-v directly to enter vi-mode
bind-key [ copy-mode \; set mouse off
bind-key v copy-mode \; set mouse off
bind-key -n C-v copy-mode \; set mouse off

# select and copy like vi in vi-mode
bind-key -T copy-mode-vi v send -X begin-selection
bind-key -T copy-mode-vi y send -X copy-selection
# if encounter incompatible with send-keys/send -X, use lagacy setting:
# bind-key -t vi-copy 'v' begin-selection
# bind-key -t vi-copy 'y' copy-selection

# C-] directly to paste
bind-key ] paste-buffer
bind-key p paste-buffer
bind-key -n C-] paste-buffer

# enable navigation in vi mode
bind-key -T copy-mode-vi C-h select-window -t :-
bind-key -T copy-mode-vi C-l select-window -t :+
bind-key -T copy-mode-vi C-j select-pane -t :.-
bind-key -T copy-mode-vi C-k select-pane -t :.+

set -g mouse on

bind-key m set -g mouse on \; display "Mouse mode on"
bind-key M set -g mouse off \; display "Mouse mode off"

bind-key -T copy-mode-vi C-k send-keys -X cancel \; set mouse on
bind-key -T copy-mode-vi q send-keys -X cancel \; set mouse on

## Other useful commands

# open a man page in new pane, using q to leave
bind-key / command-prompt -p 'man ' "split-window -h 'exec man %%'"
bind-key r command-prompt -p 'Command >> ' "split-window -c '#{pane_current_path}' -h '%%; echo \"Press enter to continue.\"; read;'"

# reload settings
bind-key R source-file ~/.tmux.conf

# Prevent terminal freezing by C-s
bind-key -n C-s display 'Terminal freezing by C-s prevented'

# -----------------------------
# Statusbar settings
# -----------------------------

# use vi-style key bindings in the status line
set -g status-keys vi

# amount of time for which status line messages and other indicators
# are displayed. time is in milliseconds.
set -g display-time 2000

# default statusbar colors
set -g status-style fg=white,bg=default

# default window title colors
set -g window-status-style fg=white,bg=default,dim

# active window title colors
set -g window-status-current-style fg=cyan,bg=default,bright,underscore

# command/message line colors
set -g message-style fg=white,bg=black,bright

# what to be displayed on the right status
set -g status-interval 1
set -g status-right ' } %Y-%m-%d %H:%M:%S'
set -g status-right-length 60

# what to be displayed on the left status
set -g status-left-length 30
set-option -g status-left "#[fg=green]#(echo $USER)#[default].#[fg=blue]#h#[default] { "

# -----------------------------
# Platform fix
# -----------------------------

# keep PATH for subprocess
run-shell 'tmux setenv -g TMUX_PATH $PATH'

# -----------------------------
# Multiple sessions detection
# -----------------------------

MULTIPLE_SESSION_WARN='display-message -p "=== WARN ===" ; \
  display-message -p "  Multiple tmux sessions detected," ; \
  display-message -p "  environment variables are from the first session" ;'
CHECK_MULTIPLE_SESSION="if-shell -b '[ $(tmux list-sessions | wc -l) -gt 1 ]' '${MULTIPLE_SESSION_WARN}'"
set-hook -g session-created ${CHECK_MULTIPLE_SESSION}