tmux-stare @ 4443c84cd1bb7bdfb96953a1b820145f10553e20

#!/usr/bin/env bash

CURRENT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

source "$CURRENT_DIR/helpers.sh"

declare S=$'\t'

# === common

get_current_session_name() {

  if [ "$(tmux display-message -p "#{session_grouped}")" = 0 ]; then

    tmux display-message -p "#{session_name}" 2>/dev/null || true

  else

    tmux display-message -p "#{session_group}" 2>/dev/null || true

  fi

}

rename_session() {

  local old="$1"

  local new="$2"

  local dir="$(get_opt_dir)"

  [[ -z "$old" || -z "$new" || "$old" == "$new" ]] && return 1

  [[ -e "$(get_opt_dir)/${new}_last" ]] && return 1

  tmux has-session -t "$new" 2>/dev/null && return 1

  tmux rename-session -t "$old" "$new" 2>/dev/null

  local old_last="${dir}/${old}_last"

  [[ -L "$old_last" ]] && {

    local actual="$(readlink "$old_last")"

    local new_actual="${dir}/${new}_$(basename "$actual" | cut -d_ -f2-)"

    mv "$actual" "$new_actual"

    ln -sf "$new_actual" "${dir}/${new}_last"

    rm "$old_last"

  }

}

# === save

save_cwd() {

  local session_name="$1"

  local save_file="$2"

  tmux display-message -p -t "$session_name" -F "#{session_path}" >>"$save_file"

}

save_windows() {

  local session_name="$1"

  local save_file="$2"

  local format="window$S#{window_index}$S#{window_name}$S#{window_layout}$S#{window_active}"

  tmux list-windows -t "$session_name" -F "$format" >>"$save_file"

}

format_process_command() {

  local pid="$1"

  [[ -r "/proc/${pid}/cmdline" ]] || return 1

  xargs -0 bash -c 'printf "%q " "$0" "$@"' <"/proc/${pid}/cmdline" 2>/dev/null | sed 's/[[:space:]]*$//'

}

get_descendant_pids() {

  local root_pid="$1"

  local proc_table

  local -A seen

  local frontier

  [[ -n "$root_pid" ]] || return 1

  proc_table="$(ps -ao ppid=,pid= --sort=pid)"

  frontier="$root_pid"

  seen["$root_pid"]="1"

  while [[ -n "$frontier" ]]; do

    local next_frontier=""

    local ppid

    local pid

    while read -r ppid pid; do

      local parent

      for parent in $frontier; do

        [[ "$ppid" == "$parent" ]] || continue

        [[ -n "${seen[$pid]:-}" ]] && continue

        seen["$pid"]="1"

        printf "%s\n" "$pid"

        next_frontier+=" $pid"

      done

    done <<<"$proc_table"

    frontier="${next_frontier# }"

  done

}

get_process_name() {

  local pid="$1"

  local first_arg

  [[ -r "/proc/${pid}/cmdline" ]] || return 1

  first_arg="$(tr '\0' '\n' <"/proc/${pid}/cmdline" 2>/dev/null | head -n1)"

  [[ -n "$first_arg" ]] || return 1

  basename "$first_arg"

}

select_active_command_pid() {

  local pane_pid="$1"

  local pane_target="$2"

  local pane_current_command

  local pids

  local pid

  local name

  local matching_pid=""

  local fallback_pid=""

  local descendant_count=0

  pane_current_command="$(tmux display-message -p -t "$pane_target" "#{pane_current_command}" 2>/dev/null)"

  pids="$(get_descendant_pids "$pane_pid")"

  for pid in $pids; do

    descendant_count=$((descendant_count + 1))

    fallback_pid="$pid"

    [[ -n "$pane_current_command" ]] || continue

    name="$(get_process_name "$pid")" || continue

    [[ "$name" == "$pane_current_command" ]] && matching_pid="$pid"

  done

  if [[ -n "$matching_pid" ]]; then

    printf "%s" "$matching_pid"

  elif [[ "$descendant_count" == "1" ]]; then

    printf "%s" "$fallback_pid"

  fi

}

capture_running_command() {

  local pane_pid="$1"

  local pane_target="$2"

  local command_pid

  command_pid="$(select_active_command_pid "$pane_pid" "$pane_target")"

  [[ -n "$command_pid" ]] || return 1

  format_process_command "$command_pid"

}

save_panes() {

  local session_name="$1"

  local save_file="$2"

  local format="pane$S#{pane_index}$S#{pane_current_path}$S#{pane_active}$S#{window_index}$S#{pane_pid}"

  tmux list-panes -s -t "$session_name" -F "$format" |

    while IFS="$S" read -r line; do

      local pane_target

      local command

      IFS="$S" read -r _ pane_index _ _ window_index pane_pid <<<"$line"

      pane_target="${session_name}:${window_index}.${pane_index}"

      command="$(capture_running_command "$pane_pid" "$pane_target")"

      awk -v command="$command" \

        'BEGIN {FS=OFS="\t"} {$6=command; print}' \

        <<<"$line" >>"$save_file"

    done

}

link_session_last() {

  local save_file="$1"

  local last_file="$2"

  if ! cmp -s "$save_file" "$last_file"; then

    ln -sf "$save_file" "$last_file"

  else

    rm "$save_file"

  fi

}

link_last() {

  local save_file="$1"

  local save_dir="$2"

  ln -sf "$save_file" "$save_dir"/last

}

save_session() {

  local session_name="$1"

  local save_dir="$(get_opt_dir)"

  local save_file="${save_dir}/${session_name}_$(get_time)"

  local last_file="${save_dir}/${session_name}_last"

  save_cwd "$session_name" "$save_file"

  save_windows "$session_name" "$save_file"

  save_panes "$session_name" "$save_file"

  link_session_last "$save_file" "$last_file"

  link_last "$last_file" "$save_dir"

}

save_all_sessions() {

  tmux list-sessions -F "#{session_name}" | while read -r session; do

    save_session "$session"

  done

  local current_session="$(get_current_session_name)"

  if [[ -n "$current_session" ]]; then

    link_last "$(get_opt_dir)/${current_session}_last" "$(get_opt_dir)"

  fi

}

unload_session() {

  local session_name="$1"

  save_session "$session_name"

  tmux kill-session -t "$session_name"

}

# === restore

restore_pane_processes_enabled() {

  local processes="$(get_opt_processes)"

  [[ "$processes" != "false" ]]

}

restore_all_processes() {

  local processes="$(get_opt_processes)"

  [[ "$processes" == ":all:" ]]

}

restore_list() {

  get_opt_processes

}

get_proc_match_element() {

  local proc="$1"

  printf "%s" "${proc%%->*}"

}

proc_matches_command() {

  local command="$1"

  local match="$2"

  if [[ "${match:0:1}" == "~" ]]; then

    local relaxed="${match#~}"

    [[ "$command" == *"$relaxed"* ]]

  else

    [[ "$command" == "$match" || "$command" == "$match "* ]]

  fi

}

command_on_restore_list() {

  local command="$1"

  local proc

  local match

  local restore_list_value

  restore_list_value="$(restore_list)"

  # shellcheck disable=SC2086

  eval "set -- $restore_list_value"

  for proc in "$@"; do

    match="$(get_proc_match_element "$proc")"

    if proc_matches_command "$command" "$match"; then

      return 0

    fi

  done

  return 1

}

should_restore_command() {

  local command="$1"

  [[ -z "$command" ]] && return 1

  restore_pane_processes_enabled || return 1

  restore_all_processes && return 0

  command_on_restore_list "$command"

}

restore_session_from_file() {

  local session_file="$1"

  local session_name=$(basename "$session_file" | sed 's/_last$//')

  exec <"$session_file"

  start_spinner "Restoring session $session_name"

  local session_path="$(head -n1)"

  [[ -n "$session_path" ]] || session_path="$HOME"

  tmux new-session -ds "$session_name" -c "$session_path"

  declare -A window_layouts

  declare active_window

  while read -r line; do

    case $line in

    window*)

      IFS=$S read -r _ window_index window_name window_layout window_active <<<"$line"

      window_id="$session_name:$window_index"

      tmux new-window -k -t "$window_id" -n "$window_name"

      window_layouts["$window_id"]="$window_layout"

      if [[ "$window_active" == "1" ]]; then

        active_window="$window_id"

      fi

      ;;

    pane*)

      IFS=$S read -r _ pane_index pane_current_path pane_active window_index command <<<"$line"

      if [[ "$pane_index" == "$(get_tmux_option base-index 0)" ]]; then

        tmux send-keys -t "$session_name:$window_index" "cd \"$pane_current_path\"" Enter "clear" Enter

      else

        tmux split-window -d -t "$session_name:$window_index" -c "$pane_current_path"

      fi

      if [[ "$pane_active" == "1" ]]; then

        tmux select-pane -t "$session_name:$window_index.$pane_index"

      fi

      if should_restore_command "$command"; then

        tmux send-keys -t "$session_name:$window_index.$pane_index" "$command" Enter

      fi

      ;;

    esac

  done

  for window in "${!window_layouts[@]}"; do

    tmux select-layout -t "$window" "${window_layouts[$window]}"

  done

  tmux select-window -t "$active_window"

  tmux switch-client -t "$session_name"

  stop_spinner "Session restored"

}

restore_session() {

  local session_name="$1"

  if tmux has-session -t "$session_name" 2>/dev/null; then

    tmux switch-client -t "$session_name"

    return 0

  fi

  local session_file="$(get_opt_dir)/${session_name}_last"

  if [[ ! -f "$session_file" ]]; then

    tmux display-message "No saved session found for: $session_name"

    return 1

  fi

  restore_session_from_file "$session_file"

}

restore_last() {

  local last_file="$(get_opt_dir)/last"

  if [[ ! -e "$last_file" ]]; then

    tmux display-message "No last session saved"

    return 1

  fi

  local session_name=$(basename "$(readlink "$last_file")" | sed 's/_last$//')

  restore_session "$session_name"

}