.bindrc

# vim: ft=sh
#
# ~/.bindrc
#
# shellcheck disable=SC2016,SC2064,SC2086

# Attempt to perform completion on the text before point
bind -m vi-command  '"\t":   complete'
bind -m vi-insert   '"\t":   complete'

# Perform history expansion on the current line
bind -m vi-command  '"\ef":  history-expand-line'
bind -m vi-insert   '"\ef":  history-expand-line'
# Perform glob expansions
bind -m vi-command  '"\eg":  glob-expand-word'
bind -m vi-insert   '"\eg":  glob-expand-word'
# Perform shell word expansions
bind -m vi-command  '"\ee":  shell-expand-line'
bind -m vi-insert   '"\ee":  shell-expand-line'
# Perform spelling correction on the current word
bind -m vi-command  '"\ez":  spell-correct-word'
bind -m vi-insert   '"\ez":  spell-correct-word'

# Drag the word before point past the word after point
bind -m vi-command  '"\C-t": transpose-words'
bind -m vi-insert   '"\C-t": transpose-words'

# Clear screen
bind -m vi-command  '"\C-l": clear-screen'
bind -m vi-insert   '"\C-l": clear-screen'

# Provide a negative numeric argument
bind -m vi-command  '"-":    digit-argument'

# Move cursor to the end of line
bind -m vi-command  '"\C-e": end-of-line'
bind -m vi-insert   '"\C-e": end-of-line'

# Uppercase previous (or current) word with Ctrl-b
upcase-word() {
    local line word i j
    declare -r PATTERN='[a-zA-Z0-9_-]'
    line="$READLINE_LINE" # typed line
    i="$READLINE_POINT"   # cursor position
    j="$READLINE_POINT"
    # find index of the beginning of the word under cursor
    while ((i > 0)) && [[ "${line:${i}-1:1}" =~ $PATTERN ]]; do ((i--)); done
    # find index of the end of the word under cursor
    while [[ "${line:${j}:1}" =~ $PATTERN ]]; do ((j++)); done
    # word under cursor (start=i; length=j-i)
    word="${line:${i}:$((j - i))}"
    # combine: line before word, upper-cased word, line after word
    READLINE_LINE="${line:0:${i}}${word@U}${line: ${j}}"
}
bind -m vi-command -x '"\C-b": upcase-word'
bind -m vi-insert  -x '"\C-b": upcase-word'

# invoke the manual for the command preceding the cursor by pressing Alt-h.
run-help() {
    local tmp_line
    local tmp_line_start="${READLINE_LINE:0:READLINE_POINT}"
    local tmp_line_end="${READLINE_LINE:READLINE_POINT}"
    tmp_line="${tmp_line_start}${tmp_line_end%%[!A-Za-z0-9_]*}"
    tmp_line="${tmp_line##*|}"
    tmp_line="${tmp_line##*;}"
    tmp_line="${tmp_line##*\(}"

    local -a line
    read -ra line <<< "$tmp_line"
    if (( ${#line[@]} == 0 )); then
        return 1
    fi

    local -a pager_cmd
    if command -v bat >/dev/null 2>&1; then
        pager_cmd=(bat -plhelp --theme Spx)
    else
        pager_cmd=(less)
    fi

    local -a cmd1 cmd2 cmd3
    local -a help_cmd

    # shellcheck disable=SC2034
    if (( ${#line[@]} == 1 )); then
        cmd1=(help "${line[0]}")
        cmd2=("${line[0]}" --help)
        cmd3=("${line[0]}" -h)

        help_cmd=(cmd1 cmd2 cmd3)
    else
        cmd1=("${line[0]}" help "${line[@]:1}")
        cmd2=("${line[@]}" --help)

        help_cmd=(cmd1 cmd2)
    fi

    local cmd help_text lwid rwid lpad rpad

    for cmd in "${help_cmd[@]}"; do
        local -n args="$cmd"

        if help_text="$("${args[@]}" 2>/dev/null)"; then
            # Build the display label from the actual arguments.
            printf -v cmd '%q ' "${args[@]}"
            cmd=${cmd% }

            # if the screen is wide enough, add a padding to the title line
            if [[ -v COLUMNS ]] && ((COLUMNS - ${#cmd} > 4)); then
                ((lwid = (COLUMNS - ${#cmd}) / 2))
                ((rwid = COLUMNS - lwid - ${#cmd}))
                printf -v lpad '%*s' $((lwid - 2)) ''
                printf -v rpad '%*s' $((rwid - 2)) ''
                lpad="${lpad// /+}"
                rpad="${rpad// /+}"
            else
                lwid=1; rwid=1; lpad='+'; rpad='+'
            fi

            printf '%-*s%s%*s\n%s\n\n' \
                "$lwid" "$lpad" "$cmd" "$rwid" "$rpad" "$help_text" \
                | "${pager_cmd[@]}"
            return

        fi

        unset -n args
    done

    return 1
}
bind -m vi-command -x '"\eh": run-help'
bind -m vi-insert  -x '"\eh": run-help'
bind -m emacs      -x '"\eh": run-help'

# start ptpython with Alt-r
# https://github.com/termctrlseq/pt-live
start-ptpython() {
    local pt_prompt="\[\e[1;38;5;8m\][i]${PS1}\[\e[1;38;5;8m\]=> \[\e[0m\]"
    if [[ -v TMUX ]]; then
        tmux rename-window ptpy
    fi
    pt_live.py "${pt_prompt@P}"
    if [[ -v TMUX ]]; then
        tmux set-option automatic-rename on
    fi
}
bind -m vi-command -x '"\er": start-ptpython'
bind -m vi-insert  -x '"\er": start-ptpython'

# start auto completion menu with Alt-m
# https://github.com/termctrlseq/bash-auto-comp
bash-auto-comp() {
    local mode="" prompt cmd_file
    mode="\[\e[1;38;5;8m\][i]\[\e[0m\]"
    local -a result
    prompt="${mode}$(perl -pe 's/\\\[\\e\].*?\\\]//g' <<<"${PS1}")"
    cmd_file="$(mktemp)" || return
    trap 'rm -f "$cmd_file"' RETURN

    if bash_auto_comp.py "$cmd_file" "${prompt@P}" \
        && [[ -r "$cmd_file" ]]
    then
        mapfile -t result <"$cmd_file"
        if ((${#result[@]} == 2)); then
            READLINE_POINT="${result[0]}"
            READLINE_LINE="${result[1]}"
        fi
    fi
}
bind -m vi-command -x '"\em": bash-auto-comp'
bind -m vi-insert  -x '"\em": bash-auto-comp'