improve emacs/bash integration

1 files changed, 96 insertions, 39 deletions

diff --git a/.config/bash/rc.d/emacs.sh b/.config/bash/rc.d/emacs.sh
index 9c1bf4d..165d71e 100644
--- a/.config/bash/rc.d/emacs.sh
+++ b/.config/bash/rc.d/emacs.sh
@@ -1,41 +1,98 @@
 #!/bin/bash
 
-case "$TERM" in
-	eterm*)
-		SELECTED_EDITOR='emacsclient'
-		EDITOR=$SELECTED_EDITOR
-		VISUAL=$SELECTED_EDITOR
-		export SELECTED_EDITOR EDITOR VISUAL
-		# The following uses the variable _EMACS_BUFFER to store some state
-		_emacs_quote() {
-			local str="$*"
-			str="${str//\\/\\\\}"
-			str="${str//\"/\\\"}"
-			str="\"${str}\""
-			printf '%s' "$str"
-		}
-		_emacs_rename_terminal() {
-			local name="$(_emacs_quote "$(_emacs_get_desired_buffer_name)")"
-			if [[ -n $_EMACS_BUFFER ]]; then
-				local buffer="(get-buffer $_EMACS_BUFFER)"
-			else
-				local buffer='(window-buffer (selected-window))'
-			fi
-			_EMACS_BUFFER="$(emacsclient -e "(with-current-buffer ${buffer} (rename-buffer ${name} t)))" 2>/dev/null)"
-		}
-		_emacs_get_short_cwd() {
-			local base=$1
-			local suffix=''
-			if [[ $base =~ (/(src|pkg|doc|pkg-libre|src-libre|trunk|tags|branches))*$ ]]; then
-				suffix=$BASH_REMATCH
-				base=${base%$suffix}
-			fi
-			base=${base##*/}
-			echo ${base}${suffix}
-		}
-		_emacs_get_desired_buffer_name() {
-			echo "*ansi-term*<$(_emacs_get_short_cwd "$PWD")>"
-		}
-		PROMPT_COMMAND='_emacs_rename_terminal "$(_emacs_get_desired_buffer_name)"'
-		:;;
-esac
+if [[ $TERM == eterm* ]]; then
+	SELECTED_EDITOR='emacsclient'
+	EDITOR=$SELECTED_EDITOR
+	VISUAL=$SELECTED_EDITOR
+	export SELECTED_EDITOR EDITOR VISUAL
+
+	## Primatives for interacting with Emacs ###############################
+
+	# _emacs_run LISP
+	_emacs_run() {
+		emacsclient -e "$*" 2>/dev/null
+	}
+	# _emacs_quote UNQUOTED_STRING
+	_emacs_quote() {
+		local str="$*"
+		str="${str//\\/\\\\}" # \ -> \\
+		str="${str//\"/\\\"}" # " -> \"
+		str="\"${str}\""      # wrap it in quotes
+		printf '%s' "$str"
+	}
+	# _emacs_unquote QUOTED_STRING
+	_emacs_unquote() {
+
+		local str="$*"
+		if [[ $str =~ ^\"(.*)\"$ ]]; then
+			str=${BASH_REMATCH[1]} # un-quote it
+			str="${str//\\\\/\\}" # \\ -> \
+			str="${str//\\\"/\"}" # \" -> "
+		fi
+		printf '%s' "$str"
+	}
+
+	## Deal with renaming the terminal #####################################
+
+	# _emacs_rename_terminal NEW_BUFFER_NAME
+	# This function uses the variable _EMACS_BUFFER to store some state
+	_emacs_rename_terminal() {
+		local name=$(_emacs_quote "$*")
+		if [[ -n $_EMACS_BUFFER ]]; then
+			local buffer="(get-buffer $_EMACS_BUFFER)"
+		else
+			local buffer='(window-buffer (selected-window))'
+		fi
+		_EMACS_BUFFER=$(_emacs_run "(with-current-buffer ${buffer} (rename-buffer ${name} t))")
+	}
+	# _emacs_get_short_cwd
+	_emacs_get_short_cwd() {
+		local base=$PWD
+		local suffix=''
+		# The regex here is a list of directory names
+		# that aren't really helpful, and that the
+		# parent directory should be included also.
+		if [[ $base =~ (/(src|pkg|doc|pkg-libre|src-libre|trunk|tags|branches))*$ ]]; then
+			suffix=$BASH_REMATCH
+			base=${base%$suffix}
+		fi
+		base=${base##*/}
+		echo ${base}${suffix}
+	}
+	# _emacs_get_desired_buffer_name
+	_emacs_get_desired_buffer_name() {
+		echo "*ansi-term*<$(_emacs_get_short_cwd)>"
+	}
+
+	## High-level tasks ####################################################
+
+	# Like uniquify on the buffer name (shell -> emacs)
+	_emacs_set_buffer_name() {
+		# This doesn't work correctly on remote hosts.
+		# The "correct" solution is probably to hook into
+		# default-directory being set in term.el
+		_emacs_rename_terminal "$(_emacs_get_desired_buffer_name)"
+	}
+	# Set the TRAMP directory for remote hosts (shell -> emacs)
+	_emacs_set_remote_dir() {
+		if [[ -n $SSH_CONNECTION ]]; then
+			printf '\eAnSiT%s %s\n' \
+				u "$USER" \
+				c "$PWD" \
+				h "$HOSTNAME"
+		fi
+	}
+	# Set the shell's X11 display (emacs -> shell)
+	_emacs_set_shell_DISPLAY() {
+		export DISPLAY=$(_emacs_unquote "$(_emacs_run "(cdr (assoc 'display (frame-parameters)))")")
+	}
+
+	## Do those things #####################################################
+
+	_emacs_PROMPT_COMMAND() {
+		_emacs_set_buffer_name
+		_emacs_set_remote_dir
+		_emacs_set_shell_DISPLAY
+	}
+	PROMPT_COMMAND=_emacs_PROMPT_COMMAND
+fi