/*  $Id$

    Part of XPCE --- The SWI-Prolog GUI toolkit

    Author:        Jan Wielemaker and Anjo Anjewierden
    E-mail:        jan@swi.psy.uva.nl
    WWW:           http://www.swi.psy.uva.nl/projects/xpce/
    Copyright (C): 1985-2002, University of Amsterdam

    This program is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public License
    as published by the Free Software Foundation; either version 2
    of the License, or (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    As a special exception, if you link this library with other files,
    compiled with a Free Software compiler, to produce an executable, this
    library does not by itself cause the resulting executable to be covered
    by the GNU General Public License. This exception does not however
    invalidate any other reasons why the executable file might be covered by
    the GNU General Public License.
*/

:- module(emacs_shell_mode,
	  []).
:- use_module(library(pce)).
:- require([ between/3
	   , default/3
	   , forall/2
	   , ignore/1
	   ]).


:- pce_begin_class(emacs_process_buffer, emacs_buffer).

variable(process,	   process*,	get,	"Associated process").
variable(process_fragment, fragment,	get,	"Process' insertion point").
variable(prompt_regex,     regex*,	both,	"Regex for prompt").
variable(history,	   chain,	get,	"Chain of commands send").

delegate_to(process).

class_variable(prompt_regex, regex*, @nil, "Default prompt").

initialise(B, Process:[process]*, Name:[name]) :->
	"Create from process and name"::
	(   Name == @default
	->  new(BufName, string('*%s*', Process?name))
	;   BufName = Name
	),

	send(B, send_super, initialise, @nil, BufName),
	send(B, slot, process_fragment, fragment(B, 0, 0)),
	send(B, slot, history, new(chain)),
	send(B, mode, shell),
	(   Process \== @default
	->  send(B, process, Process)
	;   true
	),
	send(B, obtain_class_variables).


unlink(B) :->
	"Kill the process"::
	get(B, process, P),
	(   P \== @nil
	->  send(P, free)
	;   true
	),
	send(B, send_super, unlink).


lookup(_Ctx, Process:[process]*, Name:name, Buffer:emacs_buffer) :<-
	"Reuse named buffer"::
	get(@emacs_buffers, member, Name, DictItem),
	get(DictItem, object, Buffer),
	send(Buffer, instance_of, emacs_process_buffer),
	(   Process \== @default
	->  send(Buffer, clear),
	    send(Buffer, process, Process)
	;   true
	).



		 /*******************************
		 *	       LABEL		*
		 *******************************/

modified(_B, _Val:bool) :->
	"Just succeed"::
	true.


update_label(B) :->
	"Update label in the buffer-menu"::
	get(B, name, Name),
	get(B, process, Process),
	(   Name \== @nil,
	    Process \== @nil
	->  get(Process, status, Status),
	    map_status(Status, Indicator),
	    get(@emacs_buffers, member, Name, DictItem),
	    send(DictItem, label, string('%s\t%s', Name, Indicator)),
	    new(FrameLabel, string('%s [%s]', Name, Status)),
	    send(B?editors, for_all,
		 message(@arg1?frame, label, FrameLabel))
	;   true
	).

map_status(running, 'R').
map_status(stopped, 'Z').
map_status(killed,  'K').
map_status(exited,  'Done').
map_status(_,       '??').


		 /*******************************
		 *          THE PROCESS		*
		 *******************************/

process(B, Process:process*) :->
	"Associate process with buffer"::
	(   get(B, process, OldProcess),
	    OldProcess \== @nil
	->  send(OldProcess, free)
	;   true
	),
	send(B, slot, process, Process),
	send(Process, attribute, report_to, B),
	get(B, process_fragment, Fragment),
	send(Fragment, start, B?size),
	send(Fragment, length, 0),
	(   Process \== @nil
	->  send(Process, record_separator, @nil),
	    send(Process, input_message,
		 message(B, insert_process_input, @arg1)),
	    send(Process, terminate_message,
		 message(B, terminated, @arg1)),
	    send(Process, environment, 'TERM', emacs),
	    ignore(send(Process?environment, delete, 'TERMCAP')),
	    send(Process, environment, 'INFERIOR', yes),
	    send(B, update_label)
	;   true
	).


insert_process_input(B, Input:string) :->
	send(Input, translate, 13, @nil),     % delete \r's (fixed in process)
	get(B, process_fragment, Fragment),
	send(Fragment, insert, @default, Input).


terminated(B, Code:'name|int') :->
	"Indicate proces terminated"::
	(   atom(Code)
	->  send(B, report, warning, 'Terminated on signal %s at %s',
		 Code, @pce?date)
	;   Code == 0
	->  send(B, report, status, 'Finished at %s', @pce?date)
	;   send(B, report, warning, 'Exited status %s at %s',
		 Code, @pce?date)
	),
	send(B, update_label).



		 /*******************************
		 *        SENDING INPUT		*
		 *******************************/

:- pce_global(@newline, new(string('\n'))).

send_input(B, Caret:int) :->
	"Send data from the process input"::
	get(B, process_fragment, Fragment),
	get(Fragment, end, End),
	(   Caret >= End
	->  get(B, contents, End, Caret-End, Data),
	    send(B, insert, Caret, @newline)
 	;   get(B, scan, Caret, line, 0, start, SOL),
	    get(B, scan, Caret, line, 0, end, EOL),
	    get(B, contents, SOL, EOL-SOL, Data),
	    (   get(B, prompt_regex, Prompt), Prompt \== @nil,
		get(Prompt, match, Data, Size)
	    ->  send(Data, delete, 0, Size)
 	    ;   true
 	    ),
	    send(B, append, Data),
	    send(B, append, @newline),
	    send(B?editors, for_all, message(@arg1, caret))
	),
	get(B, size, Size),
	send(Fragment, start, Size),
	send(Fragment, length, 0),
	(   get(Data, size, 0)
	->  send(Data, newline)
	;   send(Data, ensure_nl)
	),
	new(H, string('%s', Data)),
	send(H, strip),
	(   \+ send(H, equal, '')
	->  send(B?history, prepend, H)
	;   true
	),
	(   pce_catch_error(not_open,
			    send(B?process, append, Data))
	->  true
	;   send(B, report, warning, 'No process')
	).


format_data(B, Fmt:char_array, Args:any...) :->
	"Send formatted data to process"::
	StringTerm =.. [string,Fmt|Args],
	new(S, StringTerm),
	send(B, append, S),
	get(B, size, Size),
	send(B?editors, for_some, message(@arg1, caret, Size)),
	get(B, process_fragment, Fragment),
	send(Fragment, start, Size),
	send(Fragment, length, 0),
	send(B?process, append, S).


		 /*******************************
		 *        EDIT OPERATIONS	*
		 *******************************/

clear(B) :->
	"->clear, but reinsert ->process_fragment"::
	send(B, send_super, clear),
	send(B?history, clear),
	send(B, slot, process_fragment, fragment(B, 0, 0)).


kill(B) :->
	"Kill buffer and process"::
	get(B, process, Process),
	(   get(Process, pid, Pid), Pid \== @nil
	->  new(D, dialog('Kill running process buffer?')),
	    send(D, append, new(L, label(reporter))),
	    send(L, format, 'Process is running'),
	    send(D, append,
		 button(kill, message(D, return, kill))),
	    send(D, append,
		 button(cancel, message(D, return, cancel))),
	    get(D, confirm_centered, Rval),
	    send(D, destroy),
	    (	Rval == kill
	    ->	send(B, free)
	    ;	fail
	    )
	;   send(B, free)
	).


properties(B) :->
	get(B, properties, V),
	get(B, process, Process),
	send(V, appendf, 'Command:\t%s\n', Process?name),
	send(V, appendf, 'Arguments:\t'),
	get(Process, arguments, Argv),
	get(Argv, size, Size),
	(   Size == 0
	->  send(V, appendf, '<none>')
	;   get(Argv, element, 1, A1),
	    send(V, appendf, '%s', A1),
	    forall(between(2, Size, AN),
		   send(V, appendf, ' %s', ?(Argv, element, AN)))
	),
	send(V, appendf, '\n'),
	send(V, appendf, 'Status:\t%s\n', Process?status).


		 /*******************************
		 *      WINDOW INTERFACE	*
		 *******************************/

start_process(B) :->
	"Start process if not running"::
	(   get(B, process, Process), Process \== @nil
	->  send(Process, open),
	    send(B, update_label)
	;   send(B, report, warning, 'No process')
	).


open(B, New:[bool]) :->
	"Create window for buffer"::
	(   New == @on
	->  send(new(Window, emacs_frame(B)), open)
	;   (	\+ send(B?editors, empty)
	    ->	send(B?editors?head?frame, expose)
	    ;	get(@emacs, free_window, B?pool, Window)
	    ->	send(Window, buffer, B)
	    ;	send(emacs_frame(B), open)
	    )
	),
	(   nonvar(Window)
	->  send(Window?editor, caret, @default)
	;   true
	),
	send(B, update_label).


:- pce_end_class.


		 /*******************************
		 *         SHELL MODE		*
		 *******************************/

:- pce_begin_class(emacs_shell_mode, emacs_fundamental_mode).

:- initialization
	new(KB, emacs_key_binding(shell, fundamental)),
	send(KB, function, 'RET', send_input),
	send(KB, function, '\\C-c\\C-c', interrupt_subjob),
	send(KB, function, '\\C-c\\C-d', end_of_file),
	send(KB, function, '\\C-c\\C-h', show_history),
	send(KB, function, '\\ep',      backward_history),
	send(KB, function, '\\en',      forward_history),
	send(KB, function, '\\C-cRET',  mark_errors),
	send(KB, function, '\\C-c\\C-f', visit_file),
	send(KB, function, '\\C-c\\C-e', goto_error),
	send(KB, function, '\\C-c\\C-\\', quit_subjob),
	send(KB, function, '\\C-c\\C-k', kill_subjob).

:- initialization
	new(T, syntax_table(shell)),
	send(T, syntax, '.', symbol),
	send(T, syntax, '-', symbol),
	send(T, syntax, '"', string_quote, '\\'),
	send(T, syntax, '''', string_quote, '\\').

:- initialization
	new(MM, emacs_mode_menu(shell, fundamental)),
	send(MM, append, shell, start_process),
	send(MM, append, shell, goto_error),
	send(MM, append, shell, mark_errors),
	send(MM, append, shell, visit_file),

	send(MM, append, shell, end_of_file),
	send(MM, append, shell, interrupt),
	send(MM, append, shell, kill_subjob).


variable(current_history, number*, both, "Current history number").

:- pce_global(@event_mode, new(@event?receiver?window?editor?mode)).

process(E, P:process) :<-
	"Process object associated with editor"::
	get(E, text_buffer, TB),
	send(TB, instance_of, emacs_process_buffer),
	get(TB, process, P),
	(   get(P, pid, Pid), Pid \== @nil
	->  true
	;   send(E, report, error, 'No process'),
	    fail
	).


		 /*******************************
		 *        SENDING INPUT		*
		 *******************************/

send_input(E) :->
	"Send data to process"::
	send(E, end_of_line),
	send(E?text_buffer, send_input, E?caret).


		 /*******************************
		 *	       EDIT		*
		 *******************************/

beginning_of_line(E, Lines:[int]) :->
	"Move to start of input"::
	(   Lines == @default,
	    get(E, caret, Caret),
	    get(E, text_buffer, B),
	    get(B, scan, Caret, line, 0, start, SOL),
	    get(B, process_fragment, Fragment),
	    get(Fragment, end, End),
	    Caret >= End,
	    SOL =< Caret
	->  send(E, caret, End)
	;   send(E?editor, beginning_of_line, Lines)
	).


clear(E) :->
	"Clear process buffer"::
	get(E, text_buffer, TB),
	send(TB, clear).

		 /*******************************
		 *	     HISTORY		*
		 *******************************/

show_history(E, N:[int]) :->
	"Show last N commands"::
	default(N, 10, Cmds),
	get(E, text_buffer, TB),
	get(E, caret, Caret),
	get(TB, scan, Caret, line, 0, start, SOL),
	get(TB, contents, SOL, Caret-SOL, Prompt),
	get(TB, history, Chain),
	insert_history(Cmds, Chain, E),
	send(E, format, '\n%s', Prompt),
	get(TB, process_fragment, Frag),
	send(Frag, end, E?caret).

insert_history(0, _, _) :- !.
insert_history(N, Chain, E) :-
	(   get(Chain, nth1, N, Data)
	->  send(E, format, '\n\t%s', Data)
	;   true
	),
	NN is N - 1,
	insert_history(NN, Chain, E).


backward_history(E, Id:event_id) :->
	"Insert last command"::
	send(E, current_history, 0),
	send(E, focus_function, '_history'),
	send(E, '_history', Id).


'_history'(E, Id:event_id) :->
	get(E?bindings, function, Id, Func),
	get(E, text_buffer, B),
	get(B, history, Chain),

	get(E, current_history, Current),
	(   Func == backward_history
	->  send(Current, plus, 1)
	;   Func == forward_history
	->  send(Current, minus, 1)
	),

	get(B, process_fragment, Frag),
	get(Frag, end, End),
	send(E, caret, End),
	get(B, size, Size),
	send(B, delete, End, Size),

	(   get(Chain, nth1, Current, Data)
	->  send(B, insert, End, Data)
	;   send(E, report, status, 'No (more) history')
	).

		 /*******************************
		 *           SIGNALS		*
		 *******************************/

kill_subjob(E, Signal:'[int|name]') :->
	"Send signal to shell"::
	send(E?process, kill, Signal).

interrupt_subjob(E) :->
	"Send control-C to process"::
	send(E?process, append, string('%c', 3)).	% ^C

quit_subjob(E) :->
	"Send control-\ to process"::
	send(E?process, append, string('%c', 28)).	% ^\

suspend_subjob(E) :->
	"Send control-Z to process"::
	send(E?process, append, string('%c', 26)).	% ^Z

end_of_file(E) :->
	"Send control-D to process"::
	send(E?process, append, string('%c', 4)).	% ^D


		 /*******************************
		 *	  FINDING ERRORS	*
		 *******************************/

:- pce_global(@emacs_error_regexs,
	      new(chain(regex('(\\S+):\\s*(\\d+):'),        % gcc, grep
			regex('"(\\S+)", line (\\d+):')))). % SUN cc
:- pce_global(@emacs_cd_regexs,
	      new(chain(regex('\\ycd\\s+((\\w|[_/+-.:])+)'),
			regex('Entering directory `([^\']+)\'')))).
:- pce_global(@emacs_canonise_dir_regex,
	      new(regex('[^/]+/\\.\\./'))).

canonise_path(Path) :-
	send(regex('[^/]+/\\.\\./'), for_all, Path,
	     message(@arg1, replace, Path, '')),
	send(regex('/\\./|//'), for_all, Path,
	     message(@arg1, replace, Path, '/')).

directory_name(M, Pos:[int]*, DirName:string) :<-
	"New string with Directory at position"::
	get(M, text_buffer, TB),
	(   Pos == @nil
	->  get(TB, directory, Dir),
	    new(DirName, string('%s', Dir?path))
	;   (	Pos == @default
	    ->	get(M, caret, P0)
	    ;	P0 = Pos
	    ),
	    (	match_cd_regex(TB, P0, Dir0, Here)
	    ->  (   send(file(Dir0), is_absolute)
		->  DirName = Dir0
		;   get(M, directory_name, Here, DirName),
		    send(DirName, ensure_suffix, /),
		    send(DirName, append, Dir0)
		)
	    ;	get(M?text_buffer, directory, Dir),
		new(DirName, string('%s', Dir?path))
	    )
	),
	send(DirName, ensure_suffix, /),
	canonise_path(DirName).


match_cd_regex(TB, P0, Dir, Here) :-
	get(@emacs_cd_regexs, find_all,
	    message(@arg1, search, TB, P0, 0), Hits),
	send(Hits, sort,
	     ?(@arg2?register_start, compare, @arg1?register_start)),
	get(Hits, head, Regex),
	get(Regex, register_start, Here),
	get(Regex, register_value, TB, 1, Dir),
	send(Hits, done).


directory(M, Pos:[int]*, Dir:directory) :<-
	"Current working directory"::
	get(M, directory_name, Pos, DirName),
	new(Dir, directory(DirName)).


error(M, Pos:int, Tuple:tuple) :<-
	"FileName and line number from error"::
	get(M, text_buffer, TB),
	get(TB, scan, Pos, line, 0, start, SOL),
	get(TB, scan, Pos, line, 0, end, EOL),
	get(@emacs_error_regexs, find,
	    message(@arg1, search, TB, SOL, EOL), Regex),
	get(Regex, register_value, TB, 1, R1),
	get(Regex, register_value, TB, 2, R2),
	(   get(@pce, convert, R1, int, LineNo)
	->  get(R2, value, File)
	;   get(@pce, convert, R2, int, LineNo)
	->  get(R1, value, File)
	;   send(M, report, warning, 'No line number in error'),
	    fail
	),
	(   send(File, prefix, /)
	->  new(Tuple, tuple(File, LineNo))
	;   get(M, directory_name, SOL, DirNameStr),
	    send(DirNameStr, append, File),
	    canonise_path(DirNameStr),
	    get(DirNameStr, value, DirName),
	    new(Tuple, tuple(DirName, LineNo))
	).


mark_errors(M, From:[int], To:[int]) :->
	"Mark errors in range using fragments"::
	send(M, report, status, 'Marking errors ...'),
	get(M, text_buffer, TB),
	default(From, 0, F0),
	default(To, TB?size, T),
	get(TB, scan, F0, line, 0, start, F1),
	new(Here, number(F1)),
	new(Errors, number(0)),
	repeat,
	     (	 get(M, error, Here, tuple(File, Line))
	     ->	 new(B, emacs_buffer(File)),
		 get(B, scan, 0, line, Line-1, start, SOF),
		 get(B, scan, SOF, line, 0, end, EOF),
		 new(FThere, emacs_link_fragment(B, SOF, EOF-SOF)),
		 get(TB, scan, Here, line, 0, end, EOL),
		 new(FHere, emacs_link_fragment(TB, Here, EOL-Here)),
		 send(FHere, link, FThere),
		 send(Errors, plus, 1)
	     ;	 true
	     ),
	     get(TB, scan, Here, line, 1, start, NewHere),
	     (	 send(T, larger, NewHere)
	     ->	 send(Here, value, NewHere),
		 fail
	     ;	 !,
	         (   send(Errors, larger, 0)
		 ->  send(M, report, status, 'Marked %d errors', Errors)
		 ;   send(M, report, status, 'No errors')
		 )
	     ).


goto_error(M) :->
	"Goto error from current_line"::
	get(M, caret, Caret),
	(   get(M, find_fragment,
		and(message(@arg1, instance_of, emacs_link_fragment),
		    message(@arg1, overlap, Caret)),
		Fragment)
	->  send(Fragment, follow)
	;   get(M, error, Caret, tuple(File, Line))
	->  new(B, emacs_buffer(File)),
	    send(B, open),
	    send(B?editors?head, line_number, Line)
	;   send(M, report, warning, 'No error on this line')
	).

visit_file(M) :->
	"Visit file from the caret"::
	get(M, word, FileName),
	get(M, directory_name, M?caret, Dir),
	send(Dir, append, FileName),
	new(F, file(Dir)),
	(   send(F, exists)
	->  new(B, emacs_buffer(F)),
	    send(B, open)
	;   send(M, report, error, '%s: no such file', Dir),
	    fail
	).

:- pce_end_class.


		 /*******************************
		 *	 LINKED FRAGMENTS	*
		 *******************************/

:- pce_begin_class(emacs_link_fragment, fragment,
		   "Pair of linked fragments").

variable(link,		fragment,	get,	"Fragment I'm linked to").

unlink(F) :->
	"Remove fragment and 'linked-to'"::
	get(F, link, F2),
	(   F2 \== @nil
	->  send(F, slot, link, @nil),
	    free(F2)
	;   true
	),
	send(F, send_super, unlink).


link(F, F2:emacs_link_fragment) :->
	send(F, slot, link, F2),
	send(F2, slot, link, F).


follow(F) :->
	"Goto other end of link"::
	get(F, link, F2),
	get(F2, text_buffer, B),
	send(B, open),
	send(B?editors?head, caret, F2?start).

:- pce_end_class.
