/*  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
    All rights reserved.

    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
    are met:

    1. Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.

    2. Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in
       the documentation and/or other materials provided with the
       distribution.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    POSSIBILITY OF SUCH DAMAGE.
*/

/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Toplevel file of the  XPCE/Prolog  dialog   window  editor.   This  file
defines the XPCE class dia_editor (subclass  of class frame), from which
you may create an instances and open them.

The dialog editor is normally started through  the file dialog.pl in the
standard XPCE library directory.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

:- module(dia_dialog, []).
:- use_module(library(pce)).
:- use_module(library(pce_prompter)).
:- [ proto,
     layout,
     generate,
     pretty_print,
     behaviour,
     load,
     util
   ].
:- use_module(library(pce_template)).
:- require([ between/3
           , default/3
           , forall/2
           , ignore/1
           , maplist/3
           , member/2
           , pce_help_file/2
           , pce_image_directory/1
           , postscript/2
           , send_list/3
           ]).


:- pce_autoload(drag_and_drop_gesture, library(dragdrop)).
:- pce_autoload(drag_and_drop_dict_item_gesture, library(dragdict)).
:- pce_autoload(dia_attribute_editor, library('dialog/attribute')).
:- pce_autoload(finder, library(find_file)).
:- pce_global(@finder, new(finder)).

dia_version('0.8').

:- dynamic
    paths_initialised/0.

initialise_paths :-
    paths_initialised,
    !.
initialise_paths :-
    pce_help_file(dialog, pce_help('dialog.hlp')),
    pce_image_directory(library('dialog/bitmaps')),
    assert(paths_initialised).


                 /*******************************
                 *        PROTO TEMPLATE        *
                 *******************************/

:- pce_begin_class(dia_proto, template).

variable(can_resize,      bool := @off, both,   "Object can be resized").
variable(proto,           name,         both,   "Name of proto description").
variable(ref_indicator,   graphical*,   get,    "Indicate reference-point").
variable(fixed_alignment, bool := @off, both,   "<-alignment is specified").

:- free(@dia_proto_recogniser).
:- pce_global(@dia_proto_recogniser, make_dia_proto_recogniser).

make_dia_proto_recogniser(R) :-
    new(DI, @event?receiver),
    new(Dev, DI?device),
    new(IsTarget, message(Dev, instance_of, dia_target_dialog)),
    new(CanResize, @event?receiver?can_resize == @on),

    new(R, handler_group(
            new(RG, resize_gesture(left)),
            new(_DG, drag_and_drop_gesture(left, '', @off)),
            new(_,  click_gesture(left, '', single,
                                  message(DI, help_ui))),
            new(EG, click_gesture(left, '', double,
                                  message(DI, edit_attributes))))),
    send(RG, condition, and(CanResize, IsTarget)),
    send(EG, condition, IsTarget).


event(DI, Ev:event) :->
    "Process event"::
    (   get(DI?device, mode, run)
    ->  send(DI, send_super, event, Ev)
    ;   send(@dia_proto_recogniser, event, Ev)
    ).


help_ui(DI) :->
    "Provide simple help"::
    send(DI?frame, report, status,  % Lourens van der Meij.  Thanks
         'Use double-left-click to edit; left-drag to move or copy').


behaviour_model(DI, Model:object) :<-
    "Related behaviour model"::
    get(DI, hypered, behaviour_model, Model).


edit_attributes(DI) :->
    "Start attribute editor"::
    get(DI?window, attribute_editor, Ed),
    get(DI?window, mode, Mode),
    get(DI, proto, Proto),
    findall(Att, attribute(Mode, Proto, Att), Atts),
    (   Atts == []
    ->  send(DI, report, warning, 'No attributes in "%s" mode', Mode)
    ;   maplist(att_to_pce, Atts, PceAtts),
        VectorTerm =.. [vector|PceAtts],
        send(Ed, send_vector, client, DI, VectorTerm),
        send(Ed, open),
        send(Ed, expose)
    ).

att_to_pce(Atom, Atom) :-
    atom(Atom),
    !.
att_to_pce(Term, tuple(Att, Cond)) :-
    Term =.. [Att, Cond].


reference_x(DI, X:'0..100') :->
    "X-coordinate of <->reference"::
    get(DI?area, width, W),
    RX is (W*X)//100,
    (   get(DI, reference, Ref)
    ->  send(Ref, x, RX),
        send(DI, send_class, reference, Ref) % avoid addressing attribute
    ;   send(DI, reference, point(RX, 0))
    ).
reference_x(DI, X:'0..100') :<-
    "X-coordinate of <->reference"::
    (   get(DI?reference, x, RX)
    ->  get(DI?area, width, W),
        X is (100*RX) // W
    ;   X = 0
    ).
reference_y(DI, Y:'0..100') :->
    "Y-coordinate of <->reference"::
    get(DI?area, height, H),
    RY is (H*Y)//100,
    (   get(DI, reference, Ref)
    ->  send(Ref, y, RY),
        send(DI, send_class, reference, Ref) % avoid addressing attribute
    ;   send(DI, reference, point(0, RY))
    ).
reference_y(DI, Y:'0..100') :<-
    "Y-coordinate of <->reference"::
    (   get(DI?reference, y, RY)
    ->  get(DI?area, height, H),
        Y is (100*RY) // H
    ;   Y = 0
    ).


fixed_reference(DI, Val:bool) :->
    "Floating or fixed reference position"::
    (   Val == @on
    ->  (   get(DI, reference, Ref)
        ->  send(DI, reference, Ref)
        ;   send(DI, reference, point(0,0))
        )
    ;   send(DI, reference, @default)
    ).
fixed_reference(DI, Val:bool) :<-
    "Is reference fixed"::
    get(DI, slot, reference, Ref),
    (   Ref == @default
    ->  Val = @off
    ;   Val = @on
    ).


geometry(DI, X:[int], Y:[int], W:[int], H:[int]) :->
    "Handle ref-indicator"::
    send(DI, send_super, geometry, X, Y, W, H),
    update_indicator_position(DI).


update_indicator_position(DI, Ind) :-
    get(DI, displayed, @on),
    get(DI, reference, point(RX, RY)),
    !,
    send(Ind, displayed, @on),
    send(Ind, center, point(DI?x + RX, DI?y + RY)).
update_indicator_position(_DI, Ind) :-
    send(Ind, displayed, @off).

update_indicator_position(DI) :-
    get(DI, ref_indicator, Ind),
    (   Ind \== @nil
    ->  update_indicator_position(DI, Ind)
    ;   true
    ).

displayed(DI, Val:bool) :->
    "Handle ref-indicator"::
    send(DI, send_super, displayed, Val),
    update_indicator_position(DI).


device(DI, Dev:device*) :->
    "Handle ref-indicator"::
    send(DI, send_super, device, Dev),
    (   get(DI, ref_indicator, Ind), Ind \== @nil
    ->  (   Dev == @nil
        ->  send(Ind, device, @nil)
        ;   send(Ind, device, Dev?overlay),
            update_indicator_position(DI)
        )
    ;   true
    ).


reference(DI, Ref:[point]) :->
    "Handle ref-indicator"::
    send(DI, send_super, reference, Ref),
    update_indicator_position(DI).


ref_indicator(DI, Ind:graphical*) :->
    "Change reference indication"::
    (   get(DI, ref_indicator, Old),
        Old \== @nil
    ->  send(Old, device, @nil)
    ;   true
    ),
    send(DI, slot, ref_indicator, Ind),
    (   Ind \== @nil
    ->  send(Ind, device, DI?device?overlay),
        update_indicator_position(DI, Ind)
    ;   true
    ).

                 /*******************************
                 *    ASSOCIATED POPUP MENU     *
                 *******************************/

popup_items(B, Items:chain) :->
    (   send(Items, empty)
    ->  send(B, popup, @nil)
    ;   (   get(B, popup, P), P \== @nil
        ->  true
        ;   send(B, popup, new(P, popup))
        ),
        send(P, clear),
        send(Items, for_all, message(P, append, @arg1))
    ).
popup_items(B, Items:chain) :<-
    (   get(B, popup, P), P \== @nil
    ->  get(P, members, Items)
    ;   new(Items, chain)
    ).

clear_popup(B) :->
    (   get(B, popup, P), P \== @nil
    ->  send(P, clear)
    ;   true
    ).

has_popup(B, V:bool) :->
    (   V == @off
    ->  send(B, popup, @nil)
    ;   (   get(B, popup, P), P \== @nil
        ->  true
        ;   send(B, popup, new(popup))
        )
    ).
has_popup(B, V:bool) :<-
    (   get(B, popup, P), P \== @nil
    ->  V = @on
    ;   V = @off
    ).

:- pce_end_class.


:- pce_begin_class(dia_proto_menu, menu).
:- use_class_template(dia_proto).

members(M, Items:chain) :->
    send(M, clear),
    send(Items, for_all, message(M, append, @arg1)).

:- pce_end_class.

:- pce_begin_class(dia_proto_menu_item, menu_item,
                   "Editable menu-item").
:- use_class_template(dia_proto).

variable(proto,         name := menu_item,      get, "Prototype").

name(MI, Name:name) :<-
    get(MI, print_name, Str),
    get(Str, value, Name).

behaviour_model(DI, Model:object) :<-
    "Related behaviour model"::
    get(DI, hypered, behaviour_model, Model).

:- pce_end_class.

:- pce_begin_class(dia_proto_text_item, text_item).
:- use_class_template(dia_proto).

dia_argument_type(TI, Selector:name, Type:type) :<-
    "The type of the <-selection is <-type"::
    (   Selector == selection
    ->  get(TI, type, Type)
    ;   get(TI, get_super, dia_argument_type, Type)
    ).

:- pce_end_class.

:- pce_begin_class(dia_proto_list_browser, list_browser,
                   "Editable list_browser").
:- use_class_template(dia_proto).

name(LB, Name:name) :->
    "Update ->label too"::
    send(LB, send_super, name, Name),
    (   get(LB, show_label, @on)
    ->  get(Name, label_name, LabelName),
        send(LB, label, LabelName)
    ;   true
    ).


dia_argument_type(LB, Selector:name, Type:type) :<-
    "The type of the <-selection"::
    (   Selector == selection
    ->  (   get(LB, multiple_selection, @on)
        ->  get(@pce, convert, chain, type, Type)
        ;   get(@pce, convert, 'dict_item*', type, Type)
        )
    ;   get(LB, get_super, dia_argument_type, Type)
    ).

:- pce_end_class.

:- pce_begin_class(dia_proto_label, label, "Editable label").
:- use_class_template(dia_proto).
:- pce_end_class.

:- pce_begin_class(dia_proto_slider, slider, "Editable slider").
:- use_class_template(dia_proto).
:- pce_end_class.

:- pce_begin_class(dia_proto_button, button, "Editable button").
:- use_class_template(dia_proto).
:- pce_end_class.

:- pce_begin_class(dia_proto_editor, editor, "Editable editor").
:- use_class_template(dia_proto).
:- pce_end_class.



%       make_proto_class(+Class, -ProtoClassName)
%
%       Create a prototype class by inserting the dia_proto template.  As
%       (of xpce-5.x.y), use_class_template/2 can only be used as a directive,
%       this must be done using a temporary file.

make_proto_class(ClassSpec, ProtoClassName) :-
    get(@pce, convert, ClassSpec, class, Class),
    get(Class, name, ClassName),
    get(dia_proto_, append, ClassName, ProtoClassName),
    (   get(@pce, convert, ProtoClassName, class, _)
    ->  true
    ;   new(F, file),
        get(F, name, TmpFile),
        open(TmpFile, write, Fd),
        format(Fd, ':- module(''~w'', []).~n~n', [ProtoClassName]),
        format(Fd, ':- use_module(library(pce)).~n', []),
        format(Fd, ':- use_module(library(pce_template)).~n~n', []),
        format(Fd, ':- pce_begin_class(~w, ~w, "Dialog prototype").~n',
               [ProtoClassName, ClassName]),
        format(Fd, ':- use_class_template(dia_proto).~n', []),
        format(Fd, ':- pce_end_class.~n', []),
        close(Fd),
        use_module(TmpFile),
        send(F, remove)
    ).


                 /*******************************
                 *            TARGET            *
                 *******************************/

:- pce_begin_class(dia_dialog, dialog, "Editable dialog").

variable(mode, {create,layout,action,run} := create, get, "Current mode").
variable(overlay, device, get, "Overlay for feedback stuff").

initialise(D, Label:[name], Size:[size]) :->
    send(D, send_super, initialise, Label, Size),
    send(D, display, new(Overlay, device)),
    send(D, slot, overlay, Overlay),
    send(Overlay, auto_align, @off).

:- pce_end_class.


:- pce_begin_class(dia_target_dialog, dia_dialog, "Target dialog").

class_variable(size, size, size(400, 200)).

initialise(D, Label:[name], Size:[size]) :->
    default(Size, class_variable(D, size), Sz),
    send(D, send_super, initialise, Label),
    send(D, size, Sz).              % force explicit size


unlink(D) :->
    "Remove from editor"::
    (   get(D, editor, Editor)
    ->  send(Editor, deleted_target, D)
    ;   true
    ),
    send(D, send_super, unlink).


report_to(D, Obj:visual) :<-
    "Delegate errors to the editor"::
    (   get(D, mode, run)
    ->  get(D, get_super, report_to, Obj)
    ;   get(D, editor, Obj)
    ).


editor(D, Editor:frame) :<-
    "The dialog editor"::
    get(D, hypered, editor, Editor).


drop(D, DI:graphical, Pos:point) :->
    (   get(DI, device, D)          % move
    ->  send(DI, position, Pos)
    ;   send(DI, instance_of, msg_object)
    ->  get(DI, ui_object, UI),
        send(D, drop, UI, Pos)
    ;   get(DI, clone, Clone),      % import
        send(Clone, lock_object, @on),
        (   get(DI, device, @nil)   % source has no device
        ->  get(Clone, proto, Proto),
            proto(Proto, _, _, Actions),
            forall(member(Action, Actions),
                   (   Action = (Selector := Arg)
                   ->  send(Clone, Selector, Arg)
                   ;   send(Clone, Action)
                   )),
            get(Clone?area, width, W0),
            (   send(Clone, has_send_method, label_width)
            ->  ignore(send(Clone, label_width, @default))
            ;   true
            ),
            get(Clone?area, width, W1),
            send(Pos, x, Pos?x + W0-W1)
        ;   true                    % copy from other dialog
        ),
        send(D, display, Clone, Pos),
        send(Clone, lock_object, @off),
        send(D?overlay, expose),
        (   get(D, mode, layout)
        ->  send(Clone, ref_indicator, bitmap(@mark_handle_image))
        ;   true
        )
    ).


preview_drop(D, DI:graphical*, Pos:[point]) :->
    (   DI == @nil                  % stop the preview
    ->  (   get(D, attribute, preview_outline, OL)
        ->  send(OL, device, @nil),
            send(D, delete_attribute, preview_outline)
        ;   true
        )
    ;   get(D, attribute, preview_outline, OL) % moving outline
    ->  send(OL, position, Pos)
    ;   (   send(DI, instance_of, msg_object)
        ->  get(DI, ui_object, UI)
        ;   \+ send(DI, instance_of, msg_port),
            UI = DI
        ),
        get(UI?area, size, size(W, H)), % move or import
        send(D, attribute, preview_outline, new(OL, box(W, H))),
        send(OL, texture, dotted),
        send(D, display, OL, Pos)
    ).



:- pce_global(@dia_dialog_recogniser, make_dia_dialog_recogniser).
:- free(@dia_dialog_recogniser).

make_dia_dialog_recogniser(G) :-
    D = @receiver,
    new(NoRunMode, @arg1?receiver?(mode) \== run), % @arg1 is the event
    new(G, handler_group(new(C, click_gesture(left, '', single,
                                              message(D, make_current))),
                         new(A, click_gesture(left, '', double,
                                              message(D,
                                                      edit_attributes))))),
    send(C, condition, NoRunMode),
    send(A, condition, NoRunMode).


event(D, Ev:event) :->
    (   send(D, send_super, event, Ev)
    ->  true
    ;   send(@dia_dialog_recogniser, event, Ev)
    ).


make_current(D) :->
    "Make this dialog editor the current one"::
    get(D, editor, Editor),
    send(Editor, target, D),
    send(Editor, mode, D?(mode)).


edit_attributes(D) :->
    "Edit window attributes"::
    get(D, proto, Proto),
    get(D, mode, Mode),
    get(D, attribute_editor, Ed),
    findall(Att, attribute(Mode, Proto, Att), Atts),
    (   Atts == []
    ->  send(D, report, warning,
             'No attributes in "%s" mode', Mode)
    ;   maplist(att_to_pce, Atts, PceAtts),
        VectorTerm =.. [vector|PceAtts],
        send(Ed, send_vector, client, D, VectorTerm),
        send(Ed, open)
    ).


proto(_D, Proto:name) :<-
    "Prototype-name (for attribute editor)"::
    Proto = dialog.


gap_x(D, G:'0..') :->
    send(D?gap, width, G).
gap_y(D, G:'0..') :->
    send(D?gap, height, G).
gap_x(D, G:'0..') :<-
    get(D?gap, width, G).
gap_y(D, G:'0..') :<-
    get(D?gap, height, G).


name(D, Name:name) :->
    get(D, name, OldName),
    send(D, send_super, name, Name),
    (   get(D, hypered, editor, Editor)
    ->  get(Editor, member, browser, Browser),
        get(Browser, member, OldName, DI),
        send(DI, key, Name)
    ;   true
    ),
    get(Name, label_name, Label),
    send(D, frame_label, Label).

frame_label(D, Label:name) :->
    send(D?frame, label, Label).
frame_label(D, Label:name) :<-
    get(D?frame, label, Label).


mode(D, Mode:{create,layout,action,run}) :->
    "Switch current mode"::
    (   get(D, mode, Mode)
    ->  true
    ;   send(D, slot, mode, Mode),
        (   Mode == run
        ->  send(D, keyboard_focus, @nil),
            send(D, advance)
        ;   true
        ),
        fix_layout_mode(D, Mode)
    ).

fix_layout_mode(D, Mode) :-
    (   Mode == layout
    ->  Mark = create(bitmap, @mark_handle_image)
    ;   Mark = @nil
    ),
    get(D, overlay, Ovl),
    send(D?graphicals, for_all,
         if(@arg1 \== Ovl, message(@arg1, ref_indicator, Mark))).


attribute_editor(D, Ed:dia_attribute_editor) :->
    new(_, dia_transient_hyper(D, Ed, attribute_editor, target_dialog)).

attribute_editor(D, Ed:dia_attribute_editor) :<-
    "Lookup existing or create editor"::
    (   get(D, hypered, attribute_editor, Ed)
    ->  true
    ;   new(Ed, dia_attribute_editor('Attribute Editor')),
        send(Ed, confirm_done, @off),
        send(D, attribute_editor, Ed)
    ).

                 /*******************************
                 *         LAYOUT STUFF         *
                 *******************************/

fix_layout(D) :->
    "Fix the layout"::
    send(D, save_dialog_layout),
    layout_dialog(D).


save_dialog_layout(D) :->
    "Save layout for later ->undo"::
    get(D, overlay, Overlay),
    send(D?graphicals, for_all,
         if(@arg1 \== Overlay,
            message(@arg1, attribute,
                    undo_position, @arg1?area?position))).

restore_dialog_layout(D) :->
    "Restore saved dialog layout"::
    new(UndoPos, ?(@arg1, attribute, undo_position)),
    (   get(D?graphicals, find, UndoPos, _)
    ->  get(D, overlay, Overlay),
        send(D?graphicals, for_all,
             if(@arg1 \== Overlay,
                and(message(@arg1, above, @nil),
                    message(@arg1, below, @nil),
                    message(@arg1, left,  @nil),
                    message(@arg1, right, @nil),
                    if(message(@arg1, has_send_method, label_width),
                       if(message(@arg1, label_width, @default))),
                    if(message(@arg1, position,
                               ?(@arg1, attribute, undo_position))))))
    ;   send(D, report, warning, 'No undo information')
    ).


fit_size(D) :->
    "Recompute layout and update size"::
    get(D, bounding_box, area(_, _, W, H)),
    get(D, gap, size(GW, GH)),
    NW is W+2*GW,
    NH is H+2*GH,
    send(D, size, size(NW, NH)).


                 /*******************************
                 *     SOURCE CODE GENERATION   *
                 *******************************/

pretty_print(Term, String) :-
    new(F, file),
    get(F, name, TmpNam),
    telling(Old), tell(TmpNam),
    pretty_print(Term),
    told, tell(Old),
    send(F, open, read),
    get(F, read, String),
    send(F, remove),
    send(F, free).


prolog_source(D, String:string) :<-
    "Prolog source-code for dialog"::
    source(D, Source),
    pretty_print(Source, String).


behaviour_model(D, Model:msg_model) :<-
    "Related behaviour model"::
    get(D, hypered, behaviour_model, Model).


open_behaviour_model(D) :->
    "Open the behaviour-model view"::
    (   get(D, behaviour_model, Model)
    ->  send(Model, open),
        send(Model?frame, expose)
    ;   new(Model, msg_model_editor(D)),
        send(Model, open)
    ).


catch_all(D, Selector:name, Args:any ...) :->
    "Catch run-mode messages"::
    (   get(D, mode, run)
    ->  send(@pce, send_vector, write_ln, 'Message', Selector, Args)
    ;   fail                        % editor error: report
    ).


:- pce_end_class.


                 /*******************************
                 *            SOURCE            *
                 *******************************/

:- pce_begin_class(dia_proto_icon, bitmap, "Icon for a prototype").

variable(prototype,     graphical,      get, "Represented prototype").

initialise(I, Proto:graphical) :->
    get(Proto, proto, Name),
    icon(Name, Image),
    send(I, send_super, initialise, Image),
    send(I, slot, prototype, Proto).

:- pce_global(@dia_proto_icon_recogniser,
              make_dia_proto_icon_recogniser).

make_dia_proto_icon_recogniser(G) :-
    new(I, handler(area_enter,
                   message(@receiver, report, status,
                           @receiver?identify))),
    new(O, handler(area_exit,
                   message(@receiver, report, status, ''))),
    new(D, drag_and_drop_gesture(left, @default, @off)),
    send(D, get_source, @arg1?prototype),
    new(H, click_gesture(left, '', single,
                         message(@event?receiver, report, status,
                                 'Use left button to drag object to dialog'))),
    new(G, handler_group(I, O, D, H)).

event(I, Ev:event) :->
    (   send(I, send_super, event, Ev)
    ;   send(@dia_proto_icon_recogniser, event, Ev)
    ).

identify(I, Str:string) :<-
    "Print identification string"::
    get(I?prototype, proto, Name),
    summary(Name, Text),
    Str = string(Text).

:- pce_end_class.


:- pce_begin_class(dia_source_dialog, dia_dialog, "Prototype dialog").

drop(D, DI:graphical, _Pos) :->
    (   (   get(DI, device, D)
        ;   get(DI, device, @nil)
        )
    ->  true
    ;   send(DI, free)              % delete
    ).


preview_drop(D, DI:graphical*) :->
    send(@event, instance_of, event),
    get(@event, window, Window),
    (   DI == @nil
    ->  (   get(D, attribute, saved_drag_cursor, Cursor)
        ->  send(Window, focus_cursor, Cursor),
            send(D, delete_attribute, saved_drag_cursor)
        ;   true
        )
    ;   (   (   get(DI, device, D)
            ;       get(DI, device, @nil)
            )
        ->  fail
        ;   send(D, attribute, saved_drag_cursor, Window?focus_cursor),
            send(Window, focus_cursor, pirate)
        )
    ).


fill(D) :->
    "Append all prototypes"::
    forall(proto(Name, _, _, _),
           send(D, append_prototype, Name)).

append_prototype(D, Name:name) :->
    "Append named prototype"::
    proto(Name, Term, Options, _Realise),
    Term =.. [Class|Args],
    make_proto_class(Class, ProtoClass),
    NewTerm =.. [ProtoClass|Args],
    new(Item, NewTerm),
    forall(member(Selector := Value, Options),
           send(Item, Selector, Value)),
    send(Item, proto, Name),
    send(D, append, dia_proto_icon(Item)).

append(D, I:dia_proto_icon) :->
    "Append in 4 rows"::
    (   (   \+ get(D?graphicals, find,
                   message(@arg1, instance_of, dia_proto_icon), _)
        ;   items_in_current_row(D, 9)
        )
    ->  send(D, send_super, append, I)
    ;   send(D, send_super, append, I, right)
    ).

items_in_current_row(D, N) :-
    get(D?graphicals, tail, Last),
    count_items(Last, N).

count_items(I, N) :-
    get(I, left, I2), I2 \== @nil,
    !,
    count_items(I2, N2),
    N is N2 + 1.
count_items(_I, 1).

:- pce_end_class.


                 /*******************************
                 *           TOPLEVEL           *
                 *******************************/

:- pce_begin_class(dia_editor, frame, "Dialog Editor").

initialise(DE) :->
    initialise_paths,
    dia_version(Version),
    send(DE, send_super, initialise,
         string('Dialog Editor --- Version %s', Version)),
    send(DE, icon_label, 'Dialog Editor'),
    send(DE, append, new(TD, dialog)),
    send(new(B, browser), left, new(MD, dialog)),
    send(B, label, 'Dialog windows'),
    send(B, open_message,
         and(message(DE?target, show, @on),
             message(DE?target, expose))),
    send(B?list_browser, recogniser,
         new(G, drag_and_drop_dict_item_gesture)),
    send(G, get_source, ?(DE, target, @arg1?key)),
    send(B, height, 5),
    send(B, below, TD),
    send(new(BD, dialog), below, B),
    send(BD, name, info_dialog),
    send(BD, gap, size(10,0)),
    send(BD, append, label(reporter, 'See file menu for help')),
    send(new(SD, dia_source_dialog), below, BD),
    fill_top_dialog(TD),
    fill_menu_dialog(MD),
    send(SD, fill),
    send(DE, mode, create).


report_to(DE, Reporter:graphical) :<-
    get(DE, member, top_dialog, Dialog),
    get(Dialog, member, reporter, Reporter).


fill_top_dialog(D) :-
    send(D, name, top_dialog),
    send(D, gap, size(5,5)),
    get(D, frame, Frame),
    new(Target, Frame?target),

    send(D, append, new(MB, menu_bar)),
    send(MB, append, new(File, popup(file))),
    send(MB, append, new(Open, popup(open_dialog))),

    send_list(File, append,
              [ menu_item(help,
                          message(@helper, give_help, dialog,
                                  'main:file')),
                menu_item(bluffers_guide,
                          message(@helper, give_help, dialog,
                                  bluffers_guide),
                          end_group := @on),
                menu_item(new_dialog, message(Frame, create_target),
                          end_group := @on),
                menu_item(reload_from_id, message(Frame, reload),
                          end_group := @on),
                menu_item(load, message(Frame, load)),
                menu_item(save, message(Frame, save),
                          condition := ?(Target,attribute,dia_save_file)),
                menu_item(save_as, message(Frame, save_as),
                          condition := Target),
                menu_item(save_all, message(Frame, save_all),
                          end_group := @on),
                menu_item(postscript_as, message(Frame, postscript_as),
                          condition := Target,
                          end_group := @on),
                menu_item(quit, message(Frame, destroy))
              ]),

    NoTargets = not(message(Frame?targets, empty)),

    send_list(Open, append,
              [ menu_item(open,
                          message(Target, show, @on),
                          condition := Target),
                menu_item(open_all,
                          message(Frame, open_all_targets),
                          end_group := @on,
                          condition := NoTargets),
                menu_item(close,
                          message(Target, show, @off),
                          condition := Target),
                menu_item(close_all,
                          message(Frame, close_all_targets),
                          end_group := @on,
                          condition := NoTargets)
              ]).


fill_menu_dialog(D) :-
    send(D, name, mode_dialog),
    get(D, frame, Frame),
    send(D, append, label(title, 'Mode', bold)),
    send(D, append,
         new(M, menu(mode, choice, message(Frame, mode, @arg1)))),
    send(M, append, create),
    send(M, append, layout),
    send(M, append, action),
    send(M, append, run),
    send(M, show_label, @off),
    send(M, compute),
    send(M, reference, point(M?item_offset?x, 0)),
    send(D, append, new(Dev, device)),
    send(Dev, name, button_device),
    send(Dev, alignment, column).


mode(DE, Mode:{create,layout,action,run}) :->
    get(DE, member, mode_dialog, Dialog),
    get(Dialog, member, mode, Menu),
    get(Dialog, member, button_device, Dev),
    send(Menu, selection, Mode),
    send(Dev, clear),
    (   mode_button(Mode, _, _)
    ->  forall(mode_button(Mode, Label, Message),
               send(Dev, append_dialog_item,
                    button(Label, Message)))
    ;   send(Dev, display, graphical(0, 0, 1, button(x)?height))
    ),
    send(Dev, layout_dialog),
    send(Dialog, layout),
    (   get(DE, target, Target)
    ->  send(Target, mode, Mode)
    ;   true
    ).

:- pce_global(@dia_target, new(@receiver?frame?target)).

mode_button(layout, layout,      message(@dia_target, fix_layout)).
mode_button(layout, undo,        message(@dia_target, restore_dialog_layout)).
mode_button(layout, fit,         message(@dia_target, fit_size)).
mode_button(action, behaviour_model,
                                 message(@dia_target, open_behaviour_model)).
mode_button(run,    reset,       message(@dia_target, reset)).


create_target(DE) :->
    send(DE, mode, create),
    get(DE, member, browser, B),
    between(1, 10000, N),
    get(string('dialog_%s', N), value, DefName),
    \+ get(B, member, DefName, _),
    !,
    prompter('Create new dialog',
             [ name:name  = Name/DefName
             ]),
    new(Target, new(dia_target_dialog)),
    send(Target, name, Name),
    get(DE, area, Area),
    get(Area, top_side, Top),
    get(Area, right_side, Right),
    send(Target, open, point(Right+20, Top-30)),
    send(DE, target, Target).

target(DE, D:dia_target_dialog) :->
    get(D, name, Name),
    get(DE, member, browser, B),
    (   get(B, member, Name, DI)
    ->  true
    ;   send(B, append, new(DI, dict_item(Name)))
    ),
    send(B, selection, DI),
    (   get(DE, target, Name, _)
    ->  true
    ;   new(_, dia_transient_hyper(DE, D, target, editor))
    ).

deleted_target(DE, D:dia_target_dialog) :->
    "Update browser after target has been deleted"::
    (   send(DE, unlinking)
    ->  true
    ;   get(DE, member, browser, B),
        get(D, name, Name),
        send(B, delete, Name)
    ).


target(DE, Name:[name], D:dia_target_dialog) :<-
    (   Name == @default
    ->  get(DE, member, browser, B),
        (   get(B, selection, DI), DI \== @nil
        ->  get(DI, key, TheName)
        ;   fail                    % warning?
        )
    ;   TheName = Name
    ),
    get(DE, hypered, target, @arg3?name == TheName, D).


targets(DE, Targets:chain) :<-
    "New chain holding the current targets"::
    get(DE, member, browser, B),
    new(Targets, chain),
    send(B?members, for_all,
         message(Targets, append, ?(DE, target, @arg1?key))).


close_all_targets(DE) :->
    "->show: @off all <-targets"::
    send(DE?targets, for_all, message(@arg1, show, @off)).

open_all_targets(DE) :->
    "->show: @on all <-targets"::
    send(DE?targets, for_all, message(@arg1, show, @on)).


save_as(DE) :->
    get(DE, target, Target),
    get(Target, name, N0),
    get(N0, ensure_suffix, '.dia', N1),
    get(@finder, file, @off, '.dia', @default, N1, File),
    send(Target, attribute, attribute(dia_save_file, File)),
    send(DE, save).


save(DE) :->
    get(DE, target, Target),
    (   get(Target, attribute, dia_save_file, File)
    ->  send(file(File), backup),
        (   get(Target, find_hyper, behaviour_model, Hyper)
        ->  send(Hyper, save_in_file, File)
        ;   send(Target, save_in_file, File)
        ),
        send(DE, report, status, 'Saved in %s', file(File)?base_name)
    ;   send(DE, save_as)           % ask file first
    ).


save_all(DE, File:[file]) :->
    "Save group of dialogs, so they stay together"::
    (   File == @default
    ->  get(@finder, file, @off, '.dia', @default, TheFileName),
        new(TheFile, file(TheFileName))
    ;   TheFile = File
    ),
    get(DE, member, browser, B),
    new(Ch, chain),
    send(B?dict?members, for_all,
         message(DE, add_target, Ch, @arg1?key)),
    send(Ch, save_in_file, TheFile),
    send(Ch, done),
    send(DE, report, status, 'Saved in %s', TheFile?base_name).


add_target(DE, Ch:chain, TargetName:name) :->
    "Add target to chain (part of ->save_all"::
    get(DE, target, TargetName, Target),
    (   get(Target, find_hyper, behaviour_model, Hyper)
    ->  send(Ch, append, Hyper)
    ;   send(Ch, append, Target)
    ).


load(DE) :->
    get(@finder, file, @on, '.dia', File),
    get(file(File), object, Loaded),
    rebind(DE, Loaded, File).


rebind(DE, Loaded, File) :-
    (   send(Loaded, instance_of, chain)
    ->  (   send(Loaded, empty)
        ->  send(DE, report, error, 'No dialog windows in %N', File)
        ;   send(Loaded, for_all,
                 message(@prolog, rebind, DE, @arg1, @default))
        )
    ;   (   send(Loaded, instance_of, hyper)
        ->  get(Loaded, from, Target),
            send(Loaded?to, relink)
        ;   send(Loaded, instance_of, dia_target_dialog)
        ->  Target = Loaded
        ),
        (   File \== @default
        ->  send(Target, dia_save_file, File)
        ;   true
        ),
        send(DE, target, Target),
        send(DE, mode, Target?(mode))
    ).


current_dialog(Key, Module) :-
    current_predicate(dialog, Module:dialog(_,_)),
    Module:dialog(Key, _).


reload(DE) :->
    "Import from source"::
    new(D, dialog('Import dialog from key')),
    send(D, append, new(B, list_browser(@default, 30))),
    forall(current_dialog(Key, _Module),
           (functor(Key, Id, _Arity),
            send(B, append, Id))),
    send(B, open_message, message(D, return, @arg1?key)),
    send(D, append, button(load, message(D, return, B?selection?key))),
    send(D, append, button(cancel, message(D, return, @nil))),
    get(D, confirm_centered, DE?area?center, Key),
    send(D, destroy),
    load_dialog(Target, Key),
    send(Target, name, Key),
    get(DE, area, Area),
    get(Area, top_side, Top),
    get(Area, right_side, Right),
    send(Target, open, point(Right+20, Top-30)),
    send(DE, target, Target).


postscript_as(DE) :->
    "Dump <-target as PostScript"::
    get(DE, target, Target),
    (   get(Target, attribute, dia_postscript_file, PsFile)
    ->  true
    ;   get(Target, attribute, dia_save_file, SaveFile)
    ->  get(SaveFile, delete_suffix, '.dia', Base),
        get(Base, ensure_suffix, '.ps', PsFile)
    ;   get(Target, name, Base),
        get(Base, ensure_suffix, '.ps', PsFile)
    ),
    get(@finder, file, @off, '.ps', @default, PsFile, ThePsFile),
    postscript(Target?frame, ThePsFile).

:- pce_end_class.
