1 files changed, 1775 insertions, 0 deletions

diff --git a/apps/plugins/puzzles/src/osx.m b/apps/plugins/puzzles/src/osx.m
new file mode 100644
index 0000000000..9d74da1574
--- /dev/null
+++ b/apps/plugins/puzzles/src/osx.m
@@ -0,0 +1,1775 @@
+/*
+ * Mac OS X / Cocoa front end to puzzles.
+ *
+ * Still to do:
+ * 
+ *  - I'd like to be able to call up context help for a specific
+ *    game at a time.
+ * 
+ * Mac interface issues that possibly could be done better:
+ * 
+ *  - is there a better approach to frontend_default_colour?
+ *
+ *  - do we need any more options in the Window menu?
+ *
+ *  - can / should we be doing anything with the titles of the
+ *    configuration boxes?
+ * 
+ *  - not sure what I should be doing about default window
+ *    placement. Centring new windows is a bit feeble, but what's
+ *    better? Is there a standard way to tell the OS "here's the
+ *    _size_ of window I want, now use your best judgment about the
+ *    initial position"?
+ *     + there's a standard _policy_ on window placement, given in
+ *       the HI guidelines. Have to implement it ourselves though,
+ *       bah.
+ *
+ *  - a brief frob of the Mac numeric keypad suggests that it
+ *    generates numbers no matter what you do. I wonder if I should
+ *    try to figure out a way of detecting keypad codes so I can
+ *    implement UP_LEFT and friends. Alternatively, perhaps I
+ *    should simply assign the number keys to UP_LEFT et al?
+ *    They're not in use for anything else right now.
+ *
+ *  - see if we can do anything to one-button-ise the multi-button
+ *    dependent puzzle UIs:
+ *     - Pattern is a _little_ unwieldy but not too bad (since
+ *       generally you never need the middle button unless you've
+ *       made a mistake, so it's just click versus command-click).
+ *     - Net is utterly vile; having normal click be one rotate and
+ *       command-click be the other introduces a horrid asymmetry,
+ *       and yet requiring a shift key for _each_ click would be
+ *       even worse because rotation feels as if it ought to be the
+ *       default action. I fear this is why the Flash Net had the
+ *       UI it did...
+ *        + I've tried out an alternative dragging interface for
+ *          Net; it might work nicely for stylus-based platforms
+ *          where you have better hand/eye feedback for the thing
+ *          you're clicking on, but it's rather unwieldy on the
+ *          Mac. I fear even shift-clicking is better than that.
+ *
+ *  - Should we _return_ to a game configuration sheet once an
+ *    error is reported by midend_set_config, to allow the user to
+ *    correct the one faulty input and keep the other five OK ones?
+ *    The Apple `one sheet at a time' restriction would require me
+ *    to do this by closing the config sheet, opening the alert
+ *    sheet, and then reopening the config sheet when the alert is
+ *    closed; and the human interface types, who presumably
+ *    invented the one-sheet-at-a-time rule for good reasons, might
+ *    look with disfavour on me trying to get round them to fake a
+ *    nested sheet. On the other hand I think there are good
+ *    practical reasons for wanting it that way. Uncertain.
+ * 
+ *  - User feedback dislikes nothing happening when you start the
+ *    app; they suggest a finder-like window containing an icon for
+ *    each puzzle type, enabling you to start one easily. Needs
+ *    thought.
+ * 
+ * Grotty implementation details that could probably be improved:
+ * 
+ *  - I am _utterly_ unconvinced that NSImageView was the right way
+ *    to go about having a window with a reliable backing store! It
+ *    just doesn't feel right; NSImageView is a _control_. Is there
+ *    a simpler way?
+ * 
+ *  - Resizing is currently very bad; rather than bother to work
+ *    out how to resize the NSImageView, I just splatter and
+ *    recreate it.
+ */
+
+#define COMBINED /* we put all the puzzles in one binary in this port */
+
+#include <ctype.h>
+#include <time.h>
+#include <sys/time.h>
+#import <Cocoa/Cocoa.h>
+#include "puzzles.h"
+
+/* ----------------------------------------------------------------------
+ * Global variables.
+ */
+
+/*
+ * The `Type' menu. We frob this dynamically to allow the user to
+ * choose a preset set of settings from the current game.
+ */
+NSMenu *typemenu;
+
+/*
+ * Forward reference.
+ */
+extern const struct drawing_api osx_drawing;
+
+/*
+ * The NSApplication shared instance, which I'll want to refer to from
+ * a few places here and there.
+ */
+NSApplication *app;
+
+/* ----------------------------------------------------------------------
+ * Miscellaneous support routines that aren't part of any object or
+ * clearly defined subsystem.
+ */
+
+void fatal(char *fmt, ...)
+{
+    va_list ap;
+    char errorbuf[2048];
+    NSAlert *alert;
+
+    va_start(ap, fmt);
+    vsnprintf(errorbuf, lenof(errorbuf), fmt, ap);
+    va_end(ap);
+
+    alert = [NSAlert alloc];
+    /*
+     * We may have come here because we ran out of memory, in which
+     * case it's entirely likely that that alloc will fail, so we
+     * should have a fallback of some sort.
+     */
+    if (!alert) {
+        fprintf(stderr, "fatal error (and NSAlert failed): %s\n", errorbuf);
+    } else {
+        alert = [[alert init] autorelease];
+        [alert addButtonWithTitle:@"Oh dear"];
+        [alert setInformativeText:[NSString stringWithUTF8String:errorbuf]];
+        [alert runModal];
+    }
+    exit(1);
+}
+
+void frontend_default_colour(frontend *fe, float *output)
+{
+    /* FIXME: Is there a system default we can tap into for this? */
+    output[0] = output[1] = output[2] = 0.8F;
+}
+
+void get_random_seed(void **randseed, int *randseedsize)
+{
+    time_t *tp = snew(time_t);
+    time(tp);
+    *randseed = (void *)tp;
+    *randseedsize = sizeof(time_t);
+}
+
+static void savefile_write(void *wctx, void *buf, int len)
+{
+    FILE *fp = (FILE *)wctx;
+    fwrite(buf, 1, len, fp);
+}
+
+static int savefile_read(void *wctx, void *buf, int len)
+{
+    FILE *fp = (FILE *)wctx;
+    int ret;
+
+    ret = fread(buf, 1, len, fp);
+    return (ret == len);
+}
+
+/*
+ * Since this front end does not support printing (yet), we need
+ * this stub to satisfy the reference in midend_print_puzzle().
+ */
+void document_add_puzzle(document *doc, const game *game, game_params *par,
+                         game_state *st, game_state *st2)
+{
+}
+
+/*
+ * setAppleMenu isn't listed in the NSApplication header, but an
+ * NSApp responds to it, so we're adding it here to silence
+ * warnings. (This was removed from the headers in 10.4, so we
+ * only need to include it for 10.4+.)
+ */
+#if MAC_OS_X_VERSION_MAX_ALLOWED >= 1040
+@interface NSApplication(NSAppleMenu)
+- (void)setAppleMenu:(NSMenu *)menu;
+@end
+#endif
+
+/* ----------------------------------------------------------------------
+ * Tiny extension to NSMenuItem which carries a payload of a `void
+ * *', allowing several menu items to invoke the same message but
+ * pass different data through it.
+ */
+@interface DataMenuItem : NSMenuItem
+{
+    void *payload;
+}
+- (void)setPayload:(void *)d;
+- (void *)getPayload;
+@end
+@implementation DataMenuItem
+- (void)setPayload:(void *)d
+{
+    payload = d;
+}
+- (void *)getPayload
+{
+    return payload;
+}
+@end
+
+/* ----------------------------------------------------------------------
+ * Utility routines for constructing OS X menus.
+ */
+
+NSMenu *newmenu(const char *title)
+{
+    return [[[NSMenu allocWithZone:[NSMenu menuZone]]
+             initWithTitle:[NSString stringWithUTF8String:title]]
+            autorelease];
+}
+
+NSMenu *newsubmenu(NSMenu *parent, const char *title)
+{
+    NSMenuItem *item;
+    NSMenu *child;
+
+    item = [[[NSMenuItem allocWithZone:[NSMenu menuZone]]
+             initWithTitle:[NSString stringWithUTF8String:title]
+             action:NULL
+             keyEquivalent:@""]
+            autorelease];
+    child = newmenu(title);
+    [item setEnabled:YES];
+    [item setSubmenu:child];
+    [parent addItem:item];
+    return child;
+}
+
+id initnewitem(NSMenuItem *item, NSMenu *parent, const char *title,
+               const char *key, id target, SEL action)
+{
+    unsigned mask = NSCommandKeyMask;
+
+    if (key[strcspn(key, "-")]) {
+        while (*key && *key != '-') {
+            int c = tolower((unsigned char)*key);
+            if (c == 's') {
+                mask |= NSShiftKeyMask;
+            } else if (c == 'o' || c == 'a') {
+                mask |= NSAlternateKeyMask;
+            }
+            key++;
+        }
+        if (*key)
+            key++;
+    }
+
+    item = [[item initWithTitle:[NSString stringWithUTF8String:title]
+             action:NULL
+             keyEquivalent:[NSString stringWithUTF8String:key]]
+            autorelease];
+
+    if (*key)
+        [item setKeyEquivalentModifierMask: mask];
+
+    [item setEnabled:YES];
+    [item setTarget:target];
+    [item setAction:action];
+
+    [parent addItem:item];
+
+    return item;
+}
+
+NSMenuItem *newitem(NSMenu *parent, char *title, char *key,
+                    id target, SEL action)
+{
+    return initnewitem([NSMenuItem allocWithZone:[NSMenu menuZone]],
+                       parent, title, key, target, action);
+}
+
+/* ----------------------------------------------------------------------
+ * About box.
+ */
+
+@class AboutBox;
+
+@interface AboutBox : NSWindow
+{
+}
+- (id)init;
+@end
+
+@implementation AboutBox
+- (id)init
+{
+    NSRect totalrect;
+    NSView *views[16];
+    int nviews = 0;
+    NSImageView *iv;
+    NSTextField *tf;
+    NSFont *font1 = [NSFont systemFontOfSize:0];
+    NSFont *font2 = [NSFont boldSystemFontOfSize:[font1 pointSize] * 1.1];
+    const int border = 24;
+    int i;
+    double y;
+
+    /*
+     * Construct the controls that go in the About box.
+     */
+
+    iv = [[NSImageView alloc] initWithFrame:NSMakeRect(0,0,64,64)];
+    [iv setImage:[NSImage imageNamed:@"NSApplicationIcon"]];
+    views[nviews++] = iv;
+
+    tf = [[NSTextField alloc]
+          initWithFrame:NSMakeRect(0,0,400,1)];
+    [tf setEditable:NO];
+    [tf setSelectable:NO];
+    [tf setBordered:NO];
+    [tf setDrawsBackground:NO];
+    [tf setFont:font2];
+    [tf setStringValue:@"Simon Tatham's Portable Puzzle Collection"];
+    [tf sizeToFit];
+    views[nviews++] = tf;
+
+    tf = [[NSTextField alloc]
+          initWithFrame:NSMakeRect(0,0,400,1)];
+    [tf setEditable:NO];
+    [tf setSelectable:NO];
+    [tf setBordered:NO];
+    [tf setDrawsBackground:NO];
+    [tf setFont:font1];
+    [tf setStringValue:[NSString stringWithUTF8String:ver]];
+    [tf sizeToFit];
+    views[nviews++] = tf;
+
+    /*
+     * Lay the controls out.
+     */
+    totalrect = NSMakeRect(0,0,0,0);
+    for (i = 0; i < nviews; i++) {
+        NSRect r = [views[i] frame];
+        if (totalrect.size.width < r.size.width)
+            totalrect.size.width = r.size.width;
+        totalrect.size.height += border + r.size.height;
+    }
+    totalrect.size.width += 2 * border;
+    totalrect.size.height += border;
+    y = totalrect.size.height;
+    for (i = 0; i < nviews; i++) {
+        NSRect r = [views[i] frame];
+        r.origin.x = (totalrect.size.width - r.size.width) / 2;
+        y -= border + r.size.height;
+        r.origin.y = y;
+        [views[i] setFrame:r];
+    }
+
+    self = [super initWithContentRect:totalrect
+            styleMask:(NSTitledWindowMask | NSMiniaturizableWindowMask |
+                       NSClosableWindowMask)
+            backing:NSBackingStoreBuffered
+            defer:YES];
+
+    for (i = 0; i < nviews; i++)
+        [[self contentView] addSubview:views[i]];
+
+    [self center];                     /* :-) */
+
+    return self;
+}
+@end
+
+/* ----------------------------------------------------------------------
+ * The front end presented to midend.c.
+ * 
+ * This is mostly a subclass of NSWindow. The actual `frontend'
+ * structure passed to the midend contains a variety of pointers,
+ * including that window object but also including the image we
+ * draw on, an ImageView to display it in the window, and so on.
+ */
+
+@class GameWindow;
+@class MyImageView;
+
+struct frontend {
+    GameWindow *window;
+    NSImage *image;
+    MyImageView *view;
+    NSColor **colours;
+    int ncolours;
+    int clipped;
+    int w, h;
+};
+
+@interface MyImageView : NSImageView
+{
+    GameWindow *ourwin;
+}
+- (void)setWindow:(GameWindow *)win;
+- (void)mouseEvent:(NSEvent *)ev button:(int)b;
+- (void)mouseDown:(NSEvent *)ev;
+- (void)mouseDragged:(NSEvent *)ev;
+- (void)mouseUp:(NSEvent *)ev;
+- (void)rightMouseDown:(NSEvent *)ev;
+- (void)rightMouseDragged:(NSEvent *)ev;
+- (void)rightMouseUp:(NSEvent *)ev;
+- (void)otherMouseDown:(NSEvent *)ev;
+- (void)otherMouseDragged:(NSEvent *)ev;
+- (void)otherMouseUp:(NSEvent *)ev;
+@end
+
+@interface GameWindow : NSWindow
+{
+    const game *ourgame;
+    midend *me;
+    struct frontend fe;
+    struct timeval last_time;
+    NSTimer *timer;
+    NSWindow *sheet;
+    config_item *cfg;
+    int cfg_which;
+    NSView **cfg_controls;
+    int cfg_ncontrols;
+    NSTextField *status;
+    struct preset_menu *preset_menu;
+    NSMenuItem **preset_menu_items;
+    int n_preset_menu_items;
+}
+- (id)initWithGame:(const game *)g;
+- (void)dealloc;
+- (void)processButton:(int)b x:(int)x y:(int)y;
+- (void)processKey:(int)b;
+- (void)keyDown:(NSEvent *)ev;
+- (void)activateTimer;
+- (void)deactivateTimer;
+- (void)setStatusLine:(char *)text;
+- (void)resizeForNewGameParams;
+- (void)updateTypeMenuTick;
+@end
+
+@implementation MyImageView
+
+- (void)setWindow:(GameWindow *)win
+{
+    ourwin = win;
+}
+
+- (void)mouseEvent:(NSEvent *)ev button:(int)b
+{
+    NSPoint point = [self convertPoint:[ev locationInWindow] fromView:nil];
+    [ourwin processButton:b x:point.x y:point.y];
+}
+
+- (void)mouseDown:(NSEvent *)ev
+{
+    unsigned mod = [ev modifierFlags];
+    [self mouseEvent:ev button:((mod & NSCommandKeyMask) ? RIGHT_BUTTON :
+                                (mod & NSShiftKeyMask) ? MIDDLE_BUTTON :
+                                LEFT_BUTTON)];
+}
+- (void)mouseDragged:(NSEvent *)ev
+{
+    unsigned mod = [ev modifierFlags];
+    [self mouseEvent:ev button:((mod & NSCommandKeyMask) ? RIGHT_DRAG :
+                                (mod & NSShiftKeyMask) ? MIDDLE_DRAG :
+                                LEFT_DRAG)];
+}
+- (void)mouseUp:(NSEvent *)ev
+{
+    unsigned mod = [ev modifierFlags];
+    [self mouseEvent:ev button:((mod & NSCommandKeyMask) ? RIGHT_RELEASE :
+                                (mod & NSShiftKeyMask) ? MIDDLE_RELEASE :
+                                LEFT_RELEASE)];
+}
+- (void)rightMouseDown:(NSEvent *)ev
+{
+    unsigned mod = [ev modifierFlags];
+    [self mouseEvent:ev button:((mod & NSShiftKeyMask) ? MIDDLE_BUTTON :
+                                RIGHT_BUTTON)];
+}
+- (void)rightMouseDragged:(NSEvent *)ev
+{
+    unsigned mod = [ev modifierFlags];
+    [self mouseEvent:ev button:((mod & NSShiftKeyMask) ? MIDDLE_DRAG :
+                                RIGHT_DRAG)];
+}
+- (void)rightMouseUp:(NSEvent *)ev
+{
+    unsigned mod = [ev modifierFlags];
+    [self mouseEvent:ev button:((mod & NSShiftKeyMask) ? MIDDLE_RELEASE :
+                                RIGHT_RELEASE)];
+}
+- (void)otherMouseDown:(NSEvent *)ev
+{
+    [self mouseEvent:ev button:MIDDLE_BUTTON];
+}
+- (void)otherMouseDragged:(NSEvent *)ev
+{
+    [self mouseEvent:ev button:MIDDLE_DRAG];
+}
+- (void)otherMouseUp:(NSEvent *)ev
+{
+    [self mouseEvent:ev button:MIDDLE_RELEASE];
+}
+@end
+
+@implementation GameWindow
+- (void)setupContentView
+{
+    NSRect frame;
+    int w, h;
+
+    if (status) {
+        frame = [status frame];
+        frame.origin.y = frame.size.height;
+    } else
+        frame.origin.y = 0;
+    frame.origin.x = 0;
+
+    w = h = INT_MAX;
+    midend_size(me, &w, &h, FALSE);
+    frame.size.width = w;
+    frame.size.height = h;
+    fe.w = w;
+    fe.h = h;
+
+    fe.image = [[NSImage alloc] initWithSize:frame.size];
+    fe.view = [[MyImageView alloc] initWithFrame:frame];
+    [fe.view setImage:fe.image];
+    [fe.view setWindow:self];
+
+    midend_redraw(me);
+
+    [[self contentView] addSubview:fe.view];
+}
+- (id)initWithGame:(const game *)g
+{
+    NSRect rect = { {0,0}, {0,0} }, rect2;
+    int w, h;
+
+    ourgame = g;
+    preset_menu = NULL;
+    preset_menu_items = NULL;
+
+    fe.window = self;
+
+    me = midend_new(&fe, ourgame, &osx_drawing, &fe);
+    /*
+     * If we ever need to open a fresh window using a provided game
+     * ID, I think the right thing is to move most of this method
+     * into a new initWithGame:gameID: method, and have
+     * initWithGame: simply call that one and pass it NULL.
+     */
+    midend_new_game(me);
+    w = h = INT_MAX;
+    midend_size(me, &w, &h, FALSE);
+    rect.size.width = w;
+    rect.size.height = h;
+    fe.w = w;
+    fe.h = h;
+
+    /*
+     * Create the status bar, which will just be an NSTextField.
+     */
+    if (midend_wants_statusbar(me)) {
+        status = [[NSTextField alloc] initWithFrame:NSMakeRect(0,0,100,50)];
+        [status setEditable:NO];
+        [status setSelectable:NO];
+        [status setBordered:YES];
+        [status setBezeled:YES];
+        [status setBezelStyle:NSTextFieldSquareBezel];
+        [status setDrawsBackground:YES];
+        [[status cell] setTitle:@DEFAULT_STATUSBAR_TEXT];
+        [status sizeToFit];
+        rect2 = [status frame];
+        rect.size.height += rect2.size.height;
+        rect2.size.width = rect.size.width;
+        rect2.origin.x = rect2.origin.y = 0;
+        [status setFrame:rect2];
+    } else
+        status = nil;
+
+    self = [super initWithContentRect:rect
+            styleMask:(NSTitledWindowMask | NSMiniaturizableWindowMask |
+                       NSClosableWindowMask)
+            backing:NSBackingStoreBuffered
+            defer:YES];
+    [self setTitle:[NSString stringWithUTF8String:ourgame->name]];
+
+    {
+        float *colours;
+        int i, ncolours;
+
+        colours = midend_colours(me, &ncolours);
+        fe.ncolours = ncolours;
+        fe.colours = snewn(ncolours, NSColor *);
+
+        for (i = 0; i < ncolours; i++) {
+            fe.colours[i] = [[NSColor colorWithDeviceRed:colours[i*3]
+                              green:colours[i*3+1] blue:colours[i*3+2]
+                              alpha:1.0] retain];
+        }
+    }
+
+    [self setupContentView];
+    if (status)
+        [[self contentView] addSubview:status];
+    [self setIgnoresMouseEvents:NO];
+
+    [self center];                     /* :-) */
+
+    return self;
+}
+
+- (void)dealloc
+{
+    int i;
+    for (i = 0; i < fe.ncolours; i++) {
+        [fe.colours[i] release];
+    }
+    sfree(fe.colours);
+    sfree(preset_menu_items);
+    midend_free(me);
+    [super dealloc];
+}
+
+- (void)processButton:(int)b x:(int)x y:(int)y
+{
+    if (!midend_process_key(me, x, fe.h - 1 - y, b))
+        [self close];
+}
+
+- (void)processKey:(int)b
+{
+    if (!midend_process_key(me, -1, -1, b))
+        [self close];
+}
+
+- (void)keyDown:(NSEvent *)ev
+{
+    NSString *s = [ev characters];
+    int i, n = [s length];
+
+    for (i = 0; i < n; i++) {
+        int c = [s characterAtIndex:i];
+
+        /*
+         * ASCII gets passed straight to midend_process_key.
+         * Anything above that has to be translated to our own
+         * function key codes.
+         */
+        if (c >= 0x80) {
+            int mods = FALSE;
+            switch (c) {
+              case NSUpArrowFunctionKey:
+                c = CURSOR_UP;
+                mods = TRUE;
+                break;
+              case NSDownArrowFunctionKey:
+                c = CURSOR_DOWN;
+                mods = TRUE;
+                break;
+              case NSLeftArrowFunctionKey:
+                c = CURSOR_LEFT;
+                mods = TRUE;
+                break;
+              case NSRightArrowFunctionKey:
+                c = CURSOR_RIGHT;
+                mods = TRUE;
+                break;
+              default:
+                continue;
+            }
+
+            if (mods) {
+                if ([ev modifierFlags] & NSShiftKeyMask)
+                    c |= MOD_SHFT;
+                if ([ev modifierFlags] & NSControlKeyMask)
+                    c |= MOD_CTRL;
+            }
+        }
+
+        if (c >= '0' && c <= '9' && ([ev modifierFlags] & NSNumericPadKeyMask))
+            c |= MOD_NUM_KEYPAD;
+
+        [self processKey:c];
+    }
+}
+
+- (void)activateTimer
+{
+    if (timer != nil)
+        return;
+
+    timer = [NSTimer scheduledTimerWithTimeInterval:0.02
+             target:self selector:@selector(timerTick:)
+             userInfo:nil repeats:YES];
+    gettimeofday(&last_time, NULL);
+}
+
+- (void)deactivateTimer
+{
+    if (timer == nil)
+        return;
+
+    [timer invalidate];
+    timer = nil;
+}
+
+- (void)timerTick:(id)sender
+{
+    struct timeval now;
+    float elapsed;
+    gettimeofday(&now, NULL);
+    elapsed = ((now.tv_usec - last_time.tv_usec) * 0.000001F +
+               (now.tv_sec - last_time.tv_sec));
+    midend_timer(me, elapsed);
+    last_time = now;
+}
+
+- (void)showError:(char *)message
+{
+    NSAlert *alert;
+
+    alert = [[[NSAlert alloc] init] autorelease];
+    [alert addButtonWithTitle:@"Bah"];
+    [alert setInformativeText:[NSString stringWithUTF8String:message]];
+    [alert beginSheetModalForWindow:self modalDelegate:nil
+     didEndSelector:NULL contextInfo:nil];
+}
+
+- (void)newGame:(id)sender
+{
+    [self processKey:'n'];
+}
+- (void)restartGame:(id)sender
+{
+    midend_restart_game(me);
+}
+- (void)saveGame:(id)sender
+{
+    NSSavePanel *sp = [NSSavePanel savePanel];
+
+    if ([sp runModal] == NSFileHandlingPanelOKButton) {
+       const char *name = [[sp filename] UTF8String];
+
+        FILE *fp = fopen(name, "w");
+
+        if (!fp) {
+            [self showError:"Unable to open save file"];
+            return;
+        }
+
+        midend_serialise(me, savefile_write, fp);
+
+        fclose(fp);
+    }
+}
+- (void)loadSavedGame:(id)sender
+{
+    NSOpenPanel *op = [NSOpenPanel openPanel];
+
+    [op setAllowsMultipleSelection:NO];
+
+    if ([op runModalForTypes:nil] == NSOKButton) {
+        /*
+         * This used to be
+         *
+         *    [[[op filenames] objectAtIndex:0] cString]
+         *
+         * but the plain cString method became deprecated and Xcode 7
+         * started complaining about it. Since OS X 10.9 we can
+         * apparently use the more modern API
+         *
+         *    [[[op URLs] objectAtIndex:0] fileSystemRepresentation]
+         *
+         * but the alternative below still compiles with Xcode 7 and
+         * is a bit more backwards compatible, so I'll try it for the
+         * moment.
+         */
+        const char *name = [[[op filenames] objectAtIndex:0]
+                               cStringUsingEncoding:
+                                   [NSString defaultCStringEncoding]];
+        char *err;
+
+        FILE *fp = fopen(name, "r");
+
+        if (!fp) {
+            [self showError:"Unable to open saved game file"];
+            return;
+        }
+
+        err = midend_deserialise(me, savefile_read, fp);
+
+        fclose(fp);
+
+        if (err) {
+            [self showError:err];
+            return;
+        }
+
+        [self resizeForNewGameParams];
+        [self updateTypeMenuTick];
+    }
+}
+- (void)undoMove:(id)sender
+{
+    [self processKey:'u'];
+}
+- (void)redoMove:(id)sender
+{
+    [self processKey:'r'&0x1F];
+}
+
+- (void)copy:(id)sender
+{
+    char *text;
+
+    if ((text = midend_text_format(me)) != NULL) {
+        NSPasteboard *pb = [NSPasteboard generalPasteboard];
+        NSArray *a = [NSArray arrayWithObject:NSStringPboardType];
+        [pb declareTypes:a owner:nil];
+        [pb setString:[NSString stringWithUTF8String:text]
+         forType:NSStringPboardType];
+    } else
+        NSBeep();
+}
+
+- (void)solveGame:(id)sender
+{
+    char *msg;
+
+    msg = midend_solve(me);
+
+    if (msg)
+        [self showError:msg];
+}
+
+- (BOOL)validateMenuItem:(NSMenuItem *)item
+{
+    if ([item action] == @selector(copy:))
+        return (ourgame->can_format_as_text_ever &&
+                midend_can_format_as_text_now(me) ? YES : NO);
+    else if ([item action] == @selector(solveGame:))
+        return (ourgame->can_solve ? YES : NO);
+    else
+        return [super validateMenuItem:item];
+}
+
+- (void)clearTypeMenu
+{
+    int i;
+
+    while ([typemenu numberOfItems] > 1)
+        [typemenu removeItemAtIndex:0];
+    [[typemenu itemAtIndex:0] setState:NSOffState];
+
+    for (i = 0; i < n_preset_menu_items; i++)
+        preset_menu_items[i] = NULL;
+}
+
+- (void)updateTypeMenuTick
+{
+    int i, n;
+
+    n = midend_which_preset(me);
+
+    for (i = 0; i < n_preset_menu_items; i++)
+        if (preset_menu_items[i])
+            [preset_menu_items[i] setState:(i == n ? NSOnState : NSOffState)];
+
+    /*
+     * The Custom menu item is always right at the bottom of the
+     * Type menu.
+     */
+    [[typemenu itemAtIndex:[typemenu numberOfItems]-1]
+             setState:(n < 0 ? NSOnState : NSOffState)];
+}
+
+- (void)populateTypeMenu:(NSMenu *)nsmenu from:(struct preset_menu *)menu
+{
+    int i;
+
+    /*
+     * We process the entries in reverse order so that (in the
+     * top-level Type menu at least) we don't disturb the 'Custom'
+     * item which remains fixed even when we change back and forth
+     * between puzzle type windows.
+     */
+    for (i = menu->n_entries; i-- > 0 ;) {
+        struct preset_menu_entry *entry = &menu->entries[i];
+        NSMenuItem *item;
+
+        if (entry->params) {
+            DataMenuItem *ditem;
+            ditem = [[[DataMenuItem alloc]
+                        initWithTitle:[NSString stringWithUTF8String:
+                                                    entry->title]
+                               action:NULL keyEquivalent:@""]
+                       autorelease];
+
+            [ditem setTarget:self];
+            [ditem setAction:@selector(presetGame:)];
+            [ditem setPayload:entry->params];
+
+            preset_menu_items[entry->id] = ditem;
+
+            item = ditem;
+        } else {
+            NSMenu *nssubmenu;
+
+            item = [[[NSMenuItem alloc]
+                        initWithTitle:[NSString stringWithUTF8String:
+                                                    entry->title]
+                               action:NULL keyEquivalent:@""]
+                       autorelease];
+            nssubmenu = newmenu(entry->title);
+            [item setSubmenu:nssubmenu];
+
+            [self populateTypeMenu:nssubmenu from:entry->submenu];
+        }
+
+        [item setEnabled:YES];
+        [nsmenu insertItem:item atIndex:0];
+    }
+}
+
+- (void)becomeKeyWindow
+{
+    [self clearTypeMenu];
+
+    [super becomeKeyWindow];
+
+    if (!preset_menu) {
+        int i;
+        preset_menu = midend_get_presets(me, &n_preset_menu_items);
+        preset_menu_items = snewn(n_preset_menu_items, NSMenuItem *);
+        for (i = 0; i < n_preset_menu_items; i++)
+            preset_menu_items[i] = NULL;
+    }
+
+    if (preset_menu->n_entries > 0) {
+        [typemenu insertItem:[NSMenuItem separatorItem] atIndex:0];
+        [self populateTypeMenu:typemenu from:preset_menu];
+    }
+
+    [self updateTypeMenuTick];
+}
+
+- (void)resignKeyWindow
+{
+    [self clearTypeMenu];
+    [super resignKeyWindow];
+}
+
+- (void)close
+{
+    [self clearTypeMenu];
+    [super close];
+}
+
+- (void)resizeForNewGameParams
+{
+    NSSize size = {0,0};
+    int w, h;
+
+    w = h = INT_MAX;
+    midend_size(me, &w, &h, FALSE);
+    size.width = w;
+    size.height = h;
+    fe.w = w;
+    fe.h = h;
+
+    if (status) {
+        NSRect frame = [status frame];
+        size.height += frame.size.height;
+        frame.size.width = size.width;
+        [status setFrame:frame];
+    }
+
+#ifndef GNUSTEP
+    NSDisableScreenUpdates();
+#endif
+    [self setContentSize:size];
+    [self setupContentView];
+#ifndef GNUSTEP
+    NSEnableScreenUpdates();
+#endif
+}
+
+- (void)presetGame:(id)sender
+{
+    game_params *params = [sender getPayload];
+
+    midend_set_params(me, params);
+    midend_new_game(me);
+
+    [self resizeForNewGameParams];
+    [self updateTypeMenuTick];
+}
+
+- (void)startConfigureSheet:(int)which
+{
+    NSButton *ok, *cancel;
+    int actw, acth, leftw, rightw, totalw, h, thish, y;
+    int k;
+    NSRect rect, tmprect;
+    const int SPACING = 16;
+    char *title;
+    config_item *i;
+    int cfg_controlsize;
+    NSTextField *tf;
+    NSButton *b;
+    NSPopUpButton *pb;
+
+    assert(sheet == NULL);
+
+    /*
+     * Every control we create here is going to have this size
+     * until we tell it to calculate a better one.
+     */
+    tmprect = NSMakeRect(0, 0, 100, 50);
+
+    /*
+     * Set up OK and Cancel buttons. (Actually, MacOS doesn't seem
+     * to be fond of generic OK and Cancel wording, so I'm going to
+     * rename them to something nicer.)
+     */
+    actw = acth = 0;
+
+    cancel = [[NSButton alloc] initWithFrame:tmprect];
+    [cancel setBezelStyle:NSRoundedBezelStyle];
+    [cancel setTitle:@"Abandon"];
+    [cancel setTarget:self];
+    [cancel setKeyEquivalent:@"\033"];
+    [cancel setAction:@selector(sheetCancelButton:)];
+    [cancel sizeToFit];
+    rect = [cancel frame];
+    if (actw < rect.size.width) actw = rect.size.width;
+    if (acth < rect.size.height) acth = rect.size.height;
+
+    ok = [[NSButton alloc] initWithFrame:tmprect];
+    [ok setBezelStyle:NSRoundedBezelStyle];
+    [ok setTitle:@"Accept"];
+    [ok setTarget:self];
+    [ok setKeyEquivalent:@"\r"];
+    [ok setAction:@selector(sheetOKButton:)];
+    [ok sizeToFit];
+    rect = [ok frame];
+    if (actw < rect.size.width) actw = rect.size.width;
+    if (acth < rect.size.height) acth = rect.size.height;
+
+    totalw = SPACING + 2 * actw;
+    h = 2 * SPACING + acth;
+
+    /*
+     * Now fetch the midend config data and go through it creating
+     * controls.
+     */
+    cfg = midend_get_config(me, which, &title);
+    sfree(title);                      /* FIXME: should we use this somehow? */
+    cfg_which = which;
+
+    cfg_ncontrols = cfg_controlsize = 0;
+    cfg_controls = NULL;
+    leftw = rightw = 0;
+    for (i = cfg; i->type != C_END; i++) {
+        if (cfg_controlsize < cfg_ncontrols + 5) {
+            cfg_controlsize = cfg_ncontrols + 32;
+            cfg_controls = sresize(cfg_controls, cfg_controlsize, NSView *);
+        }
+
+        thish = 0;
+
+        switch (i->type) {
+          case C_STRING:
+            /*
+             * Two NSTextFields, one being a label and the other
+             * being an edit box.
+             */
+
+            tf = [[NSTextField alloc] initWithFrame:tmprect];
+            [tf setEditable:NO];
+            [tf setSelectable:NO];
+            [tf setBordered:NO];
+            [tf setDrawsBackground:NO];
+            [[tf cell] setTitle:[NSString stringWithUTF8String:i->name]];
+            [tf sizeToFit];
+            rect = [tf frame];
+            if (thish < rect.size.height + 1) thish = rect.size.height + 1;
+            if (leftw < rect.size.width + 1) leftw = rect.size.width + 1;
+            cfg_controls[cfg_ncontrols++] = tf;
+
+            tf = [[NSTextField alloc] initWithFrame:tmprect];
+            [tf setEditable:YES];
+            [tf setSelectable:YES];
+            [tf setBordered:YES];
+            [[tf cell] setTitle:[NSString stringWithUTF8String:i->sval]];
+            [tf sizeToFit];
+            rect = [tf frame];
+            /*
+             * We impose a minimum and maximum width on editable
+             * NSTextFields. If we allow them to size themselves to
+             * the contents of the text within them, then they will
+             * look very silly if that text is only one or two
+             * characters, and equally silly if it's an absolutely
+             * enormous Rectangles or Pattern game ID!
+             */
+            if (rect.size.width < 75) rect.size.width = 75;
+            if (rect.size.width > 400) rect.size.width = 400;
+
+            if (thish < rect.size.height + 1) thish = rect.size.height + 1;
+            if (rightw < rect.size.width + 1) rightw = rect.size.width + 1;
+            cfg_controls[cfg_ncontrols++] = tf;
+            break;
+
+          case C_BOOLEAN:
+            /*
+             * A checkbox is an NSButton with a type of
+             * NSSwitchButton.
+             */
+            b = [[NSButton alloc] initWithFrame:tmprect];
+            [b setBezelStyle:NSRoundedBezelStyle];
+            [b setButtonType:NSSwitchButton];
+            [b setTitle:[NSString stringWithUTF8String:i->name]];
+            [b sizeToFit];
+            [b setState:(i->ival ? NSOnState : NSOffState)];
+            rect = [b frame];
+            if (totalw < rect.size.width + 1) totalw = rect.size.width + 1;
+            if (thish < rect.size.height + 1) thish = rect.size.height + 1;
+            cfg_controls[cfg_ncontrols++] = b;
+            break;
+
+          case C_CHOICES:
+            /*
+             * A pop-up menu control is an NSPopUpButton, which
+             * takes an embedded NSMenu. We also need an
+             * NSTextField to act as a label.
+             */
+
+            tf = [[NSTextField alloc] initWithFrame:tmprect];
+            [tf setEditable:NO];
+            [tf setSelectable:NO];
+            [tf setBordered:NO];
+            [tf setDrawsBackground:NO];
+            [[tf cell] setTitle:[NSString stringWithUTF8String:i->name]];
+            [tf sizeToFit];
+            rect = [tf frame];
+            if (thish < rect.size.height + 1) thish = rect.size.height + 1;
+            if (leftw < rect.size.width + 1) leftw = rect.size.width + 1;
+            cfg_controls[cfg_ncontrols++] = tf;
+
+            pb = [[NSPopUpButton alloc] initWithFrame:tmprect pullsDown:NO];
+            [pb setBezelStyle:NSRoundedBezelStyle];
+            {
+                char c, *p;
+
+                p = i->sval;
+                c = *p++;
+                while (*p) {
+                    char *q, *copy;
+
+                    q = p;
+                    while (*p && *p != c) p++;
+
+                    copy = snewn((p-q) + 1, char);
+                    memcpy(copy, q, p-q);
+                    copy[p-q] = '\0';
+                    [pb addItemWithTitle:[NSString stringWithUTF8String:copy]];
+                    sfree(copy);
+
+                    if (*p) p++;
+                }
+            }
+            [pb selectItemAtIndex:i->ival];
+            [pb sizeToFit];
+
+            rect = [pb frame];
+            if (rightw < rect.size.width + 1) rightw = rect.size.width + 1;
+            if (thish < rect.size.height + 1) thish = rect.size.height + 1;
+            cfg_controls[cfg_ncontrols++] = pb;
+            break;
+        }
+
+        h += SPACING + thish;
+    }
+
+    if (totalw < leftw + SPACING + rightw)
+        totalw = leftw + SPACING + rightw;
+    if (totalw > leftw + SPACING + rightw) {
+        int excess = totalw - (leftw + SPACING + rightw);
+        int leftexcess = leftw * excess / (leftw + rightw);
+        int rightexcess = excess - leftexcess;
+        leftw += leftexcess;
+        rightw += rightexcess;
+    }
+
+    /*
+     * Now go through the list again, setting the final position
+     * for each control.
+     */
+    k = 0;
+    y = h;
+    for (i = cfg; i->type != C_END; i++) {
+        y -= SPACING;
+        thish = 0;
+        switch (i->type) {
+          case C_STRING:
+          case C_CHOICES:
+            /*
+             * These two are treated identically, since both expect
+             * a control on the left and another on the right.
+             */
+            rect = [cfg_controls[k] frame];
+            if (thish < rect.size.height + 1)
+                thish = rect.size.height + 1;
+            rect = [cfg_controls[k+1] frame];
+            if (thish < rect.size.height + 1)
+                thish = rect.size.height + 1;
+            rect = [cfg_controls[k] frame];
+            rect.origin.y = y - thish/2 - rect.size.height/2;
+            rect.origin.x = SPACING;
+            rect.size.width = leftw;
+            [cfg_controls[k] setFrame:rect];
+            rect = [cfg_controls[k+1] frame];
+            rect.origin.y = y - thish/2 - rect.size.height/2;
+            rect.origin.x = 2 * SPACING + leftw;
+            rect.size.width = rightw;
+            [cfg_controls[k+1] setFrame:rect];
+            k += 2;
+            break;
+
+          case C_BOOLEAN:
+            rect = [cfg_controls[k] frame];
+            if (thish < rect.size.height + 1)
+                thish = rect.size.height + 1;
+            rect.origin.y = y - thish/2 - rect.size.height/2;
+            rect.origin.x = SPACING;
+            rect.size.width = totalw;
+            [cfg_controls[k] setFrame:rect];
+            k++;
+            break;
+        }
+        y -= thish;
+    }
+
+    assert(k == cfg_ncontrols);
+
+    [cancel setFrame:NSMakeRect(SPACING+totalw/4-actw/2, SPACING, actw, acth)];
+    [ok setFrame:NSMakeRect(SPACING+3*totalw/4-actw/2, SPACING, actw, acth)];
+
+    sheet = [[NSWindow alloc]
+             initWithContentRect:NSMakeRect(0,0,totalw + 2*SPACING,h)
+             styleMask:NSTitledWindowMask | NSClosableWindowMask
+             backing:NSBackingStoreBuffered
+             defer:YES];
+
+    [[sheet contentView] addSubview:cancel];
+    [[sheet contentView] addSubview:ok];
+
+    for (k = 0; k < cfg_ncontrols; k++)
+        [[sheet contentView] addSubview:cfg_controls[k]];
+
+    [app beginSheet:sheet modalForWindow:self
+     modalDelegate:nil didEndSelector:NULL contextInfo:nil];
+}
+
+- (void)specificGame:(id)sender
+{
+    [self startConfigureSheet:CFG_DESC];
+}
+
+- (void)specificRandomGame:(id)sender
+{
+    [self startConfigureSheet:CFG_SEED];
+}
+
+- (void)customGameType:(id)sender
+{
+    [self startConfigureSheet:CFG_SETTINGS];
+}
+
+- (void)sheetEndWithStatus:(BOOL)update
+{
+    assert(sheet != NULL);
+    [app endSheet:sheet];
+    [sheet orderOut:self];
+    sheet = NULL;
+    if (update) {
+        int k;
+        config_item *i;
+        char *error;
+
+        k = 0;
+        for (i = cfg; i->type != C_END; i++) {
+            switch (i->type) {
+              case C_STRING:
+                sfree(i->sval);
+                i->sval = dupstr([[[(id)cfg_controls[k+1] cell]
+                                  title] UTF8String]);
+                k += 2;
+                break;
+              case C_BOOLEAN:
+                i->ival = [(id)cfg_controls[k] state] == NSOnState;
+                k++;
+                break;
+              case C_CHOICES:
+                i->ival = [(id)cfg_controls[k+1] indexOfSelectedItem];
+                k += 2;
+                break;
+            }
+        }
+
+        error = midend_set_config(me, cfg_which, cfg);
+        if (error) {
+            NSAlert *alert = [[[NSAlert alloc] init] autorelease];
+            [alert addButtonWithTitle:@"Bah"];
+            [alert setInformativeText:[NSString stringWithUTF8String:error]];
+            [alert beginSheetModalForWindow:self modalDelegate:nil
+             didEndSelector:NULL contextInfo:nil];
+        } else {
+            midend_new_game(me);
+            [self resizeForNewGameParams];
+            [self updateTypeMenuTick];
+        }
+    }
+    sfree(cfg_controls);
+    cfg_controls = NULL;
+}
+- (void)sheetOKButton:(id)sender
+{
+    [self sheetEndWithStatus:YES];
+}
+- (void)sheetCancelButton:(id)sender
+{
+    [self sheetEndWithStatus:NO];
+}
+
+- (void)setStatusLine:(char *)text
+{
+    [[status cell] setTitle:[NSString stringWithUTF8String:text]];
+}
+
+@end
+
+/*
+ * Drawing routines called by the midend.
+ */
+static void osx_draw_polygon(void *handle, int *coords, int npoints,
+                             int fillcolour, int outlinecolour)
+{
+    frontend *fe = (frontend *)handle;
+    NSBezierPath *path = [NSBezierPath bezierPath];
+    int i;
+
+    [[NSGraphicsContext currentContext] setShouldAntialias:YES];
+
+    for (i = 0; i < npoints; i++) {
+        NSPoint p = { coords[i*2] + 0.5, fe->h - coords[i*2+1] - 0.5 };
+        if (i == 0)
+            [path moveToPoint:p];
+        else
+            [path lineToPoint:p];
+    }
+
+    [path closePath];
+
+    if (fillcolour >= 0) {
+        assert(fillcolour >= 0 && fillcolour < fe->ncolours);
+        [fe->colours[fillcolour] set];
+        [path fill];
+    }
+
+    assert(outlinecolour >= 0 && outlinecolour < fe->ncolours);
+    [fe->colours[outlinecolour] set];
+    [path stroke];
+}
+static void osx_draw_circle(void *handle, int cx, int cy, int radius,
+                            int fillcolour, int outlinecolour)
+{
+    frontend *fe = (frontend *)handle;
+    NSBezierPath *path = [NSBezierPath bezierPath];
+
+    [[NSGraphicsContext currentContext] setShouldAntialias:YES];
+
+    [path appendBezierPathWithArcWithCenter:NSMakePoint(cx+0.5, fe->h-cy-0.5)
+        radius:radius startAngle:0.0 endAngle:360.0];
+
+    [path closePath];
+
+    if (fillcolour >= 0) {
+        assert(fillcolour >= 0 && fillcolour < fe->ncolours);
+        [fe->colours[fillcolour] set];
+        [path fill];
+    }
+
+    assert(outlinecolour >= 0 && outlinecolour < fe->ncolours);
+    [fe->colours[outlinecolour] set];
+    [path stroke];
+}
+static void osx_draw_line(void *handle, int x1, int y1, int x2, int y2, int colour)
+{
+    frontend *fe = (frontend *)handle;
+    NSBezierPath *path = [NSBezierPath bezierPath];
+    NSPoint p1 = { x1 + 0.5, fe->h - y1 - 0.5 };
+    NSPoint p2 = { x2 + 0.5, fe->h - y2 - 0.5 };
+
+    [[NSGraphicsContext currentContext] setShouldAntialias:NO];
+
+    assert(colour >= 0 && colour < fe->ncolours);
+    [fe->colours[colour] set];
+
+    [path moveToPoint:p1];
+    [path lineToPoint:p2];
+    [path stroke];
+    NSRectFill(NSMakeRect(x1, fe->h-y1-1, 1, 1));
+    NSRectFill(NSMakeRect(x2, fe->h-y2-1, 1, 1));
+}
+
+static void osx_draw_thick_line(
+    void *handle, float thickness,
+    float x1, float y1,
+    float x2, float y2,
+    int colour)
+{
+    frontend *fe = (frontend *)handle;
+    NSBezierPath *path = [NSBezierPath bezierPath];
+
+    assert(colour >= 0 && colour < fe->ncolours);
+    [fe->colours[colour] set];
+    [[NSGraphicsContext currentContext] setShouldAntialias: YES];
+    [path setLineWidth: thickness];
+    [path setLineCapStyle: NSButtLineCapStyle];
+    [path moveToPoint: NSMakePoint(x1, fe->h-y1)];
+    [path lineToPoint: NSMakePoint(x2, fe->h-y2)];
+    [path stroke];
+}
+
+static void osx_draw_rect(void *handle, int x, int y, int w, int h, int colour)
+{
+    frontend *fe = (frontend *)handle;
+    NSRect r = { {x, fe->h - y - h}, {w,h} };
+    
+    [[NSGraphicsContext currentContext] setShouldAntialias:NO];
+
+    assert(colour >= 0 && colour < fe->ncolours);
+    [fe->colours[colour] set];
+
+    NSRectFill(r);
+}
+static void osx_draw_text(void *handle, int x, int y, int fonttype,
+                          int fontsize, int align, int colour, char *text)
+{
+    frontend *fe = (frontend *)handle;
+    NSString *string = [NSString stringWithUTF8String:text];
+    NSDictionary *attr;
+    NSFont *font;
+    NSSize size;
+    NSPoint point;
+
+    [[NSGraphicsContext currentContext] setShouldAntialias:YES];
+
+    assert(colour >= 0 && colour < fe->ncolours);
+
+    if (fonttype == FONT_FIXED)
+        font = [NSFont userFixedPitchFontOfSize:fontsize];
+    else
+        font = [NSFont userFontOfSize:fontsize];
+
+    attr = [NSDictionary dictionaryWithObjectsAndKeys:
+            fe->colours[colour], NSForegroundColorAttributeName,
+            font, NSFontAttributeName, nil];
+
+    point.x = x;
+    point.y = fe->h - y;
+
+    size = [string sizeWithAttributes:attr];
+    if (align & ALIGN_HRIGHT)
+        point.x -= size.width;
+    else if (align & ALIGN_HCENTRE)
+        point.x -= size.width / 2;
+    if (align & ALIGN_VCENTRE)
+        point.y -= size.height / 2;
+
+    [string drawAtPoint:point withAttributes:attr];
+}
+static char *osx_text_fallback(void *handle, const char *const *strings,
+                               int nstrings)
+{
+    /*
+     * We assume OS X can cope with any UTF-8 likely to be emitted
+     * by a puzzle.
+     */
+    return dupstr(strings[0]);
+}
+struct blitter {
+    int w, h;
+    int x, y;
+    NSImage *img;
+};
+static blitter *osx_blitter_new(void *handle, int w, int h)
+{
+    blitter *bl = snew(blitter);
+    bl->x = bl->y = -1;
+    bl->w = w;
+    bl->h = h;
+    bl->img = [[NSImage alloc] initWithSize:NSMakeSize(w, h)];
+    return bl;
+}
+static void osx_blitter_free(void *handle, blitter *bl)
+{
+    [bl->img release];
+    sfree(bl);
+}
+static void osx_blitter_save(void *handle, blitter *bl, int x, int y)
+{
+    frontend *fe = (frontend *)handle;
+    int sx, sy, sX, sY, dx, dy, dX, dY;
+    [fe->image unlockFocus];
+    [bl->img lockFocus];
+
+    /*
+     * Find the intersection of the source and destination rectangles,
+     * so as to avoid trying to copy from outside the source image,
+     * which GNUstep dislikes.
+     *
+     * Lower-case x,y coordinates are bottom left box corners;
+     * upper-case X,Y are the top right.
+     */
+    sx = x; sy = fe->h - y - bl->h;
+    sX = sx + bl->w; sY = sy + bl->h;
+    dx = dy = 0;
+    dX = bl->w; dY = bl->h;
+    if (sx < 0) {
+        dx += -sx;
+        sx = 0;
+    }
+    if (sy < 0) {
+        dy += -sy;
+        sy = 0;
+    }
+    if (sX > fe->w) {
+        dX -= (sX - fe->w);
+        sX = fe->w;
+    }
+    if (sY > fe->h) {
+        dY -= (sY - fe->h);
+        sY = fe->h;
+    }
+
+    [fe->image drawInRect:NSMakeRect(dx, dy, dX-dx, dY-dy)
+                 fromRect:NSMakeRect(sx, sy, sX-sx, sY-sy)
+                operation:NSCompositeCopy fraction:1.0];
+    [bl->img unlockFocus];
+    [fe->image lockFocus];
+    bl->x = x;
+    bl->y = y;
+}
+static void osx_blitter_load(void *handle, blitter *bl, int x, int y)
+{
+    frontend *fe = (frontend *)handle;
+    if (x == BLITTER_FROMSAVED && y == BLITTER_FROMSAVED) {
+        x = bl->x;
+        y = bl->y;
+    }
+    [bl->img drawInRect:NSMakeRect(x, fe->h - y - bl->h, bl->w, bl->h)
+        fromRect:NSMakeRect(0, 0, bl->w, bl->h)
+        operation:NSCompositeCopy fraction:1.0];
+}
+static void osx_draw_update(void *handle, int x, int y, int w, int h)
+{
+    frontend *fe = (frontend *)handle;
+    [fe->view setNeedsDisplayInRect:NSMakeRect(x, fe->h - y - h, w, h)];
+}
+static void osx_clip(void *handle, int x, int y, int w, int h)
+{
+    frontend *fe = (frontend *)handle;
+    NSRect r = { {x, fe->h - y - h}, {w, h} };
+    
+    if (!fe->clipped)
+        [[NSGraphicsContext currentContext] saveGraphicsState];
+    [NSBezierPath clipRect:r];
+    fe->clipped = TRUE;
+}
+static void osx_unclip(void *handle)
+{
+    frontend *fe = (frontend *)handle;
+    if (fe->clipped)
+        [[NSGraphicsContext currentContext] restoreGraphicsState];
+    fe->clipped = FALSE;
+}
+static void osx_start_draw(void *handle)
+{
+    frontend *fe = (frontend *)handle;
+    [fe->image lockFocus];
+    fe->clipped = FALSE;
+}
+static void osx_end_draw(void *handle)
+{
+    frontend *fe = (frontend *)handle;
+    [fe->image unlockFocus];
+}
+static void osx_status_bar(void *handle, char *text)
+{
+    frontend *fe = (frontend *)handle;
+    [fe->window setStatusLine:text];
+}
+
+const struct drawing_api osx_drawing = {
+    osx_draw_text,
+    osx_draw_rect,
+    osx_draw_line,
+    osx_draw_polygon,
+    osx_draw_circle,
+    osx_draw_update,
+    osx_clip,
+    osx_unclip,
+    osx_start_draw,
+    osx_end_draw,
+    osx_status_bar,
+    osx_blitter_new,
+    osx_blitter_free,
+    osx_blitter_save,
+    osx_blitter_load,
+    NULL, NULL, NULL, NULL, NULL, NULL, /* {begin,end}_{doc,page,puzzle} */
+    NULL, NULL,                        /* line_width, line_dotted */
+    osx_text_fallback,
+    osx_draw_thick_line,
+};
+
+void deactivate_timer(frontend *fe)
+{
+    [fe->window deactivateTimer];
+}
+void activate_timer(frontend *fe)
+{
+    [fe->window activateTimer];
+}
+
+/* ----------------------------------------------------------------------
+ * AppController: the object which receives the messages from all
+ * menu selections that aren't standard OS X functions.
+ */
+@interface AppController : NSObject <NSApplicationDelegate>
+{
+}
+- (void)newGameWindow:(id)sender;
+- (void)about:(id)sender;
+@end
+
+@implementation AppController
+
+- (void)newGameWindow:(id)sender
+{
+    const game *g = [sender getPayload];
+    id win;
+
+    win = [[GameWindow alloc] initWithGame:g];
+    [win makeKeyAndOrderFront:self];
+}
+
+- (void)about:(id)sender
+{
+    id win;
+
+    win = [[AboutBox alloc] init];
+    [win makeKeyAndOrderFront:self];    
+}
+
+- (NSMenu *)applicationDockMenu:(NSApplication *)sender
+{
+    NSMenu *menu = newmenu("Dock Menu");
+    {
+        int i;
+
+        for (i = 0; i < gamecount; i++) {
+            id item =
+                initnewitem([DataMenuItem allocWithZone:[NSMenu menuZone]],
+                            menu, gamelist[i]->name, "", self,
+                            @selector(newGameWindow:));
+            [item setPayload:(void *)gamelist[i]];
+        }
+    }
+    return menu;
+}
+
+@end
+
+/* ----------------------------------------------------------------------
+ * Main program. Constructs the menus and runs the application.
+ */
+int main(int argc, char **argv)
+{
+    NSAutoreleasePool *pool;
+    NSMenu *menu;
+    AppController *controller;
+    NSImage *icon;
+
+    pool = [[NSAutoreleasePool alloc] init];
+
+    icon = [NSImage imageNamed:@"NSApplicationIcon"];
+    app = [NSApplication sharedApplication];
+    [app setApplicationIconImage:icon];
+
+    controller = [[[AppController alloc] init] autorelease];
+    [app setDelegate:controller];
+
+    [app setMainMenu: newmenu("Main Menu")];
+
+    menu = newsubmenu([app mainMenu], "Apple Menu");
+    newitem(menu, "About Puzzles", "", NULL, @selector(about:));
+    [menu addItem:[NSMenuItem separatorItem]];
+    [app setServicesMenu:newsubmenu(menu, "Services")];
+    [menu addItem:[NSMenuItem separatorItem]];
+    newitem(menu, "Hide Puzzles", "h", app, @selector(hide:));
+    newitem(menu, "Hide Others", "o-h", app, @selector(hideOtherApplications:));
+    newitem(menu, "Show All", "", app, @selector(unhideAllApplications:));
+    [menu addItem:[NSMenuItem separatorItem]];
+    newitem(menu, "Quit", "q", app, @selector(terminate:));
+    [app setAppleMenu: menu];
+
+    menu = newsubmenu([app mainMenu], "File");
+    newitem(menu, "Open", "o", NULL, @selector(loadSavedGame:));
+    newitem(menu, "Save As", "s", NULL, @selector(saveGame:));
+    newitem(menu, "New Game", "n", NULL, @selector(newGame:));
+    newitem(menu, "Restart Game", "r", NULL, @selector(restartGame:));
+    newitem(menu, "Specific Game", "", NULL, @selector(specificGame:));
+    newitem(menu, "Specific Random Seed", "", NULL,
+                   @selector(specificRandomGame:));
+    [menu addItem:[NSMenuItem separatorItem]];
+    {
+        NSMenu *submenu = newsubmenu(menu, "New Window");
+        int i;
+
+        for (i = 0; i < gamecount; i++) {
+            id item =
+                initnewitem([DataMenuItem allocWithZone:[NSMenu menuZone]],
+                            submenu, gamelist[i]->name, "", controller,
+                            @selector(newGameWindow:));
+            [item setPayload:(void *)gamelist[i]];
+        }
+    }
+    [menu addItem:[NSMenuItem separatorItem]];
+    newitem(menu, "Close", "w", NULL, @selector(performClose:));
+
+    menu = newsubmenu([app mainMenu], "Edit");
+    newitem(menu, "Undo", "z", NULL, @selector(undoMove:));
+    newitem(menu, "Redo", "S-z", NULL, @selector(redoMove:));
+    [menu addItem:[NSMenuItem separatorItem]];
+    newitem(menu, "Cut", "x", NULL, @selector(cut:));
+    newitem(menu, "Copy", "c", NULL, @selector(copy:));
+    newitem(menu, "Paste", "v", NULL, @selector(paste:));
+    [menu addItem:[NSMenuItem separatorItem]];
+    newitem(menu, "Solve", "S-s", NULL, @selector(solveGame:));
+
+    menu = newsubmenu([app mainMenu], "Type");
+    typemenu = menu;
+    newitem(menu, "Custom", "", NULL, @selector(customGameType:));
+
+    menu = newsubmenu([app mainMenu], "Window");
+    [app setWindowsMenu: menu];
+    newitem(menu, "Minimise Window", "m", NULL, @selector(performMiniaturize:));
+
+    menu = newsubmenu([app mainMenu], "Help");
+    newitem(menu, "Puzzles Help", "?", app, @selector(showHelp:));
+
+    [app run];
+    [pool release];
+
+    return 0;
+}