/*
 * cocoa.m
 * Copyright (C) 2019 Kovid Goyal <kovid at kovidgoyal.net>
 *
 * Distributed under terms of the GPL3 license.
 */

#define PY_SSIZE_T_CLEAN
#import <AppKit/AppKit.h>
#import <AppKit/NSWindow.h>
#import <Availability.h>
#import <IOKit/pwr_mgt/IOPMLib.h>
#include <UserNotifications/UserNotifications.h>

#include <string.h>
#include <Python.h>

static void
disable_window_tabbing(void) {
	if ([NSWindow respondsToSelector:@selector(allowsAutomaticWindowTabbing)])
        NSWindow.allowsAutomaticWindowTabbing = NO;
}

static void
remove_cocoa_menu_items(void) {
	// Remove (disable) the "Start Dictation..." and "Emoji & Symbols" menu
	// items from the "Edit" menu
	[[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"NSDisabledDictationMenuItem"];
	[[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"NSDisabledCharacterPaletteMenuItem"];

	// Remove (don't have) the "Enter Full Screen" menu item from the "View" menu
	[[NSUserDefaults standardUserDefaults] setBool:NO forKey:@"NSFullScreenMenuItemEverywhere"];
}

static PyObject*
disable_cocoa_ui_elements(PyObject *self, PyObject *args) {
	PyObject *tabbing = Py_True, *menu_items = Py_True;
	if (!PyArg_ParseTuple(args, "|OO", &tabbing, &menu_items)) return NULL;
	if (PyObject_IsTrue(tabbing)) disable_window_tabbing();
	if (PyObject_IsTrue(menu_items)) remove_cocoa_menu_items();
	Py_RETURN_NONE;
}


static PyObject*
enable_cocoa_multithreading(PyObject *self, PyObject *args) {
	if (![NSThread isMultiThreaded]) [[NSThread new] start];
	Py_RETURN_NONE;
}


static PyObject*
send2trash(PyObject *self, PyObject *args) {
	(void)self;
	char *path = NULL;
    if (!PyArg_ParseTuple(args, "s", &path)) return NULL;
	@autoreleasepool {
		NSError* ns_error = nil;
		if (![[NSFileManager defaultManager] trashItemAtURL:[NSURL fileURLWithPath:@(path)] resultingItemURL:nil error:&ns_error]) {
			PyErr_SetString(PyExc_OSError, [[ns_error localizedDescription] UTF8String]);
		}
	}
	if (PyErr_Occurred()) return NULL;
	Py_RETURN_NONE;
}

// Notifications {{{
static PyObject *notification_activated_callback = NULL;

@interface NotificationDelegate : NSObject <UNUserNotificationCenterDelegate>
@end

@implementation NotificationDelegate
    - (void)userNotificationCenter:(UNUserNotificationCenter *)center
            willPresentNotification:(UNNotification *)notification
            withCompletionHandler:(void (^)(UNNotificationPresentationOptions))completionHandler {
        (void)(center); (void)notification;
        UNNotificationPresentationOptions options = UNNotificationPresentationOptionSound;
        options |= UNNotificationPresentationOptionList | UNNotificationPresentationOptionBanner;
        completionHandler(options);
    }

    - (void)userNotificationCenter:(UNUserNotificationCenter *)center
            didReceiveNotificationResponse:(UNNotificationResponse *)response
            withCompletionHandler:(void (^)(void))completionHandler {
        (void)(center);
        if (notification_activated_callback) {
            NSString *identifier = [[[response notification] request] identifier];
            PyObject *ret = PyObject_CallFunction(notification_activated_callback, "z",
                    identifier ? [identifier UTF8String] : NULL);
            if (ret == NULL) PyErr_Print();
            else Py_DECREF(ret);
        }
        completionHandler();
    }
@end


static PyObject*
set_notification_activated_callback(PyObject *self, PyObject *callback) {
    (void)self;
    Py_XDECREF(notification_activated_callback);
    notification_activated_callback = callback;
    Py_INCREF(callback);
    Py_RETURN_NONE;

}

static void
schedule_notification(const char *identifier, const char *title, const char *body, const char *subtitle, bool use_sound) {
    UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
    if (!center) return;
    // Configure the notification's payload.
    UNMutableNotificationContent* content = [[UNMutableNotificationContent alloc] init];
    if (title) content.title = @(title);
    if (body) content.body = @(body);
    if (subtitle) content.subtitle = @(subtitle);
    if (use_sound) content.sound = [UNNotificationSound defaultSound];
    // Deliver the notification
    static unsigned long counter = 1;
    UNNotificationRequest* request = [
        UNNotificationRequest requestWithIdentifier:(identifier ? @(identifier) : [NSString stringWithFormat:@"Id_%lu", counter++])
        content:content trigger:nil];
    [center addNotificationRequest:request withCompletionHandler:^(NSError * _Nullable error) {
        if (error != nil) {
            fprintf(stderr, "Failed to show notification: %s\n", [[error localizedDescription] UTF8String]);
        }
    }];
    [content release];
}

typedef struct {
    char *identifier, *title, *body, *subtitle;
    bool use_sound;
} QueuedNotification;

typedef struct {
    QueuedNotification *notifications;
    size_t count, capacity;
} NotificationQueue;
static NotificationQueue notification_queue = {0};

#define ensure_space_for(base, array, type, num, capacity, initial_cap, zero_mem) \
    if ((base)->capacity < num) { \
        size_t _newcap = MAX((size_t)initial_cap, MAX(2 * (base)->capacity, (size_t)num)); \
        (base)->array = realloc((base)->array, sizeof(type) * _newcap); \
        if (zero_mem) memset((base)->array + (base)->capacity, 0, sizeof(type) * (_newcap - (base)->capacity)); \
        (base)->capacity = _newcap; \
    }


static void
queue_notification(const char *identifier, const char *title, const char* body, const char* subtitle, bool use_sound) {
    ensure_space_for((&notification_queue), notifications, QueuedNotification, notification_queue.count + 16, capacity, 16, true);
    QueuedNotification *n = notification_queue.notifications + notification_queue.count++;
    n->identifier = identifier ? strdup(identifier) : NULL;
    n->title = title ? strdup(title) : NULL;
    n->body = body ? strdup(body) : NULL;
    n->subtitle = subtitle ? strdup(subtitle) : NULL;
    n->use_sound = use_sound;
}

static void
drain_pending_notifications(BOOL granted) {
    if (granted) {
        for (size_t i = 0; i < notification_queue.count; i++) {
            QueuedNotification *n = notification_queue.notifications + i;
            schedule_notification(n->identifier, n->title, n->body, n->subtitle, n->use_sound);
        }
    }
    while(notification_queue.count) {
        QueuedNotification *n = notification_queue.notifications + --notification_queue.count;
        free(n->identifier); free(n->title); free(n->body); free(n->subtitle);
        n->identifier = NULL; n->title = NULL; n->body = NULL; n->subtitle = NULL;
    }
}


static PyObject*
send_notification(PyObject *self, PyObject *args) {
	(void)self;
    char *identifier = NULL, *title = NULL, *subtitle = NULL, *informativeText = NULL;
    int use_sound = 0;
    if (!PyArg_ParseTuple(args, "zsz|pz", &identifier, &title, &informativeText, &use_sound, &subtitle)) return NULL;

    UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
    if (!center) Py_RETURN_NONE;
    if (!center.delegate) center.delegate = [[NotificationDelegate alloc] init];
    queue_notification(identifier, title, informativeText, subtitle, use_sound ? YES : NO);

    // The badge permission needs to be requested as well, even though it is not used,
    // otherwise macOS refuses to show the preference checkbox for enable/disable notification sound.
    [center requestAuthorizationWithOptions:(UNAuthorizationOptionAlert | UNAuthorizationOptionSound | UNAuthorizationOptionBadge)
        completionHandler:^(BOOL granted, NSError * _Nullable error) {
            if (error != nil) {
                fprintf(stderr, "Failed to request permission for showing notification: %s\n", [[error localizedDescription] UTF8String]);
            }
            dispatch_async(dispatch_get_main_queue(), ^{
                drain_pending_notifications(granted);
            });
        }
    ];
    Py_RETURN_NONE;
}
// }}}


static PyObject*
cursor_blink_time(PyObject *self) {
    (void)self;
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    double on_period_ms = [defaults doubleForKey:@"NSTextInsertionPointBlinkPeriodOn"];
    double off_period_ms = [defaults doubleForKey:@"NSTextInsertionPointBlinkPeriodOff"];
    double period_ms = [defaults doubleForKey:@"NSTextInsertionPointBlinkPeriod"];
    double max_value = 60 * 1000.0, ans = -1.0;
    if (on_period_ms || off_period_ms) {
        ans = on_period_ms + off_period_ms;
    } else if (period_ms) {
        ans = period_ms;
    }
	if (ans > max_value) ans = 0.0;
    return PyFloat_FromDouble(ans);
}

static PyObject*
transient_scroller(PyObject *self) {
    (void)self;
    return PyBool_FromLong([NSScroller preferredScrollerStyle] == NSScrollerStyleOverlay);
}

static PyObject*
locale_names(PyObject *self, PyObject *args) {
	PyObject *ans = PyTuple_New(PyTuple_GET_SIZE(args));
	if (!ans) return NULL;
	NSLocale *locale = [NSLocale autoupdatingCurrentLocale];

	for (Py_ssize_t i = 0; i < PyTuple_GET_SIZE(ans); i++) {
		PyObject *x = PyTuple_GET_ITEM(args, i);
		if (!PyUnicode_Check(x)) { PyErr_SetString(PyExc_TypeError, "language codes must be unicode"); Py_CLEAR(ans); return NULL; }
		if (PyUnicode_READY(x) != 0) { Py_CLEAR(ans); return NULL; }
		const char *code = PyUnicode_AsUTF8(x);
		if (code == NULL) { Py_CLEAR(ans); return NULL; }
		NSString *display_name = [locale displayNameForKey:NSLocaleIdentifier value:@(code)];
		if (display_name) {
			PyObject *p = PyUnicode_FromString([display_name UTF8String]);
			if (!p) { Py_CLEAR(ans); return NULL; }
			PyTuple_SET_ITEM(ans, i, p);
		} else {
			Py_INCREF(x);
			PyTuple_SET_ITEM(ans, i, x);
		}
	}
	return ans;
}

static PyObject*
create_io_pm_assertion(PyObject *self, PyObject *args) {
	const char *type, *reason;
	int on = 1;
	if (!PyArg_ParseTuple(args, "ss|p", &type, &reason, &on)) return NULL;
	IOPMAssertionID assertionID;
    CFStringRef s = CFStringCreateWithCString(NULL, type, kCFStringEncodingUTF8);
    if (s == nil) { PyErr_SetString(PyExc_TypeError, "type argument must be a valid UTF-8 string"); return NULL; }
    CFStringRef r = CFStringCreateWithCString(NULL, reason, kCFStringEncodingUTF8);
    if (r == nil) { CFRelease(s); PyErr_SetString(PyExc_TypeError, "reason argument must be a valid UTF-8 string"); return NULL; }
	IOReturn rc = IOPMAssertionCreateWithName(s, on ? kIOPMAssertionLevelOn : kIOPMAssertionLevelOff, r, &assertionID);
    CFRelease(s); CFRelease(r);
	if (rc == kIOReturnSuccess) {
		unsigned long long aid = assertionID;
		return PyLong_FromUnsignedLongLong(aid);
	}
	PyErr_SetString(PyExc_OSError, mach_error_string(rc));
	return NULL;
}

static PyObject*
release_io_pm_assertion(PyObject *self, PyObject *args) {
	unsigned long long aid;
	if (!PyArg_ParseTuple(args, "K", &aid)) return NULL;
	IOReturn rc = IOPMAssertionRelease(aid);
	if (rc == kIOReturnSuccess) { Py_RETURN_NONE; }
	PyErr_SetString(PyExc_OSError, mach_error_string(rc));
	return NULL;
}

static PyObject*
set_requires_aqua_system_appearance(PyObject *self, PyObject *yes) {
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    if (PyObject_IsTrue(yes)) {
        [defaults setBool:YES forKey:@"NSRequiresAquaSystemAppearance"];
    } else {
        if (yes == Py_None) [defaults removeObjectForKey:@"NSRequiresAquaSystemAppearance"];
        else [defaults setBool:NO forKey:@"NSRequiresAquaSystemAppearance"];
    }
    Py_RETURN_NONE;
}

static PyObject*
get_requires_aqua_system_appearance(PyObject *self, PyObject *unused) {
    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
    if ([defaults objectForKey:@"NSRequiresAquaSystemAppearance"]) {
        if ([defaults boolForKey:@"NSRequiresAquaSystemAppearance"]) { Py_RETURN_TRUE; }
        Py_RETURN_FALSE;
    }
    Py_RETURN_NONE;
}

static PyObject*
set_appearance(PyObject *self, PyObject *args) {
    const char *val;
    if (!PyArg_ParseTuple(args, "s", &val)) return NULL;
    [NSApplication sharedApplication];
    if (strcmp(val, "system") == 0) {
        NSApp.appearance = nil;
    } else if (strcmp(val, "light") == 0) {
        NSApp.appearance = [NSAppearance appearanceNamed:NSAppearanceNameAqua];
    }  else if (strcmp(val, "dark") == 0) {
        NSApp.appearance = [NSAppearance appearanceNamed:NSAppearanceNameDarkAqua];
    } else {
        PyErr_Format(PyExc_KeyError, "Unknown appearance type: %s", val);
        return NULL;
    }
    Py_RETURN_NONE;

}

static PyObject*
get_appearance(PyObject *self, PyObject *args) {
    int effective = 0;
    if (!PyArg_ParseTuple(args, "|p", &effective)) return NULL;
    [NSApplication sharedApplication];
    if (effective) {
        if (!NSApp.effectiveAppearance) return PyUnicode_FromString("");
        return PyUnicode_FromString([NSApp.effectiveAppearance.name UTF8String]);
    }
    if (!NSApp.appearance) return PyUnicode_FromString("");
    return PyUnicode_FromString([NSApp.appearance.name UTF8String]);
}


static PyMethodDef module_methods[] = {
    {"get_appearance", (PyCFunction)get_appearance, METH_VARARGS, ""},
    {"set_appearance", (PyCFunction)set_appearance, METH_VARARGS, ""},
    {"set_requires_aqua_system_appearance", (PyCFunction)set_requires_aqua_system_appearance, METH_O, ""},
    {"get_requires_aqua_system_appearance", (PyCFunction)get_requires_aqua_system_appearance, METH_NOARGS, ""},
    {"transient_scroller", (PyCFunction)transient_scroller, METH_NOARGS, ""},
    {"cursor_blink_time", (PyCFunction)cursor_blink_time, METH_NOARGS, ""},
    {"enable_cocoa_multithreading", (PyCFunction)enable_cocoa_multithreading, METH_NOARGS, ""},
    {"set_notification_activated_callback", (PyCFunction)set_notification_activated_callback, METH_O, ""},
    {"send_notification", (PyCFunction)send_notification, METH_VARARGS, ""},
    {"disable_cocoa_ui_elements", (PyCFunction)disable_cocoa_ui_elements, METH_VARARGS, ""},
    {"send2trash", (PyCFunction)send2trash, METH_VARARGS, ""},
    {"locale_names", (PyCFunction)locale_names, METH_VARARGS, ""},
    {"create_io_pm_assertion", (PyCFunction)create_io_pm_assertion, METH_VARARGS, ""},
    {"release_io_pm_assertion", (PyCFunction)release_io_pm_assertion, METH_VARARGS, ""},
    {NULL, NULL, 0, NULL}        /* Sentinel */
};

static int
exec_module(PyObject *module) {
#define A(which) if (PyModule_AddStringConstant(module, #which, [(__bridge NSString *)which UTF8String]) == -1) return -1;
	A(kIOPMAssertionTypePreventUserIdleSystemSleep);
	A(kIOPMAssertionTypePreventUserIdleDisplaySleep);
	A(kIOPMAssertionTypePreventSystemSleep);
	A(kIOPMAssertionTypeNoIdleSleep);
	A(kIOPMAssertionTypeNoDisplaySleep);
#undef A
	return 0;
}

static PyModuleDef_Slot slots[] = { {Py_mod_exec, exec_module}, {0, NULL} };

static struct PyModuleDef module_def = {
    .m_base     = PyModuleDef_HEAD_INIT,
    .m_name     = "cocoa",
    .m_methods  = module_methods,
    .m_slots    = slots,
};

CALIBRE_MODINIT_FUNC PyInit_cocoa(void) {
	return PyModuleDef_Init(&module_def);
}
