#include "app.hpp"

extern "C" {
#include "memory.h"
}

#ifdef plat_x11
#include <X11/Xlib.h>
#include <X11/Xutil.h>

#include <stdlib.h>

Key key_from_xkey(unsigned key) {
	switch (key) {
		case 0x61:           return key_A;
		case 0x62:           return key_B;
		case 0x63:           return key_C;
		case 0x64:           return key_D;
		case 0x65:           return key_E;
		case 0x66:           return key_F;
		case 0x67:           return key_G;
		case 0x68:           return key_H;
		case 0x69:           return key_I;
		case 0x6A:           return key_J;
		case 0x6B:           return key_K;
		case 0x6C:           return key_L;
		case 0x6D:           return key_M;
		case 0x6E:           return key_N;
		case 0x6F:           return key_O;
		case 0x70:           return key_P;
		case 0x71:           return key_Q;
		case 0x72:           return key_R;
		case 0x73:           return key_S;
		case 0x74:           return key_T;
		case 0x75:           return key_U;
		case 0x76:           return key_V;
		case 0x77:           return key_W;
		case 0x78:           return key_X;
		case 0x79:           return key_Y;
		case 0x7A:           return key_Z;
		case XK_F1:          return key_f1;
		case XK_F2:          return key_f2;
		case XK_F3:          return key_f3;
		case XK_F4:          return key_f4;
		case XK_F5:          return key_f5;
		case XK_F6:          return key_f6;
		case XK_F7:          return key_f7;
		case XK_F8:          return key_f8;
		case XK_F9:          return key_f9;
		case XK_F10:         return key_f10;
		case XK_F11:         return key_f11;
		case XK_F12:         return key_f12;
		case XK_Down:        return key_down;
		case XK_Left:        return key_left;
		case XK_Right:       return key_right;
		case XK_Up:          return key_up;
		case XK_Escape:      return key_escape;
		case XK_Return:      return key_return;
		case XK_BackSpace:   return key_backspace;
		case XK_Linefeed:    return key_return;
		case XK_Tab:         return key_tab;
		case XK_Delete:      return key_delete;
		case XK_Home:        return key_home;
		case XK_End:         return key_end;
		case XK_Page_Up:     return key_page_up;
		case XK_Page_Down:   return key_page_down;
		case XK_Insert:      return key_insert;
		case XK_Shift_L:     return key_shift;
		case XK_Shift_R:     return key_shift;
		case XK_Control_L:   return key_control;
		case XK_Control_R:   return key_control;
		case XK_Super_L:     return key_super;
		case XK_Super_R:     return key_super;
		case XK_Alt_L:       return key_alt;
		case XK_Alt_R:       return key_alt;
		case XK_space:       return key_space;
		case XK_period:      return key_period;
		case XK_0:           return key_0;
		case XK_1:           return key_1;
		case XK_2:           return key_2;
		case XK_3:           return key_3;
		case XK_4:           return key_4;
		case XK_5:           return key_5;
		case XK_6:           return key_6;
		case XK_7:           return key_7;
		case XK_8:           return key_8;
		case XK_9:           return key_9;
		default:             return key_unknown;
	}
}

struct App_Internal {
	Display* d;
	Window wi;
	Atom wm_delete;

	void init(App* app, const char* name) {
		const int default_w = 1920;
		const int default_h = 1080;
		XWindowAttributes wa;
		XSetWindowAttributes attribs = {
			.event_mask =
				ExposureMask |
				KeyPressMask |
				KeyReleaseMask |
				ButtonPressMask |
				ButtonReleaseMask |
				PointerMotionMask
		};
		Window root;
		Visual* v;
		d = XOpenDisplay(0);
		wm_delete = XInternAtom(
			d,
			"WM_DELETE_WINDOW",
			0
		);
		root = DefaultRootWindow(d);
		v = XDefaultVisual(d, 0);
		wi = XCreateWindow(
			d,
			root,
			0,
			0,
			default_w,
			default_h,
			0,
			0,
			InputOutput,
			v,
			CWEventMask,
			&attribs
		);
		XSetWMProtocols(d, wi, &wm_delete, 1);
		XStoreName(d, wi, name);
		XMapRaised(d, wi);
		XGetWindowAttributes(d, wi, &wa);
		app->w = wa.width;
		app->h = wa.height;
	}

	void begin(App* app) {
		while (XPending(d)) {
			XEvent e;
			KeySym sym;
			Key key;
			int btn;
			XNextEvent(d, &e);
			switch (e.type) {
				case ClientMessage:
					if (
						(Atom)e.xclient.data.l[0] ==
						wm_delete
					) {
						app->running = 0;
					}
					break;
				case MotionNotify:
					app->mx = e.xmotion.x;
					app->my = e.xmotion.y;
					break;
				case ButtonPress:
					switch (e.xbutton.button) {
						case 1:
						case 2:
						case 3:
							app->mbtn_states[e.xbutton.button - 1] |= 
								key_state_pressed |
								key_state_just_pressed;
							break;
						case 4:
							app->scrolly++;
							break;
						case 5:
							app->scrolly--;
							break;
						case 6:
							app->scrollx++;
							break;
						case 7:
							app->scrollx--;
							break;
					}
					break;
				case ButtonRelease:
					switch (e.xbutton.button) {
						case 1:
						case 2:
						case 3:
							btn = e.xbutton.button - 1;
							app->mbtn_states[btn] &= ~key_state_pressed;
							app->mbtn_states[btn] |= key_state_just_released;
							break;
						case 4:
							app->scrolly++;
							break;
						case 5:
							app->scrolly--;
							break;
						case 6:
							app->scrollx++;
							break;
						case 7:
							app->scrollx--;
							break;
					}
					break;
				case KeyPress:
					sym = XLookupKeysym(&e.xkey, 0);
					key = key_from_xkey(sym);
					app->key_states[key] |=
						key_state_pressed |
						key_state_just_pressed;
					break;
				case KeyRelease:
					sym = XLookupKeysym(&e.xkey, 0);
					key = key_from_xkey(sym);
					app->key_states[key] &= ~key_state_pressed;
					app->key_states[key] |= key_state_just_released;
					break;
			}
		}
	}

	void end(App* app) {
		(void)app;
	}
};

#endif

App* App::create(const char* name) {
	App* app;
	App_Internal* i;
	char* mem = (char*)malloc(app_memory_size);
	Arena* a = (Arena*)mem;
	mem += sizeof *a;
	init_arena(a, mem, app_memory_size - sizeof *a);
	app = (App*)arena_alloc(a, sizeof *app + sizeof *i);
	app->running = 0;
	app->arena = a;
	i = (App_Internal*)&app[1];
	i->init(app, name);
	return app;
}

void App::destroy() {
	free(arena);
}

void App::begin() {
	int j;
	App_Internal* i = (App_Internal*)&this[1];
	for (j = 0; j < key_count; j++)
		key_states[j] &= ~(
			key_state_just_pressed | key_state_just_released
		);
	for (j = 0; j < mbtn_count; j++)
		mbtn_states[j] &= ~(
			key_state_just_pressed | key_state_just_released
		);
	i->begin(this);
}

void App::end() {
	App_Internal* i = (App_Internal*)&this[1];
	i->end(this);
}

Key_State App::ks(Key k) {
	return (Key_State)key_states[k];
}

Key_State App::ms(Mbtn k) {
	return (Key_State)mbtn_states[k];
}

bool App::kp(Key k) {
	return key_states[k] & key_state_pressed;
}

bool App::kjp(Key k) {
	return key_states[k] & key_state_just_pressed;
}

bool App::kjr(Key k) {
	return key_states[k] & key_state_just_released;
}

bool App::mp(Mbtn b) {
	return mbtn_states[b] & key_state_pressed;
}

bool App::mjp(Mbtn b) {
	return mbtn_states[b] & key_state_just_pressed;
}

bool App::mjr(Mbtn b) {
	return mbtn_states[b] & key_state_just_released;
}