/*
 * Copyright (c) 2011 Benjamin Franzke
 * 
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 * 
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial eventions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

#define _GNU_SOURCE

#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <stdint.h>

#include <WF/wfd.h>
#include <WF/wfdext.h>

#include "wflist.h"
#include "wfhandle.h"
#include "wfdregistry.h"
#include "wfdevent.h"
#include "wfdport.h"
#include "wfdpipeline.h"

#include <xf86drm.h>
#include <libudev.h>

#include <sys/epoll.h>
#include <sys/eventfd.h>
#include <sys/time.h>
#include <unistd.h>
#include <fcntl.h>

struct bind_event {
	WFDint pipeline_id;
	WFDSource source;
	WFDint time;

	struct wf_list link;
};

#define EGL_EGLEXT_PROTOTYPES
#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <pthread.h>

struct wfd_event {
	uint32_t start_time_msec;
	int epoll_fd;
	uint32_t filter;

	struct wfd_device *device;

	/* source bind complete */
	int drm_fd;
	struct bind_event bind;

	/* port attach */
	struct udev_monitor *udev_monitor;
	int udev_monitor_fd;
	WFDint attach_port_id;
	WFDboolean attach_state;

	int source_bind_event_queue_fd;
	struct wf_list bind_event_queue;

	WFDEventType current_event_type;

	EGLDisplay egl_display;
	EGLSyncKHR egl_sync;
	pthread_t thread;
	int thread_destroy_fd;
};

static int
create_port_attach_event_fd(struct wfd_event *event)
{
	struct wfd_registry *registry = wfd_get_registry();

	event->udev_monitor =
		udev_monitor_new_from_netlink(registry->udev, "udev");
	if (event->udev_monitor == NULL) {
		fprintf(stderr, "failed to create udev monitor\n");
		return -1;
	}

	udev_monitor_filter_add_match_subsystem_devtype(event->udev_monitor,
							"drm", NULL);

	if (udev_monitor_enable_receiving(event->udev_monitor) < 0) {
		fprintf(stderr, "failed to enable udev-monitor receiving\n");
		udev_monitor_unref(event->udev_monitor);
		return -1;
	}

	return udev_monitor_get_fd(event->udev_monitor);
}

enum wfd_event_type_mask {
	WFD_EVENT_NONE_MASK				= (1 << 0),
	WFD_EVENT_DESTROYED_MASK			= (1 << 1),
	WFD_EVENT_PORT_ATTACH_DETACH_MASK		= (1 << 2),
	WFD_EVENT_PORT_PROTECTION_FAILURE_MASK		= (1 << 3),
	WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE_MASK	= (1 << 4),
	WFD_EVENT_PIPELINE_BIND_MASK_COMPLETE_MASK	= (1 << 5),

	WFD_EVENT_ALL_MASK 				= 0x3f,
};

static int
wfd_event_update(struct wfd_device *device,
		 struct wfd_event *event,
		 uint32_t filter)
{
	struct epoll_event ep;
	uint32_t additions, removals;
	int ret;

	additions =  filter & ~event->filter;
	removals  = ~filter &  event->filter;

	if (additions & WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE_MASK) {
		memset(&ep, 0, sizeof ep);
		ep.events = EPOLLIN;
		event->drm_fd = fcntl(wfd_device_get_fd(device),
				      F_DUPFD_CLOEXEC, 0);
		if (event->drm_fd < 0) {
			fprintf(stderr, "failed to dup drm fd: %m\n");
			return -1;
		}
		ep.data.fd = event->drm_fd;
		ret = epoll_ctl(event->epoll_fd, EPOLL_CTL_ADD,
				ep.data.fd, &ep);
		if (ret == -1) {
			fprintf(stderr, "failed to add fd to epoll: %m\n");
			close(event->drm_fd);
			return -1;
		}

		memset(&ep, 0, sizeof ep);
		event->source_bind_event_queue_fd =
			eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK | EFD_SEMAPHORE);
		ep.events = EPOLLIN;
		ep.data.fd = event->source_bind_event_queue_fd;
		ret = epoll_ctl(event->epoll_fd, EPOLL_CTL_ADD,
				ep.data.fd, &ep);
		if (ret == -1) {
			fprintf(stderr, "failed to add fd to epoll: %m\n");
			return -1;
		}

		wf_list_init(&event->bind_event_queue);

		event->filter |= WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE_MASK;
	} else if (removals & WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE_MASK) {
		ret = epoll_ctl(event->epoll_fd, EPOLL_CTL_DEL,
				event->drm_fd, NULL);
		if (ret) {
			fprintf(stderr, "failed to del fd form epoll: %m\n");
			return -1;
		}

		close (event->drm_fd);

		ret = epoll_ctl(event->epoll_fd, EPOLL_CTL_DEL,
				event->source_bind_event_queue_fd, NULL);
		if (ret) {
			fprintf(stderr, "failed to del fd form epoll: %m\n");
			return -1;
		}
		close(event->source_bind_event_queue_fd);
		
		struct bind_event *entry, *next;
		wf_list_for_each_safe(entry, next,
				      &event->bind_event_queue, link) {
			wf_list_remove(&entry->link);
			free(entry);

		}
		event->filter &= ~WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE_MASK;
	}

	if (additions & WFD_EVENT_PORT_ATTACH_DETACH) {
		memset(&ep, 0, sizeof ep);
		ep.events = EPOLLIN;
		event->udev_monitor_fd = create_port_attach_event_fd(event);
		if (event->udev_monitor_fd < 0) {
			fprintf(stderr, "failed to create udev monitor fd\n");
			return -1;
		}
		ep.data.fd = event->udev_monitor_fd;
		if (ep.data.fd >= 0) {
			ret = epoll_ctl(event->epoll_fd, EPOLL_CTL_ADD,
					ep.data.fd, &ep);
			if (ret == -1) {
				fprintf(stderr, "failed to add fd to epoll: %m\n");
				return -1;
			}
		}

		event->filter |= WFD_EVENT_PORT_ATTACH_DETACH;
	} else if (removals & WFD_EVENT_PORT_ATTACH_DETACH) {
		ret = epoll_ctl(event->epoll_fd, EPOLL_CTL_DEL,
				event->udev_monitor_fd, NULL);
		if (ret) {
			fprintf(stderr, "failed to del fd form epoll: %m\n");
			return -1;
		}

		udev_monitor_unref(event->udev_monitor);
		event->udev_monitor_fd = -1;

		event->filter &= ~WFD_EVENT_PORT_ATTACH_DETACH;
	}

	return 0;
}

void
wfd_event_set_filter(struct wfd_device *device,
		     struct wfd_event *event,
		     const WFDEventType *filter_list)
{
	uint32_t filter;
	int i;

	/* These events cant be disabled */
	filter = WFD_EVENT_NONE_MASK | WFD_EVENT_DESTROYED_MASK;

	if (filter_list == NULL)
		filter |= WFD_EVENT_ALL_MASK;

	for (i = 0; filter_list != NULL && filter_list[i] != WFD_NONE; ++i) {
		switch (filter_list[i]) {
		case WFD_EVENT_NONE:
		case WFD_EVENT_DESTROYED:
		case WFD_EVENT_INVALID:
			break;
		case WFD_EVENT_PORT_ATTACH_DETACH:
			filter |= WFD_EVENT_PORT_ATTACH_DETACH_MASK;
			break;
		case WFD_EVENT_PORT_PROTECTION_FAILURE:
			filter |= WFD_EVENT_PORT_PROTECTION_FAILURE_MASK;
			break;
		case WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE:
			filter |= WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE_MASK;
			break;
		case WFD_EVENT_PIPELINE_BIND_MASK_COMPLETE:
			filter |= WFD_EVENT_PIPELINE_BIND_MASK_COMPLETE_MASK;
			break;
		default:
			wfd_device_set_error(device,
					     WFD_ERROR_ILLEGAL_ARGUMENT);
			return;
		}
	}

	wfd_event_update(device, event, filter);
}

void
wfd_event_destroy(struct wfd_device *device,
		  struct wfd_event *event)
{
	if (event->thread_destroy_fd >= 0) {
		int64_t value = 1;
		write(event->thread_destroy_fd, &value, sizeof value);
		pthread_join(event->thread, NULL);
		close(event->thread_destroy_fd);
		event->thread_destroy_fd = -1;
	}

	wfd_event_update(device, event, 0);

	close(event->epoll_fd);
	free(event);
}

struct wfd_event *
wfd_create_event(struct wfd_device *device,
		 const WFDint *attrib_list)
{
	struct wfd_event *event;
	struct timeval tv;

	event = calloc(1, sizeof *event);
	if (event == NULL)
		return NULL;

	gettimeofday(&tv, NULL);
	event->start_time_msec = tv.tv_sec * 1e3 + tv.tv_usec / 1e3;

	event->epoll_fd = epoll_create1(EPOLL_CLOEXEC);
	if (event->epoll_fd == -1) {
		fprintf(stderr, "failed to crate epoll instance: %m\n");
		free(event);
		return NULL;
	}

	event->device = device;
	event->current_event_type = WFD_EVENT_NONE;
	event->filter = 0;

	event->thread_destroy_fd = -1;

	if (wfd_event_update(device, event, WFD_EVENT_ALL_MASK) < 0) {
		wfd_event_destroy(device, event);
		return NULL;
	}

	return event;
}

WFDint
wfd_event_get_attribi(struct wfd_device *device,
		      struct wfd_event *event,
		      WFDEventAttrib attribute)
{
	switch (attribute) {
	case WFD_EVENT_TYPE:
		return event->current_event_type;
	case WFD_EVENT_PIPELINE_BIND_QUEUE_SIZE:
	case WFD_EVENT_PORT_ATTACH_PORT_ID:
	case WFD_EVENT_PORT_ATTACH_STATE:
	case WFD_EVENT_PORT_PROTECTION_PORT_ID:
	case WFD_EVENT_PIPELINE_BIND_PIPELINE_ID:
	case WFD_EVENT_PIPELINE_BIND_SOURCE:
	case WFD_EVENT_PIPELINE_BIND_MASK:
	case WFD_EVENT_PIPELINE_BIND_QUEUE_OVERFLOW:
	case WFD_EVENT_PIPELINE_BIND_TIME_EXT:
		break;
	default:
		wfd_device_set_error(device, WFD_ERROR_BAD_ATTRIBUTE);
		return 0;
	}

	switch (event->current_event_type) {
	case WFD_EVENT_PORT_ATTACH_DETACH:
		switch (attribute) {
		case WFD_EVENT_PORT_ATTACH_PORT_ID:
			return event->attach_port_id;
		case WFD_EVENT_PORT_ATTACH_STATE:
			return event->attach_state;
		default:
			wfd_device_set_error(device,
					     WFD_ERROR_ILLEGAL_ARGUMENT);
			return 0;
		}

	case WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE:
		switch (attribute) {
		case WFD_EVENT_PIPELINE_BIND_PIPELINE_ID:
			return event->bind.pipeline_id;
		case WFD_EVENT_PIPELINE_BIND_TIME_EXT:
			return event->bind.time;
		case WFD_EVENT_PIPELINE_BIND_SOURCE:
			return event->bind.source;
		default:
			wfd_device_set_error(device,
					     WFD_ERROR_ILLEGAL_ARGUMENT);
			return 0;
		}
	default:
		wfd_device_set_error(device, WFD_ERROR_ILLEGAL_ARGUMENT);
		return 0;
	}
	
	return 0;
}


static struct bind_event global_bind_event;
struct wfd_event *global_event;

static void
page_flip_handler(int fd, unsigned int frame,
		  unsigned int sec, unsigned int usec, void *data)
{
	struct wfd_pipeline *pipeline = data;
	struct bind_event bind;

	wf_list_init(&bind.link);
	bind.source = wf_handle_get(wfd_pipeline_get_previous_source(pipeline),
				    SOURCE_HANDLE);
	bind.pipeline_id = wfd_pipeline_get_id(pipeline);
	bind.time = (sec * 1000 + usec / 1000) -
		global_event->start_time_msec;

	wfd_pipeline_destroy_pending_fb(pipeline);

	if (global_bind_event.pipeline_id == WFD_INVALID_PIPELINE_ID) {
		global_bind_event = bind;
	} else {
		/* queue up */
		int64_t add = 1;
		struct bind_event *queue_entry;

		queue_entry = malloc(sizeof *queue_entry);
		if (queue_entry) {
			*queue_entry = bind;

			wf_list_push_tail(&global_event->bind_event_queue,
					  queue_entry, link);

			if (write(global_event->source_bind_event_queue_fd,
				  &add, sizeof add) < 0) {
				printf("overflow\n");
			}
		}
	}
}

static int
udev_event_is_hotplug_for_device(struct udev_device *u_event,
				 struct wfd_device *device)
{
	struct udev_list_entry *list, *hotplug_entry;
	
	list = udev_device_get_properties_list_entry(u_event);

	hotplug_entry = udev_list_entry_get_by_name(list, "HOTPLUG");
	if (hotplug_entry == NULL)
		return 0;

	if (strcmp(udev_list_entry_get_value(hotplug_entry), "1") != 0)
		return 0;

	if (udev_device_get_devnum(u_event) != 
	    udev_device_get_devnum(wfd_device_get_udev_device(device)))
		return 0;

	return 1;
}

WFDEventType
wfd_event_wait(struct wfd_device *device,
	       struct wfd_event *event,
	       WFDtime time)
{
	struct epoll_event ep;
	WFDEventType event_type = WFD_EVENT_NONE;
	int num;
	int timeout;

	timeout = time / 1e6;

	num = epoll_wait(event->epoll_fd, &ep, 1, timeout);
	if (num == -1) {
		fprintf(stderr, "epoll_wait failed: %m\n");
		return WFD_EVENT_NONE;
	} else if (num == 0) {
		return WFD_EVENT_NONE;
	}

	global_event = event;

	if (ep.data.fd == event->source_bind_event_queue_fd) {
		int64_t id;
		struct bind_event *queue_entry;

		if (read(event->source_bind_event_queue_fd, &id,
			 sizeof id) < 0) {
			fprintf(stderr, "error reading from event queue\n");
			return WFD_EVENT_NONE;
		}

		wf_list_pop_head(&event->bind_event_queue,
				 queue_entry, link);

		event->bind = *queue_entry;
		free(queue_entry);
		event_type = WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE;
	} else if (ep.data.fd == event->drm_fd) {
		drmEventContext drm_evctx;

		memset(&drm_evctx, 0, sizeof drm_evctx);
		drm_evctx.version = DRM_EVENT_CONTEXT_VERSION;
		drm_evctx.page_flip_handler = page_flip_handler;

		global_bind_event.pipeline_id = WFD_INVALID_PIPELINE_ID;
		drmHandleEvent(event->drm_fd, &drm_evctx);
		if (global_bind_event.pipeline_id != WFD_INVALID_PIPELINE_ID) {
			event->bind = global_bind_event;
			event_type = WFD_EVENT_PIPELINE_BIND_SOURCE_COMPLETE;
		}
	} else if (ep.data.fd == event->udev_monitor_fd) {
		struct udev_device *u_event;

		u_event = udev_monitor_receive_device(event->udev_monitor);

		if (udev_event_is_hotplug_for_device(u_event, device)) {
			event_type = wfd_device_find_attach_detach(device,
				&event->attach_port_id, &event->attach_state);
		}

		udev_device_unref(u_event);
	}

	event->current_event_type = event_type;

	return event_type;
}

int
wfd_event_get_fd(struct wfd_device *device,
		 struct wfd_event *event)
{
	return event->epoll_fd;
}

static void *
signalling_thread(void *_event)
{
	struct wfd_event *event = _event;
	struct epoll_event ep[16];
	int i, num;

	while (1) {
		num = epoll_wait(event->epoll_fd, ep, 16, -1);
		if (num < 0)
			continue;
		for (i = 0; i < num; ++i) {
			if (ep[i].data.fd == event->thread_destroy_fd)
				return NULL;
			else
				eglSignalSyncKHR(event->egl_display,
						 event->egl_sync,
						 EGL_SIGNALED_KHR);
		}
	}

	return NULL;
}

int
wfd_event_async(struct wfd_device *device,
		struct wfd_event *event,
		WFDEGLDisplay *egl_display,
		WFDEGLSync *egl_sync)
{
	struct epoll_event ep;

	if (event->egl_sync != NULL)
		return -1;

	event->egl_display = (EGLDisplay) egl_display;
	event->egl_sync = (EGLSyncKHR) egl_sync;

	event->thread_destroy_fd =
		eventfd(0, EFD_CLOEXEC | EFD_NONBLOCK | EFD_SEMAPHORE);

	memset(&ep, 0, sizeof ep);
	ep.events = EPOLLIN;
	ep.data.fd = event->thread_destroy_fd;
	epoll_ctl(event->epoll_fd, EPOLL_CTL_ADD, ep.data.fd, &ep);

	pthread_create(&event->thread, NULL, signalling_thread, event);

	return 0;
}