/*
  Copyright 2007-2011 David Robillard <http://drobilla.net>

  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 ``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
  AUTHOR 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.
*/

#define _XOPEN_SOURCE 500

#include <assert.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "suil-config.h"
#include "suil_internal.h"

#define NS_UI       "http://lv2plug.in/ns/extensions/ui#"
#define GTK2_UI_URI NS_UI "GtkUI"
#define QT4_UI_URI  NS_UI "Qt4UI"

SUIL_API
unsigned
suil_ui_supported(const char* container_type_uri,
                  const char* ui_type_uri)
{
	enum {
		SUIL_WRAPPING_UNSUPPORTED = 0,
		SUIL_WRAPPING_NATIVE      = 1,
		SUIL_WRAPPING_EMBEDDED    = 2
	};
	if (!strcmp(container_type_uri, ui_type_uri)) {
		return SUIL_WRAPPING_NATIVE;
	} else if ((!strcmp(container_type_uri, GTK2_UI_URI)
	            && !strcmp(ui_type_uri, QT4_UI_URI))
	           || (!strcmp(container_type_uri, QT4_UI_URI)
	               && !strcmp(ui_type_uri, GTK2_UI_URI))) {
		return SUIL_WRAPPING_EMBEDDED;
	} else {
		return SUIL_WRAPPING_UNSUPPORTED;
	}
}

struct _SuilModule {
	SuilWrapInitFunc init;
	SuilWrapFunc     wrap;
};

typedef struct _SuilModule* SuilModule;

static SuilModule
get_wrap_module(const char* container_type_uri,
                const char* ui_type_uri)
{
	if (!strcmp(container_type_uri, ui_type_uri)) {
		return NULL;
	}

	const char* module_name = NULL;
	if (!strcmp(container_type_uri, QT4_UI_URI)
	    && !strcmp(ui_type_uri, GTK2_UI_URI)) {
		module_name = "libsuil_gtk2_in_qt4";
	} else if (!strcmp(container_type_uri, GTK2_UI_URI)
	    && !strcmp(ui_type_uri, QT4_UI_URI)) {
		module_name = "libsuil_qt4_in_gtk2";
	}

	if (!module_name) {
		SUIL_ERRORF("Unable to wrap UI type <%s> as type <%s>\n",
		            ui_type_uri, container_type_uri);
		return NULL;
	}

	const size_t path_len = strlen(SUIL_MODULE_DIR)
		+ strlen(module_name)
		+ strlen(SUIL_MODULE_EXT)
		+ 2;

	char* const path = calloc(path_len, 1);
	snprintf(path, path_len, "%s%s%s%s",
	         SUIL_MODULE_DIR, SUIL_DIR_SEP, module_name, SUIL_MODULE_EXT);

	// Open wrap module
	dlerror();
	void* lib = dlopen(path, RTLD_NOW);
	if (!lib) {
		SUIL_ERRORF("Unable to open wrap module %s\n", path);
		return NULL;
	}

	SuilModule module = (SuilModule)malloc(sizeof(struct _SuilModule));
	module->init = (SuilWrapInitFunc)suil_dlfunc(lib, "suil_wrap_init");
	module->wrap = (SuilWrapFunc)suil_dlfunc(lib, "suil_wrap");

	if (!module->init || !module->wrap) {
		SUIL_ERRORF("Corrupt module %s\n", path);
		free(path);
		free(module);
		return NULL;
	}

	free(path);

	return module;
}

SUIL_API
SuilInstance
suil_instance_new(SuilHost                  host,
                  SuilController            controller,
                  const char*               container_type_uri,
                  const char*               plugin_uri,
                  const char*               ui_uri,
                  const char*               ui_type_uri,
                  const char*               ui_bundle_path,
                  const char*               ui_binary_path,
                  const LV2_Feature* const* features)
{
	// Open UI library
	dlerror();
	void* lib = dlopen(ui_binary_path, RTLD_NOW);
	if (!lib) {
		SUIL_ERRORF("Unable to open UI library %s (%s)\n",
		            ui_binary_path, dlerror());
		return NULL;
	}

	// Get discovery function
	LV2UI_DescriptorFunction df = (LV2UI_DescriptorFunction)
		suil_dlfunc(lib, "lv2ui_descriptor");
	if (!df) {
		SUIL_ERRORF("Broken LV2 UI %s (no lv2ui_descriptor symbol found)\n",
		            ui_binary_path);
		dlclose(lib);
		return NULL;
	}

	// Get UI descriptor
	const LV2UI_Descriptor* descriptor = NULL;
	for (uint32_t i = 0; true; ++i) {
		const LV2UI_Descriptor* ld = df(i);
		if (!strcmp(ld->URI, ui_uri)) {
			descriptor = ld;
			break;
		}
	}
	if (!descriptor) {
		SUIL_ERRORF("Failed to find descriptor for <%s> in %s\n",
		            ui_uri, ui_binary_path);
		dlclose(lib);
		return NULL;
	}

	// Use empty local features array if necessary
	const LV2_Feature* local_features[1];
	local_features[0] = NULL;
	if (!features) {
		features = (const LV2_Feature* const*)&local_features;
	}

	SuilModule module = get_wrap_module(container_type_uri, ui_type_uri);
	if (module) {
		module->init(container_type_uri, ui_type_uri, features);
	}

	// Instantiate UI
	struct _SuilInstance* instance = malloc(sizeof(struct _SuilInstance));
	instance->lib_handle  = lib;
	instance->descriptor  = descriptor;
	instance->host_widget = NULL;
	instance->ui_widget   = NULL;
	instance->handle      = descriptor->instantiate(
		descriptor,
		plugin_uri,
		ui_bundle_path,
		host->write_func,
		controller,
		&instance->ui_widget,
		features);

	// Failed to find or instantiate UI
	if (!instance || !instance->handle) {
		SUIL_ERRORF("Failed to instantiate UI <%s> in %s\n",
		            ui_uri, ui_binary_path);
		free(instance);
		dlclose(lib);
		return NULL;
	}

	// Got a handle, but failed to create a widget (buggy UI)
	if (!instance->ui_widget) {
		SUIL_ERRORF("Widget creation failed for UI <%s> in %s\n",
		            ui_uri, ui_binary_path);
		suil_instance_free(instance);
		return NULL;
	}

	if (module) {
		if (module->wrap(container_type_uri, ui_type_uri, instance)) {
			SUIL_ERRORF("Failed to wrap UI <%s> in type <%s>\n",
			            ui_uri, container_type_uri);
			suil_instance_free(instance);
			return NULL;
		}
	} else {
		instance->host_widget = instance->ui_widget;
	}

	return instance;
}

SUIL_API
void
suil_instance_free(SuilInstance instance)
{
	if (instance) {
		instance->descriptor->cleanup(instance->handle);
		dlclose(instance->lib_handle);
		free(instance);
	}
}

SUIL_API
const LV2UI_Descriptor*
suil_instance_get_descriptor(SuilInstance instance)
{
	return instance->descriptor;
}

SUIL_API
LV2UI_Handle
suil_instance_get_handle(SuilInstance instance)
{
	return instance->handle;
}

SUIL_API
LV2UI_Widget
suil_instance_get_widget(SuilInstance instance)
{
	return instance->host_widget;
}

SUIL_API
void
suil_instance_port_event(SuilInstance instance,
                         uint32_t     port_index,
                         uint32_t     buffer_size,
                         uint32_t     format,
                         const void*  buffer)
{
	instance->descriptor->port_event(instance->handle,
	                                 port_index,
	                                 buffer_size,
	                                 format,
	                                 buffer);
}

SUIL_API
const void*
suil_instance_extension_data(SuilInstance instance,
                             const char*  uri)
{
	return instance->descriptor->extension_data(uri);
}