/*
 * This source file is part of RmlUi, the HTML/CSS Interface Middleware
 *
 * For the latest information, see http://github.com/mikke89/RmlUi
 *
 * Copyright (c) 2008-2010 CodePoint Ltd, Shift Technology Ltd
 * Copyright (c) 2019 The RmlUi Team, and contributors
 *
 * 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 portions 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.
 *
 */

#include "precompiled.h"
#include "../../Include/RmlUi/Core.h"
#include "EventSpecification.h"
#include "FileInterfaceDefault.h"
#include "GeometryDatabase.h"
#include "PluginRegistry.h"
#include "StyleSheetFactory.h"
#include "TemplateCache.h"
#include "TextureDatabase.h"
#include "EventSpecification.h"

namespace Rml {
namespace Core {

// RmlUi's renderer interface.
static RenderInterface* render_interface = nullptr;
/// RmlUi's system interface.
static SystemInterface* system_interface = nullptr;
// RmlUi's file I/O interface.
static FileInterface* file_interface = nullptr;

// Default interfaces should be created and destroyed on Initialise and Shutdown, respectively.
static std::unique_ptr<FileInterface> default_file_interface;

static bool initialised = false;

using ContextMap = UnorderedMap< String, UniquePtr<Context> >;
static ContextMap contexts;

#ifndef RMLUI_VERSION
	#define RMLUI_VERSION "custom"
#endif


bool Initialise()
{
	// Check for valid interfaces, or install default interfaces as appropriate.
	if (!system_interface)
	{	
		Log::Message(Log::LT_ERROR, "No system interface set!");
		return false;
	}

	if (!file_interface)
	{		
#ifndef RMLUI_NO_FILE_INTERFACE_DEFAULT
		default_file_interface = std::make_unique<FileInterfaceDefault>();
		file_interface = default_file_interface.get();
#else
		Log::Message(Log::LT_ERROR, "No file interface set!");
		return false;
#endif
	}

	Log::Initialise();

	EventSpecificationInterface::Initialize();

	TextureDatabase::Initialise();

	FontDatabase::Initialise();

	StyleSheetSpecification::Initialise();
	StyleSheetFactory::Initialise();

	TemplateCache::Initialise();

	Factory::Initialise();

	// Notify all plugins we're starting up.
	PluginRegistry::NotifyInitialise();

	initialised = true;

	return true;
}

void Shutdown()
{
	// Clear out all contexts, which should also clean up all attached elements.
	contexts.clear();

	// Notify all plugins we're being shutdown.
	PluginRegistry::NotifyShutdown();

	TemplateCache::Shutdown();
	StyleSheetFactory::Shutdown();
	StyleSheetSpecification::Shutdown();
	FontDatabase::Shutdown();
	TextureDatabase::Shutdown();
	Factory::Shutdown();

	Log::Shutdown();

	initialised = false;

	render_interface = nullptr;
	file_interface = nullptr;
	system_interface = nullptr;

	default_file_interface.reset();
}

// Returns the version of this RmlUi library.
String GetVersion()
{
	return RMLUI_VERSION;
}

// Sets the interface through which all RmlUi messages will be routed.
void SetSystemInterface(SystemInterface* _system_interface)
{
	system_interface = _system_interface;
}

// Returns RmlUi's system interface.
SystemInterface* GetSystemInterface()
{
	return system_interface;
}

// Sets the interface through which all rendering requests are made.
void SetRenderInterface(RenderInterface* _render_interface)
{
	render_interface = _render_interface;
}

// Returns RmlUi's render interface.
RenderInterface* GetRenderInterface()
{
	return render_interface;
}

// Sets the interface through which all file I/O requests are made.
void SetFileInterface(FileInterface* _file_interface)
{
	file_interface = _file_interface;
}

// Returns RmlUi's file interface.
FileInterface* GetFileInterface()
{
	return file_interface;
}

// Creates a new element context.
Context* CreateContext(const String& name, const Vector2i& dimensions, RenderInterface* custom_render_interface)
{
	if (!initialised)
		return nullptr;

	if (!custom_render_interface && !render_interface)
	{
		Log::Message(Log::LT_WARNING, "Failed to create context '%s', no render interface specified and no default render interface exists.", name.c_str());
		return nullptr;
	}

	if (GetContext(name))
	{
		Log::Message(Log::LT_WARNING, "Failed to create context '%s', context already exists.", name.c_str());
		return nullptr;
	}

	UniquePtr<Context> new_context = Factory::InstanceContext(name);
	if (!new_context)
	{
		Log::Message(Log::LT_WARNING, "Failed to instance context '%s', instancer returned NULL.", name.c_str());
		return nullptr;
	}

	// Set the render interface on the context, and add a reference onto it.
	if (custom_render_interface)
		new_context->render_interface = custom_render_interface;
	else
		new_context->render_interface = render_interface;

	new_context->SetDimensions(dimensions);
	if (dimensions.x > 0 && dimensions.y > 0)
	{
		// install an orthographic projection, by default
		Matrix4f P = Matrix4f::ProjectOrtho(0, (float)dimensions.x, (float)dimensions.y, 0, -1, 1);
		new_context->ProcessProjectionChange(P);
		// install an identity view, by default
		new_context->ProcessViewChange(Matrix4f::Identity());
	}

	Context* new_context_raw = new_context.get();
	contexts[name] = std::move(new_context);

	PluginRegistry::NotifyContextCreate(new_context_raw);

	return new_context_raw;
}

bool RemoveContext(const String& name)
{
	auto it = contexts.find(name);
	if (it != contexts.end())
	{
		contexts.erase(it);
		return true;
	}
	return false;
}

// Fetches a previously constructed context by name.
Context* GetContext(const String& name)
{
	ContextMap::iterator i = contexts.find(name);
	if (i == contexts.end())
		return nullptr;

	return i->second.get();
}

// Fetches a context by index.
Context* GetContext(int index)
{
	ContextMap::iterator i = contexts.begin();
	int count = 0;

	if (index >= GetNumContexts())
		index = GetNumContexts() - 1;

	while (count < index)
	{
		++i;
		++count;
	}

	if (i == contexts.end())
		return nullptr;

	return i->second.get();
}

// Returns the number of active contexts.
int GetNumContexts()
{
	return (int) contexts.size();
}

// Registers a generic rmlui plugin
void RegisterPlugin(Plugin* plugin)
{
	if (initialised)
		plugin->OnInitialise();

	PluginRegistry::RegisterPlugin(plugin);
}

EventId RegisterEventType(const String& type, bool interruptible, bool bubbles, DefaultActionPhase default_action_phase)
{
	return EventSpecificationInterface::InsertOrReplaceCustom(type, interruptible, bubbles, default_action_phase);
}

// Forces all compiled geometry handles generated by RmlUi to be released.
void ReleaseCompiledGeometries()
{
	GeometryDatabase::ReleaseGeometries();
}

// Forces all texture handles loaded and generated by RmlUi to be released.
void ReleaseTextures()
{
	TextureDatabase::ReleaseTextures();
}

}
}