/* Copyright (C) 2019 Wildfire Games.
 * This file is part of 0 A.D.
 *
 * 0 A.D. is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 2 of the License, or
 * (at your option) any later version.
 *
 * 0 A.D. is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with 0 A.D.  If not, see <http://www.gnu.org/licenses/>.
 */

#include "precompiled.h"

#include "MessageHandler.h"
#include "../GameLoop.h"
#include "../CommandProc.h"

#include "graphics/GameView.h"
#include "graphics/LOSTexture.h"
#include "graphics/MapIO.h"
#include "graphics/MapWriter.h"
#include "graphics/Patch.h"
#include "graphics/Terrain.h"
#include "graphics/TerrainTextureEntry.h"
#include "graphics/TerrainTextureManager.h"
#include "lib/bits.h"
#include "lib/file/vfs/vfs_path.h"
#include "lib/status.h"
#include "maths/MathUtil.h"
#include "ps/CLogger.h"
#include "ps/Filesystem.h"
#include "ps/Game.h"
#include "ps/Loader.h"
#include "ps/World.h"
#include "renderer/Renderer.h"
#include "scriptinterface/ScriptInterface.h"
#include "simulation2/Simulation2.h"
#include "simulation2/components/ICmpPlayer.h"
#include "simulation2/components/ICmpPlayerManager.h"
#include "simulation2/components/ICmpPosition.h"
#include "simulation2/components/ICmpRangeManager.h"
#include "simulation2/components/ICmpTerrain.h"

namespace
{
	void InitGame()
	{
		if (g_Game)
		{
			delete g_Game;
			g_Game = NULL;
		}

		g_Game = new CGame(false);

		// Default to player 1 for playtesting
		g_Game->SetPlayerID(1);
	}

	void StartGame(JS::MutableHandleValue attrs)
	{
		g_Game->StartGame(attrs, "");

		// TODO: Non progressive load can fail - need a decent way to handle this
		LDR_NonprogressiveLoad();

		// Disable fog-of-war - this must be done before starting the game,
		// as visual actors cache their visibility state on first render.
		CmpPtr<ICmpRangeManager> cmpRangeManager(*g_Game->GetSimulation2(), SYSTEM_ENTITY);
		if (cmpRangeManager)
			cmpRangeManager->SetLosRevealAll(-1, true);

		PSRETURN ret = g_Game->ReallyStartGame();
		ENSURE(ret == PSRETURN_OK);
	}
}

namespace AtlasMessage {

QUERYHANDLER(GenerateMap)
{
	try
	{
		InitGame();

		// Random map
		const ScriptInterface& scriptInterface = g_Game->GetSimulation2()->GetScriptInterface();
		JSContext* cx = scriptInterface.GetContext();
		JSAutoRequest rq(cx);

		JS::RootedValue settings(cx);
		scriptInterface.ParseJSON(*msg->settings, &settings);
		scriptInterface.SetProperty(settings, "mapType", "random");

		JS::RootedValue attrs(cx);
		ScriptInterface::CreateObject(
			cx,
			&attrs,
			"mapType", "random",
			"script", *msg->filename,
			"settings", settings);

		StartGame(&attrs);

		msg->status = 0;
	}
	catch (PSERROR_Game_World_MapLoadFailed&)
	{
		// Cancel loading
		LDR_Cancel();

		// Since map generation failed and we don't know why, use the blank map as a fallback

		InitGame();

		const ScriptInterface& scriptInterface = g_Game->GetSimulation2()->GetScriptInterface();
		JSContext* cx = scriptInterface.GetContext();
		JSAutoRequest rq(cx);

		// Set up 8-element array of empty objects to satisfy init
		JS::RootedValue playerData(cx);
		ScriptInterface::CreateArray(cx, &playerData);

		for (int i = 0; i < 8; ++i)
		{
			JS::RootedValue player(cx);
			ScriptInterface::CreateObject(cx, &player);
			scriptInterface.SetPropertyInt(playerData, i, player);
		}

		JS::RootedValue settings(cx);
		ScriptInterface::CreateObject(
			cx,
			&settings,
			"mapType", "scenario",
			"PlayerData", playerData);

		JS::RootedValue attrs(cx);
		ScriptInterface::CreateObject(
			cx,
			&attrs,
			"mapType", "scenario",
			"map", "maps/scenarios/_default",
			"settings", settings);

		StartGame(&attrs);

		msg->status = -1;
	}
}

MESSAGEHANDLER(LoadMap)
{
	InitGame();

	const ScriptInterface& scriptInterface = g_Game->GetSimulation2()->GetScriptInterface();
	JSContext* cx = scriptInterface.GetContext();
	JSAutoRequest rq(cx);

	// Scenario
	CStrW map = *msg->filename;
	CStrW mapBase = map.BeforeLast(L".pmp"); // strip the file extension, if any

	JS::RootedValue attrs(cx);

	ScriptInterface::CreateObject(
		cx,
		&attrs,
		"mapType", "scenario",
		"map", mapBase);

	StartGame(&attrs);
}

MESSAGEHANDLER(ImportHeightmap)
{
	std::vector<u16> heightmap_source;
	if (LoadHeightmapImageOs(*msg->filename, heightmap_source) != INFO::OK)
	{
		LOGERROR("Failed to decode heightmap.");
		return;
	}

	// resize terrain to heightmap size
	// Notice that the number of tiles/pixels per side of the heightmap image is
	// one less than the number of vertices per side of the heightmap.
	CTerrain* terrain = g_Game->GetWorld()->GetTerrain();
	terrain->Resize((sqrt(heightmap_source.size()) - 1) / PATCH_SIZE);

	// copy heightmap data into map
	u16* heightmap = g_Game->GetWorld()->GetTerrain()->GetHeightMap();
	ENSURE(heightmap_source.size() == (std::size_t) SQR(g_Game->GetWorld()->GetTerrain()->GetVerticesPerSide()));
	std::copy(heightmap_source.begin(), heightmap_source.end(), heightmap);

	// update simulation
	CmpPtr<ICmpTerrain> cmpTerrain(*g_Game->GetSimulation2(), SYSTEM_ENTITY);
	if (cmpTerrain)
		cmpTerrain->ReloadTerrain();

	g_Game->GetView()->GetLOSTexture().MakeDirty();
}

MESSAGEHANDLER(SaveMap)
{
	CMapWriter writer;
	VfsPath pathname = VfsPath(*msg->filename).ChangeExtension(L".pmp");
	writer.SaveMap(pathname,
		g_Game->GetWorld()->GetTerrain(),
		g_Renderer.GetWaterManager(), g_Renderer.GetSkyManager(),
		&g_LightEnv, g_Game->GetView()->GetCamera(), g_Game->GetView()->GetCinema(),
		&g_Renderer.GetPostprocManager(),
		g_Game->GetSimulation2());
}

QUERYHANDLER(GetMapSettings)
{
	msg->settings = g_Game->GetSimulation2()->GetMapSettingsString();
}

BEGIN_COMMAND(SetMapSettings)
{
	std::string m_OldSettings, m_NewSettings;

	void SetSettings(const std::string& settings)
	{
		g_Game->GetSimulation2()->SetMapSettings(settings);
	}

	void Do()
	{
		m_OldSettings = g_Game->GetSimulation2()->GetMapSettingsString();
		m_NewSettings = *msg->settings;

		SetSettings(m_NewSettings);
	}

	// TODO: we need some way to notify the Atlas UI when the settings are changed
	//	externally, otherwise this will have no visible effect
	void Undo()
	{
		// SetSettings(m_OldSettings);
	}

	void Redo()
	{
		// SetSettings(m_NewSettings);
	}

	void MergeIntoPrevious(cSetMapSettings* prev)
	{
		prev->m_NewSettings = m_NewSettings;
	}
};
END_COMMAND(SetMapSettings)

MESSAGEHANDLER(LoadPlayerSettings)
{
	g_Game->GetSimulation2()->LoadPlayerSettings(msg->newplayers);
}

QUERYHANDLER(GetMapSizes)
{
	msg->sizes = g_Game->GetSimulation2()->GetMapSizes();
}

QUERYHANDLER(GetRMSData)
{
	msg->data = g_Game->GetSimulation2()->GetRMSData();
}

BEGIN_COMMAND(ResizeMap)
{
	int m_OldTiles, m_NewTiles;

	cResizeMap()
	{
	}

	void MakeDirty()
	{
		CmpPtr<ICmpTerrain> cmpTerrain(*g_Game->GetSimulation2(), SYSTEM_ENTITY);
		if (cmpTerrain)
			cmpTerrain->ReloadTerrain();

		// The LOS texture won't normally get updated when running Atlas
		// (since there's no simulation updates), so explicitly dirty it
		g_Game->GetView()->GetLOSTexture().MakeDirty();
	}

	void ResizeTerrain(int tiles)
	{
		CTerrain* terrain = g_Game->GetWorld()->GetTerrain();

		terrain->Resize(tiles / PATCH_SIZE);

		MakeDirty();
	}

	void Do()
	{
		CmpPtr<ICmpTerrain> cmpTerrain(*g_Game->GetSimulation2(), SYSTEM_ENTITY);
		if (!cmpTerrain)
		{
			m_OldTiles = m_NewTiles = 0;
		}
		else
		{
			m_OldTiles = (int)cmpTerrain->GetTilesPerSide();
			m_NewTiles = msg->tiles;
		}

		ResizeTerrain(m_NewTiles);
	}

	void Undo()
	{
		ResizeTerrain(m_OldTiles);
	}

	void Redo()
	{
		ResizeTerrain(m_NewTiles);
	}
};
END_COMMAND(ResizeMap)

QUERYHANDLER(VFSFileExists)
{
	msg->exists = VfsFileExists(*msg->path);
}

QUERYHANDLER(VFSFileRealPath)
{
	VfsPath pathname(*msg->path);
	if (pathname.empty())
		return;
	OsPath realPathname;
	if (g_VFS->GetRealPath(pathname, realPathname) == INFO::OK)
		msg->realPath = realPathname.string();
}

static Status AddToFilenames(const VfsPath& pathname, const CFileInfo& UNUSED(fileInfo), const uintptr_t cbData)
{
	std::vector<std::wstring>& filenames = *(std::vector<std::wstring>*)cbData;
	filenames.push_back(pathname.string().c_str());
	return INFO::OK;
}

QUERYHANDLER(GetMapList)
{
#define GET_FILE_LIST(path, list) \
	std::vector<std::wstring> list; \
	vfs::ForEachFile(g_VFS, path, AddToFilenames, (uintptr_t)&list, L"*.xml", vfs::DIR_RECURSIVE); \
	msg->list = list;

	GET_FILE_LIST(L"maps/scenarios/", scenarioFilenames);
	GET_FILE_LIST(L"maps/skirmishes/", skirmishFilenames);
	GET_FILE_LIST(L"maps/tutorials/", tutorialFilenames);
#undef GET_FILE_LIST
}

}