// Copyright (c) 2012- PPSSPP Project.

// This program 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, version 2.0 or later versions.

// This program 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 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.

#include "base/logging.h"

#include "gfx_es2/glsl_program.h"
#include "gfx_es2/gl_state.h"
#include "gfx_es2/fbo.h"

#include "input/input_state.h"
#include "ui/ui.h"

#include "Core/Config.h"
#include "Core/CoreTiming.h"
#include "Core/CoreParameter.h"
#include "Core/Core.h"
#include "Core/Host.h"
#include "Core/System.h"
#include "Core/MIPS/MIPS.h"
#include "GPU/GPUState.h"
#include "GPU/GPUInterface.h"
#include "Core/HLE/sceCtrl.h"
#include "Core/Debugger/SymbolMap.h"

#include "GamepadEmu.h"
#include "UIShader.h"

#include "MenuScreens.h"
#include "EmuScreen.h"

EmuScreen::EmuScreen(const std::string &filename) : invalid_(true) {
	CheckGLExtensions();
	std::string fileToStart = filename;
	// This is probably where we should start up the emulated PSP.
	INFO_LOG(BOOT, "Starting up hardware.");

	CoreParameter coreParam;
	coreParam.cpuCore = g_Config.bJit ? CPU_JIT : CPU_INTERPRETER;
	coreParam.gpuCore = GPU_GLES;
	coreParam.enableSound = g_Config.bEnableSound;
	coreParam.fileToStart = fileToStart;
	coreParam.mountIso = "";
	coreParam.startPaused = false;
	coreParam.enableDebugging = false;
	coreParam.printfEmuLog = false;
	coreParam.headLess = false;
#ifndef _WIN32
	if (g_Config.iWindowZoom < 1 || g_Config.iWindowZoom > 2)
		g_Config.iWindowZoom = 1;
#endif
	coreParam.renderWidth = 480 * g_Config.iWindowZoom;
	coreParam.renderHeight = 272 * g_Config.iWindowZoom;
	coreParam.outputWidth = dp_xres;
	coreParam.outputHeight = dp_yres;
	coreParam.pixelWidth = pixel_xres;
	coreParam.pixelHeight = pixel_yres;
	coreParam.useMediaEngine = false;
	std::string error_string;
	if (PSP_Init(coreParam, &error_string)) {
		invalid_ = false;
	} else {
		invalid_ = true;
		errorMessage_ = error_string;
		ERROR_LOG(BOOT, "%s", errorMessage_.c_str());
		return;
	}

	host->BootDone();
	host->UpdateDisassembly();

#ifdef _WIN32
	if (g_Config.bAutoRun) {
		Core_EnableStepping(false);
	} else {
		Core_EnableStepping(true);
	}
#endif

	LayoutGamepad(dp_xres, dp_yres);

	NOTICE_LOG(BOOT, "Loading %s...", fileToStart.c_str());
}

EmuScreen::~EmuScreen() {
	if (!invalid_) {
		// If we were invalid, it would already be shutdown.
		PSP_Shutdown();
	}
}

void EmuScreen::dialogFinished(const Screen *dialog, DialogResult result) {
	if (result == DR_OK) {
		screenManager()->switchScreen(new MenuScreen());
	}
}

void EmuScreen::sendMessage(const char *message, const char *value) {
	// External commands, like from the Windows UI.
	if (!strcmp(message, "pause")) {
		screenManager()->push(new PauseScreen());
	} else if (!strcmp(message, "stop")) {
		screenManager()->switchScreen(new MenuScreen());
	} else if (!strcmp(message, "reset")) {
		PSP_Shutdown();
		std::string resetError;
		if (!PSP_Init(PSP_CoreParameter(), &resetError)) {
			ELOG("Error resetting: %s", resetError.c_str());
			screenManager()->switchScreen(new MenuScreen());
			return;
		}
		host->BootDone();
		host->UpdateDisassembly();
#ifdef _WIN32
		if (g_Config.bAutoRun) {
			Core_EnableStepping(false);
		} else {
			Core_EnableStepping(true);
		}
#endif
	}
}

inline float curve1(float x) {
	const float deadzone = 0.15f;
	const float factor = 1.0f / (1.0f - deadzone);
	if (x > deadzone) {
		return (x - deadzone) * (x - deadzone) * factor;
	} else if (x < -0.1f) {
		return -(x + deadzone) * (x + deadzone) * factor;
	} else {
		return 0.0f;
	}
}

inline float clamp1(float x) {
	if (x > 1.0f) return 1.0f;
	if (x < -1.0f) return -1.0f;
	return x;
}

void EmuScreen::update(InputState &input) {
	globalUIState = UISTATE_INGAME;
	if (errorMessage_.size()) {
		screenManager()->push(new ErrorScreen(
			"Error loading file",
			errorMessage_));
		errorMessage_ = "";
		return;
	}

	if (invalid_)
		return;

	// First translate touches into native pad input.
	if (g_Config.bShowTouchControls)
		UpdateGamepad(input);

	UpdateInputState(&input);

	// Then translate pad input into PSP pad input. Also, add in tilt.
	static const int mapping[12][2] = {
		{PAD_BUTTON_A, CTRL_CROSS},
		{PAD_BUTTON_B, CTRL_CIRCLE},
		{PAD_BUTTON_X, CTRL_SQUARE},
		{PAD_BUTTON_Y, CTRL_TRIANGLE},
		{PAD_BUTTON_UP, CTRL_UP},
		{PAD_BUTTON_DOWN, CTRL_DOWN},
		{PAD_BUTTON_LEFT, CTRL_LEFT},
		{PAD_BUTTON_RIGHT, CTRL_RIGHT},
		{PAD_BUTTON_LBUMPER, CTRL_LTRIGGER},
		{PAD_BUTTON_RBUMPER, CTRL_RTRIGGER},
		{PAD_BUTTON_START, CTRL_START},
		{PAD_BUTTON_SELECT, CTRL_SELECT},
	};

	for (int i = 0; i < 12; i++) {
		if (input.pad_buttons_down & mapping[i][0]) {
			__CtrlButtonDown(mapping[i][1]);
		}
		if (input.pad_buttons_up & mapping[i][0]) {
			__CtrlButtonUp(mapping[i][1]);
		}
	}

	float stick_x = input.pad_lstick_x;
	float stick_y = input.pad_lstick_y;
	// Apply tilt
	if (g_Config.bAccelerometerToAnalogHoriz) {
		// TODO: Deadzone, etc.
		stick_x += clamp1(curve1(input.acc.y) * 2.0f);
		stick_x = clamp1(stick_x);
	}

	__CtrlSetAnalog(stick_x, stick_y);

	if (input.pad_buttons_down & (PAD_BUTTON_MENU | PAD_BUTTON_BACK)) {
		if (g_Config.bBufferedRendering)
			fbo_unbind();
		screenManager()->push(new PauseScreen());
	}
}

void EmuScreen::render() {
	if (invalid_)
		return;

	// Reapply the graphics state of the PSP
	ReapplyGfxState();

	// We just run the CPU until we get to vblank. This will quickly sync up pretty nicely.
	// The actual number of cycles doesn't matter so much here as we will break due to CORE_NEXTFRAME, most of the time hopefully...
	int blockTicks = usToCycles(1000000 / 10);

	// Run until CORE_NEXTFRAME
	while (coreState == CORE_RUNNING) {
		u64 nowTicks = CoreTiming::GetTicks();
		mipsr4k.RunLoopUntil(nowTicks + blockTicks);
	}
	// Hopefully coreState is now CORE_NEXTFRAME
	if (coreState == CORE_NEXTFRAME) {
		// set back to running for the next frame
		coreState = CORE_RUNNING;
	} else if (coreState == CORE_POWERDOWN)	{
		ILOG("SELF-POWERDOWN!");
		screenManager()->switchScreen(new MenuScreen());
	}

	if (invalid_)
		return;

	if (g_Config.bBufferedRendering)
		fbo_unbind();

	UIShader_Prepare();

	uiTexture->Bind(0);

	glstate.viewport.set(0, 0, pixel_xres, pixel_yres);
	glstate.viewport.restore();

	ui_draw2d.Begin(UIShader_Get(), DBMODE_NORMAL);

	if (g_Config.bShowTouchControls)
		DrawGamepad(ui_draw2d);

	DrawWatermark();

	glsl_bind(UIShader_Get());
	ui_draw2d.End();
	ui_draw2d.Flush();


	// Tiled renderers like PowerVR should benefit greatly from this. However - seems I can't call it?
#if defined(USING_GLES2)
	bool hasDiscard = false;  // TODO
	if (hasDiscard) {
		//glDiscardFramebuffer(GL_COLOR_EXT | GL_DEPTH_EXT | GL_STENCIL_EXT);
	}
#endif
}

void EmuScreen::deviceLost() {
	ILOG("EmuScreen::deviceLost()");
	gpu->DeviceLost();
}