package org.dolphinemu.dolphinemu.utils;

import android.support.annotation.NonNull;

import org.dolphinemu.dolphinemu.model.settings.BooleanSetting;
import org.dolphinemu.dolphinemu.model.settings.FloatSetting;
import org.dolphinemu.dolphinemu.model.settings.IntSetting;
import org.dolphinemu.dolphinemu.model.settings.Setting;
import org.dolphinemu.dolphinemu.model.settings.SettingSection;
import org.dolphinemu.dolphinemu.model.settings.StringSetting;
import org.dolphinemu.dolphinemu.services.DirectoryInitializationService;
import org.dolphinemu.dolphinemu.ui.settings.SettingsActivityView;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.util.HashMap;
import java.util.Set;
import java.util.TreeSet;

/**
 * A HashMap<String, SettingSection> that constructs a new SettingSection instead of returning null
 * when getting a key not already in the map
 */
final class SettingsSectionMap extends HashMap<String, SettingSection>
{
	@Override
	public SettingSection get(Object key)
	{
		if (!(key instanceof String))
		{
			return null;
		}

		String stringKey = (String)key;

		if (!super.containsKey(stringKey))
		{
			SettingSection section = new SettingSection(stringKey);
			super.put(stringKey, section);
			return section;
		}
		return super.get(key);
	}
}

/**
 * Contains static methods for interacting with .ini files in which settings are stored.
 */
public final class SettingsFile
{
	public static final int SETTINGS_DOLPHIN = 0;
	public static final int SETTINGS_GFX = 1;
	public static final int SETTINGS_WIIMOTE = 2;

	public static final String FILE_NAME_DOLPHIN = "Dolphin";
	public static final String FILE_NAME_GFX = "GFX";
	public static final String FILE_NAME_GCPAD = "GCPadNew";
	public static final String FILE_NAME_WIIMOTE = "WiimoteNew";

	public static final String SECTION_CORE = "Core";

	public static final String SECTION_GFX_SETTINGS = "Settings";
	public static final String SECTION_GFX_ENHANCEMENTS = "Enhancements";
	public static final String SECTION_GFX_HACKS = "Hacks";

	public static final String SECTION_STEREOSCOPY = "Stereoscopy";

	public static final String SECTION_WIIMOTE = "Wiimote";

	public static final String SECTION_BINDINGS = "Android";

	public static final String KEY_CPU_CORE = "CPUCore";
	public static final String KEY_DUAL_CORE = "CPUThread";
	public static final String KEY_OVERCLOCK_ENABLE = "OverclockEnable";
	public static final String KEY_OVERCLOCK_PERCENT = "Overclock";
	public static final String KEY_VIDEO_BACKEND = "GFXBackend";
	public static final String KEY_AUDIO_STRETCH = "AudioStretch";
	public static final String KEY_SLOT_A_DEVICE = "SlotA";
	public static final String KEY_SLOT_B_DEVICE = "SlotB";

	public static final String KEY_SHOW_FPS = "ShowFPS";
	public static final String KEY_INTERNAL_RES = "InternalResolution";
	public static final String KEY_FSAA = "MSAA";
	public static final String KEY_ANISOTROPY = "MaxAnisotropy";
	public static final String KEY_POST_SHADER = "PostProcessingShader";
	public static final String KEY_SCALED_EFB = "EFBScaledCopy";
	public static final String KEY_PER_PIXEL = "EnablePixelLighting";
	public static final String KEY_FORCE_FILTERING = "ForceFiltering";
	public static final String KEY_DISABLE_FOG = "DisableFog";

	public static final String KEY_STEREO_MODE = "StereoMode";
	public static final String KEY_STEREO_DEPTH = "StereoDepth";
	public static final String KEY_STEREO_CONV = "StereoConvergencePercentage";
	public static final String KEY_STEREO_SWAP = "StereoSwapEyes";

	public static final String KEY_SKIP_EFB = "EFBAccessEnable";
	public static final String KEY_IGNORE_FORMAT = "EFBEmulateFormatChanges";
	public static final String KEY_EFB_TEXTURE = "EFBToTextureEnable";
	public static final String KEY_TEXCACHE_ACCURACY = "SafeTextureCacheColorSamples";
	public static final String KEY_GPU_TEXTURE_DECODING = "EnableGPUTextureDecoding";
	public static final String KEY_XFB_TEXTURE = "XFBToTextureEnable";
	public static final String KEY_IMMEDIATE_XFB = "ImmediateXFBEnable";
	public static final String KEY_FAST_DEPTH = "FastDepthCalc";
	public static final String KEY_ASPECT_RATIO = "AspectRatio";
	public static final String KEY_SHADER_COMPILATION_MODE = "ShaderCompilationMode";
	public static final String KEY_WAIT_FOR_SHADERS = "WaitForShadersBeforeStarting";

	public static final String KEY_GCPAD_TYPE = "SIDevice";

	public static final String KEY_GCBIND_A = "InputA_";
	public static final String KEY_GCBIND_B = "InputB_";
	public static final String KEY_GCBIND_X = "InputX_";
	public static final String KEY_GCBIND_Y = "InputY_";
	public static final String KEY_GCBIND_Z = "InputZ_";
	public static final String KEY_GCBIND_START = "InputStart_";
	public static final String KEY_GCBIND_CONTROL_UP = "MainUp_";
	public static final String KEY_GCBIND_CONTROL_DOWN = "MainDown_";
	public static final String KEY_GCBIND_CONTROL_LEFT = "MainLeft_";
	public static final String KEY_GCBIND_CONTROL_RIGHT = "MainRight_";
	public static final String KEY_GCBIND_C_UP = "CStickUp_";
	public static final String KEY_GCBIND_C_DOWN = "CStickDown_";
	public static final String KEY_GCBIND_C_LEFT = "CStickLeft_";
	public static final String KEY_GCBIND_C_RIGHT = "CStickRight_";
	public static final String KEY_GCBIND_TRIGGER_L = "InputL_";
	public static final String KEY_GCBIND_TRIGGER_R = "InputR_";
	public static final String KEY_GCBIND_DPAD_UP = "DPadUp_";
	public static final String KEY_GCBIND_DPAD_DOWN = "DPadDown_";
	public static final String KEY_GCBIND_DPAD_LEFT = "DPadLeft_";
	public static final String KEY_GCBIND_DPAD_RIGHT = "DPadRight_";

	public static final String KEY_GCADAPTER_RUMBLE = "AdapterRumble";
	public static final String KEY_GCADAPTER_BONGOS = "SimulateKonga";

	public static final String KEY_WIIMOTE_TYPE = "Source";
	public static final String KEY_WIIMOTE_EXTENSION = "Extension";

	public static final String KEY_WIIBIND_A = "WiimoteA_";
	public static final String KEY_WIIBIND_B = "WiimoteB_";
	public static final String KEY_WIIBIND_1 = "Wiimote1_";
	public static final String KEY_WIIBIND_2 = "Wiimote2_";
	public static final String KEY_WIIBIND_MINUS = "WiimoteMinus_";
	public static final String KEY_WIIBIND_PLUS = "WiimotePlus_";
	public static final String KEY_WIIBIND_HOME = "WiimoteHome_";
	public static final String KEY_WIIBIND_IR_UP = "IRUp_";
	public static final String KEY_WIIBIND_IR_DOWN = "IRDown_";
	public static final String KEY_WIIBIND_IR_LEFT = "IRLeft_";
	public static final String KEY_WIIBIND_IR_RIGHT = "IRRight_";
	public static final String KEY_WIIBIND_IR_FORWARD = "IRForward_";
	public static final String KEY_WIIBIND_IR_BACKWARD = "IRBackward_";
	public static final String KEY_WIIBIND_IR_HIDE = "IRHide_";
	public static final String KEY_WIIBIND_SWING_UP = "SwingUp_";
	public static final String KEY_WIIBIND_SWING_DOWN = "SwingDown_";
	public static final String KEY_WIIBIND_SWING_LEFT = "SwingLeft_";
	public static final String KEY_WIIBIND_SWING_RIGHT = "SwingRight_";
	public static final String KEY_WIIBIND_SWING_FORWARD = "SwingForward_";
	public static final String KEY_WIIBIND_SWING_BACKWARD = "SwingBackward_";
	public static final String KEY_WIIBIND_TILT_FORWARD = "TiltForward_";
	public static final String KEY_WIIBIND_TILT_BACKWARD = "TiltBackward_";
	public static final String KEY_WIIBIND_TILT_LEFT = "TiltLeft_";
	public static final String KEY_WIIBIND_TILT_RIGHT = "TiltRight_";
	public static final String KEY_WIIBIND_TILT_MODIFIER = "TiltModifier_";
	public static final String KEY_WIIBIND_SHAKE_X = "ShakeX_";
	public static final String KEY_WIIBIND_SHAKE_Y = "ShakeY_";
	public static final String KEY_WIIBIND_SHAKE_Z = "ShakeZ_";
	public static final String KEY_WIIBIND_DPAD_UP = "WiimoteUp_";
	public static final String KEY_WIIBIND_DPAD_DOWN = "WiimoteDown_";
	public static final String KEY_WIIBIND_DPAD_LEFT = "WiimoteLeft_";
	public static final String KEY_WIIBIND_DPAD_RIGHT = "WiimoteRight_";
	public static final String KEY_WIIBIND_NUNCHUK_C = "NunchukC_";
	public static final String KEY_WIIBIND_NUNCHUK_Z = "NunchukZ_";
	public static final String KEY_WIIBIND_NUNCHUK_UP = "NunchukUp_";
	public static final String KEY_WIIBIND_NUNCHUK_DOWN = "NunchukDown_";
	public static final String KEY_WIIBIND_NUNCHUK_LEFT = "NunchukLeft_";
	public static final String KEY_WIIBIND_NUNCHUK_RIGHT = "NunchukRight_";
	public static final String KEY_WIIBIND_NUNCHUK_SWING_UP = "NunchukSwingUp_";
	public static final String KEY_WIIBIND_NUNCHUK_SWING_DOWN = "NunchukSwingDown_";
	public static final String KEY_WIIBIND_NUNCHUK_SWING_LEFT = "NunchukSwingLeft_";
	public static final String KEY_WIIBIND_NUNCHUK_SWING_RIGHT = "NunchukSwingRight_";
	public static final String KEY_WIIBIND_NUNCHUK_SWING_FORWARD = "NunchukSwingForward_";
	public static final String KEY_WIIBIND_NUNCHUK_SWING_BACKWARD = "NunchukSwingBackward_";
	public static final String KEY_WIIBIND_NUNCHUK_TILT_FORWARD = "NunchukTiltForward_";
	public static final String KEY_WIIBIND_NUNCHUK_TILT_BACKWARD = "NunchukTiltBackward_";
	public static final String KEY_WIIBIND_NUNCHUK_TILT_LEFT = "NunchukTiltLeft_";
	public static final String KEY_WIIBIND_NUNCHUK_TILT_RIGHT = "NunchukTiltRight_";
	public static final String KEY_WIIBIND_NUNCHUK_TILT_MODIFIER = "NunchukTiltModifier_";
	public static final String KEY_WIIBIND_NUNCHUK_SHAKE_X = "NunchukShakeX_";
	public static final String KEY_WIIBIND_NUNCHUK_SHAKE_Y = "NunchukShakeY_";
	public static final String KEY_WIIBIND_NUNCHUK_SHAKE_Z = "NunchukShakeZ_";
	public static final String KEY_WIIBIND_CLASSIC_A = "ClassicA_";
	public static final String KEY_WIIBIND_CLASSIC_B = "ClassicB_";
	public static final String KEY_WIIBIND_CLASSIC_X = "ClassicX_";
	public static final String KEY_WIIBIND_CLASSIC_Y = "ClassicY_";
	public static final String KEY_WIIBIND_CLASSIC_ZL = "ClassicZL_";
	public static final String KEY_WIIBIND_CLASSIC_ZR = "ClassicZR_";
	public static final String KEY_WIIBIND_CLASSIC_MINUS = "ClassicMinus_";
	public static final String KEY_WIIBIND_CLASSIC_PLUS = "ClassicPlus_";
	public static final String KEY_WIIBIND_CLASSIC_HOME = "ClassicHome_";
	public static final String KEY_WIIBIND_CLASSIC_LEFT_UP = "ClassicLeftStickUp_";
	public static final String KEY_WIIBIND_CLASSIC_LEFT_DOWN = "ClassicLeftStickDown_";
	public static final String KEY_WIIBIND_CLASSIC_LEFT_LEFT = "ClassicLeftStickLeft_";
	public static final String KEY_WIIBIND_CLASSIC_LEFT_RIGHT = "ClassicLeftStickRight_";
	public static final String KEY_WIIBIND_CLASSIC_RIGHT_UP = "ClassicRightStickUp_";
	public static final String KEY_WIIBIND_CLASSIC_RIGHT_DOWN = "ClassicRightStickDown_";
	public static final String KEY_WIIBIND_CLASSIC_RIGHT_LEFT = "ClassicRightStickLeft_";
	public static final String KEY_WIIBIND_CLASSIC_RIGHT_RIGHT = "ClassicRightStickRight_";
	public static final String KEY_WIIBIND_CLASSIC_TRIGGER_L = "ClassicTriggerL_";
	public static final String KEY_WIIBIND_CLASSIC_TRIGGER_R = "ClassicTriggerR_";
	public static final String KEY_WIIBIND_CLASSIC_DPAD_UP = "ClassicUp_";
	public static final String KEY_WIIBIND_CLASSIC_DPAD_DOWN = "ClassicDown_";
	public static final String KEY_WIIBIND_CLASSIC_DPAD_LEFT = "ClassicLeft_";
	public static final String KEY_WIIBIND_CLASSIC_DPAD_RIGHT = "ClassicRight_";
	public static final String KEY_WIIBIND_GUITAR_FRET_GREEN = "GuitarGreen_";
	public static final String KEY_WIIBIND_GUITAR_FRET_RED = "GuitarRed_";
	public static final String KEY_WIIBIND_GUITAR_FRET_YELLOW = "GuitarYellow_";
	public static final String KEY_WIIBIND_GUITAR_FRET_BLUE = "GuitarBlue_";
	public static final String KEY_WIIBIND_GUITAR_FRET_ORANGE = "GuitarOrange_";
	public static final String KEY_WIIBIND_GUITAR_STRUM_UP = "GuitarStrumUp_";
	public static final String KEY_WIIBIND_GUITAR_STRUM_DOWN = "GuitarStrumDown_";
	public static final String KEY_WIIBIND_GUITAR_MINUS = "GuitarMinus_";
	public static final String KEY_WIIBIND_GUITAR_PLUS = "GuitarPlus_";
	public static final String KEY_WIIBIND_GUITAR_STICK_UP = "GuitarUp_";
	public static final String KEY_WIIBIND_GUITAR_STICK_DOWN = "GuitarDown_";
	public static final String KEY_WIIBIND_GUITAR_STICK_LEFT = "GuitarLeft_";
	public static final String KEY_WIIBIND_GUITAR_STICK_RIGHT = "GuitarRight_";
	public static final String KEY_WIIBIND_GUITAR_WHAMMY_BAR = "GuitarWhammy_";
	public static final String KEY_WIIBIND_DRUMS_PAD_RED = "DrumsRed_";
	public static final String KEY_WIIBIND_DRUMS_PAD_YELLOW = "DrumsYellow_";
	public static final String KEY_WIIBIND_DRUMS_PAD_BLUE = "DrumsBlue_";
	public static final String KEY_WIIBIND_DRUMS_PAD_GREEN = "DrumsGreen_";
	public static final String KEY_WIIBIND_DRUMS_PAD_ORANGE = "DrumsOrange_";
	public static final String KEY_WIIBIND_DRUMS_PAD_BASS = "DrumsBass_";
	public static final String KEY_WIIBIND_DRUMS_MINUS = "DrumsMinus_";
	public static final String KEY_WIIBIND_DRUMS_PLUS = "DrumsPlus_";
	public static final String KEY_WIIBIND_DRUMS_STICK_UP = "DrumsUp_";
	public static final String KEY_WIIBIND_DRUMS_STICK_DOWN = "DrumsDown_";
	public static final String KEY_WIIBIND_DRUMS_STICK_LEFT = "DrumsLeft_";
	public static final String KEY_WIIBIND_DRUMS_STICK_RIGHT = "DrumsRight_";
	public static final String KEY_WIIBIND_TURNTABLE_GREEN_LEFT = "TurntableGreenLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_RED_LEFT = "TurntableRedLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_BLUE_LEFT = "TurntableBlueLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_GREEN_RIGHT = "TurntableGreenRight_";
	public static final String KEY_WIIBIND_TURNTABLE_RED_RIGHT = "TurntableRedRight_";
	public static final String KEY_WIIBIND_TURNTABLE_BLUE_RIGHT = "TurntableBlueRight_";
	public static final String KEY_WIIBIND_TURNTABLE_MINUS = "TurntableMinus_";
	public static final String KEY_WIIBIND_TURNTABLE_PLUS = "TurntablePlus_";
	public static final String KEY_WIIBIND_TURNTABLE_EUPHORIA = "TurntableEuphoria_";
	public static final String KEY_WIIBIND_TURNTABLE_LEFT_LEFT = "TurntableLeftLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_LEFT_RIGHT = "TurntableLeftRight_";
	public static final String KEY_WIIBIND_TURNTABLE_RIGHT_LEFT = "TurntableRightLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_RIGHT_RIGHT = "TurntableRightRight_";
	public static final String KEY_WIIBIND_TURNTABLE_STICK_UP = "TurntableUp_";
	public static final String KEY_WIIBIND_TURNTABLE_STICK_DOWN = "TurntableDown_";
	public static final String KEY_WIIBIND_TURNTABLE_STICK_LEFT = "TurntableLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_STICK_RIGHT = "TurntableRight_";
	public static final String KEY_WIIBIND_TURNTABLE_EFFECT_DIAL = "TurntableEffDial_";
	public static final String KEY_WIIBIND_TURNTABLE_CROSSFADE_LEFT = "TurntableCrossLeft_";
	public static final String KEY_WIIBIND_TURNTABLE_CROSSFADE_RIGHT = "TurntableCrossRight_";

	public static final String KEY_WIIMOTE_SCAN = "WiimoteContinuousScanning";
	public static final String KEY_WIIMOTE_SPEAKER = "WiimoteEnableSpeaker";

	// Internal only, not actually found in settings file.
	public static final String KEY_VIDEO_BACKEND_INDEX = "VideoBackendIndex";

	private SettingsFile()
	{
	}

	/**
	 * Reads a given .ini file from disk and returns it as a HashMap of SettingSections, themselves
	 * effectively a HashMap of key/value settings. If unsuccessful, outputs an error telling why it
	 * failed.
	 *
	 * @param fileName The name of the settings file without a path or extension.
	 * @param view     The current view.
	 * @return An Observable that emits a HashMap of the file's contents, then completes.
	 */
	public static HashMap<String, SettingSection> readFile(final String fileName, SettingsActivityView view)
	{
		HashMap<String, SettingSection> sections = new SettingsSectionMap();

		File ini = getSettingsFile(fileName);

		BufferedReader reader = null;

		try
		{
			reader = new BufferedReader(new FileReader(ini));

			SettingSection current = null;
			for (String line; (line = reader.readLine()) != null; )
			{
				if (line.startsWith("[") && line.endsWith("]"))
				{
					current = sectionFromLine(line);
					sections.put(current.getName(), current);
				}
				else if ((current != null))
				{
					Setting setting = settingFromLine(current, line, fileName);
					if (setting != null)
					{
						current.putSetting(setting);
					}
				}
			}
		}
		catch (FileNotFoundException e)
		{
			Log.error("[SettingsFile] File not found: " + fileName + ".ini: " + e.getMessage());
			view.onSettingsFileNotFound();
		}
		catch (IOException e)
		{
			Log.error("[SettingsFile] Error reading from: " + fileName + ".ini: " + e.getMessage());
			view.onSettingsFileNotFound();
		}
		finally
		{
			if (reader != null)
			{
				try
				{
					reader.close();
				}
				catch (IOException e)
				{
					Log.error("[SettingsFile] Error closing: " + fileName + ".ini: " + e.getMessage());
				}
			}
		}

		if (fileName.equals(SettingsFile.FILE_NAME_DOLPHIN))
		{
			addGcPadSettingsIfTheyDontExist(sections);
		}

		return sections;
	}

	/**
	 * Saves a Settings HashMap to a given .ini file on disk. If unsuccessful, outputs an error
	 * telling why it failed.
	 *
	 * @param fileName The target filename without a path or extension.
	 * @param sections The HashMap containing the Settings we want to serialize.
	 * @param view     The current view.
	 * @return An Observable representing the operation.
	 */
	public static void saveFile(final String fileName, final HashMap<String, SettingSection> sections, SettingsActivityView view)
	{
		File ini = getSettingsFile(fileName);

		PrintWriter writer = null;
		try
		{
			writer = new PrintWriter(ini, "UTF-8");

			Set<String> keySet = sections.keySet();
			Set<String> sortedKeySet = new TreeSet<>(keySet);

			for (String key : sortedKeySet)
			{
				SettingSection section = sections.get(key);
				writeSection(writer, section);
			}
		}
		catch (FileNotFoundException e)
		{
			Log.error("[SettingsFile] File not found: " + fileName + ".ini: " + e.getMessage());
			view.showToastMessage("Error saving " + fileName + ".ini: " + e.getMessage());
		}
		catch (UnsupportedEncodingException e)
		{
			Log.error("[SettingsFile] Bad encoding; please file a bug report: " + fileName + ".ini: " + e.getMessage());
			view.showToastMessage("Error saving " + fileName + ".ini: " + e.getMessage());
		}
		finally
		{
			if (writer != null)
			{
				writer.close();
			}
		}
	}

	@NonNull
	private static File getSettingsFile(String fileName)
	{
		return new File(DirectoryInitializationService.getUserDirectory() + "/Config/" + fileName + ".ini");
	}

	private static SettingSection sectionFromLine(String line)
	{
		String sectionName = line.substring(1, line.length() - 1);
		return new SettingSection(sectionName);
	}

	private static void addGcPadSettingsIfTheyDontExist(HashMap<String, SettingSection> sections)
	{
		SettingSection coreSection = sections.get(SettingsFile.SECTION_CORE);

		for (int i = 0; i < 4; i++)
		{
			String key = SettingsFile.KEY_GCPAD_TYPE + i;
			if (coreSection.getSetting(key) == null)
			{
				Setting gcPadSetting = new IntSetting(key, SettingsFile.SECTION_CORE, SettingsFile.SETTINGS_DOLPHIN, 0);
				coreSection.putSetting(gcPadSetting);
			}
		}

		sections.put(SettingsFile.SECTION_CORE, coreSection);
	}

	/**
	 * For a line of text, determines what type of data is being represented, and returns
	 * a Setting object containing this data.
	 *
	 * @param current  The section currently being parsed by the consuming method.
	 * @param line     The line of text being parsed.
	 * @param fileName The name of the ini file the setting is in.
	 * @return A typed Setting containing the key/value contained in the line.
	 */
	private static Setting settingFromLine(SettingSection current, String line, String fileName)
	{
		String[] splitLine = line.split("=");

		if (splitLine.length != 2)
		{
			Log.warning("Skipping invalid config line \"" + line + "\"");
			return null;
		}

		String key = splitLine[0].trim();
		String value = splitLine[1].trim();

		int file;
		switch (fileName)
		{
			case FILE_NAME_GFX:
				file = SETTINGS_GFX;
				break;
			case FILE_NAME_WIIMOTE:
				file = SETTINGS_WIIMOTE;
				break;
			default:
				file = SETTINGS_DOLPHIN;
				break;
		}

		try
		{
			int valueAsInt = Integer.valueOf(value);

			return new IntSetting(key, current.getName(), file, valueAsInt);
		}
		catch (NumberFormatException ex)
		{
		}

		try
		{
			float valueAsFloat = Float.valueOf(value);

			return new FloatSetting(key, current.getName(), file, valueAsFloat);
		}
		catch (NumberFormatException ex)
		{
		}

		switch (value)
		{
			case "True":
				return new BooleanSetting(key, current.getName(), file, true);
			case "False":
				return new BooleanSetting(key, current.getName(), file, false);
			default:
				return new StringSetting(key, current.getName(), file, value);
		}
	}

	/**
	 * Writes the contents of a Section HashMap to disk.
	 *
	 * @param writer A PrintWriter pointed at a file on disk.
	 * @param section A section containing settings to be written to the file.
	 */
	private static void writeSection(PrintWriter writer, SettingSection section)
	{
		// Write the section header.
		String header = sectionAsString(section);
		writer.println(header);

		// Write this section's values.
		HashMap<String, Setting> settings = section.getSettings();
		Set<String> keySet = settings.keySet();
		Set<String> sortedKeySet = new TreeSet<>(keySet);

		for (String key : sortedKeySet)
		{
			Setting setting = settings.get(key);
			String settingString = settingAsString(setting);

			writer.println(settingString);
		}
	}

	private static String sectionAsString(SettingSection section)
	{
		return "[" + section.getName() + "]";
	}

	private static String settingAsString(Setting setting)
	{
		return setting.getKey() + " = " + setting.getValueAsString();
	}
}
