/*
** v_font.cpp
** Font management
**
**---------------------------------------------------------------------------
** Copyright 1998-2016 Randy Heit
** Copyright 2005-2019 Christoph Oelckers
** All rights reserved.
**
** 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.
** 3. The name of the author may not be used to endorse or promote products
**    derived from this software without specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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.
**---------------------------------------------------------------------------
**
*/

// HEADER FILES ------------------------------------------------------------

#include <cwctype>
#include <stdlib.h>
#include <string.h>
#include <math.h>

#include "templates.h"
#include "m_swap.h"
#include "v_font.h"
#include "printf.h"
#include "textures.h"
#include "filesystem.h"
#include "cmdlib.h"
#include "sc_man.h"
#include "gstrings.h"
#include "image.h"
#include "utf8.h"
#include "myiswalpha.h"
#include "fontchars.h"
#include "multipatchtexture.h"
#include "texturemanager.h"
#include "i_interface.h"

#include "fontinternals.h"



//==========================================================================
//
// FFont :: FFont
//
// Loads a multi-texture font.
//
//==========================================================================

FFont::FFont (const char *name, const char *nametemplate, const char *filetemplate, int lfirst, int lcount, int start, int fdlump, int spacewidth, bool notranslate, bool iwadonly, bool doomtemplate, GlyphSet *baseGlyphs)
	: FFont(fdlump, name)
{
	int i;
	FTextureID lump;
	char buffer[12];
	DVector2 Scale = { 1, 1 };

	noTranslate = notranslate;
	GlobalKerning = false;
	SpaceWidth = 0;
	FontHeight = 0;
	int FixedWidth = 0;

	TMap<int, FGameTexture*> charMap;
	int minchar = INT_MAX;
	int maxchar = INT_MIN;
	
	// Read the font's configuration.
	// This will not be done for the default fonts, because they are not atomic and the default content does not need it.
	
	TArray<FolderEntry> folderdata;
	if (filetemplate != nullptr)
	{
		FStringf path("fonts/%s/", filetemplate);
		// If a name template is given, collect data from all resource files.
		// For anything else, each folder is being treated as an atomic, self-contained unit and mixing from different glyph sets is blocked.
		fileSystem.GetFilesInFolder(path, folderdata, nametemplate == nullptr);
		
		//if (nametemplate == nullptr)
		{
			FStringf infpath("fonts/%s/font.inf", filetemplate);
			
			unsigned index = folderdata.FindEx([=](const FolderEntry &entry)
			{
				return infpath.CompareNoCase(entry.name) == 0;
			});
			
			if (index < folderdata.Size())
			{
				FScanner sc;
				sc.OpenLumpNum(folderdata[index].lumpnum);
				while (sc.GetToken())
				{
					sc.TokenMustBe(TK_Identifier);
					if (sc.Compare("Kerning"))
					{
						sc.MustGetValue(false);
						GlobalKerning = sc.Number;
					}
					if (sc.Compare("Altfont"))
					{
						sc.MustGetString();
						AltFontName = sc.String;
					}
					else if (sc.Compare("Scale"))
					{
						sc.MustGetValue(true);
						Scale.Y = Scale.X = sc.Float;
						if (sc.CheckToken(','))
						{
							sc.MustGetValue(true);
							Scale.Y = sc.Float;
						}
					}
					else if (sc.Compare("SpaceWidth"))
					{
						sc.MustGetValue(false);
						SpaceWidth = sc.Number;
					}
					else if (sc.Compare("FontHeight"))
					{
						sc.MustGetValue(false);
						FontHeight = sc.Number;
					}
					else if (sc.Compare("CellSize"))
					{
						sc.MustGetValue(false);
						FixedWidth = sc.Number;
						sc.MustGetToken(',');
						sc.MustGetValue(false);
						FontHeight = sc.Number;
					}
					else if (sc.Compare("minluminosity"))
					{
						sc.MustGetValue(false);
						MinLum = (int16_t)clamp(sc.Number, 0, 255);
					}
					else if (sc.Compare("maxluminosity"))
					{
						sc.MustGetValue(false);
						MaxLum = (int16_t)clamp(sc.Number, 0, 255);
					}
					else if (sc.Compare("Translationtype"))
					{
						sc.MustGetToken(TK_Identifier);
						if (sc.Compare("console"))
						{
							TranslationType = 1;
						}
						else if (sc.Compare("standard"))
						{
							TranslationType = 0;
						}
						else
						{
							sc.ScriptError("Unknown translation type %s", sc.String);
						}
					}
				}
			}
		}
	}
	
	if (FixedWidth > 0)
	{
		ReadSheetFont(folderdata, FixedWidth, FontHeight, Scale);
		Type = Folder;
	}
	else
	{
		if (baseGlyphs)
		{
			// First insert everything from the given glyph set.
			GlyphSet::Iterator it(*baseGlyphs);
			GlyphSet::Pair* pair;
			while (it.NextPair(pair))
			{
				if (pair->Value && pair->Value->GetTexelWidth() > 0 && pair->Value->GetTexelHeight() > 0)
				{
					auto position = pair->Key;
					if (position < minchar) minchar = position;
					if (position > maxchar) maxchar = position;
					charMap.Insert(position, pair->Value);
				}
			}
		}
		if (nametemplate != nullptr)
		{
			if (!iwadonly)
			{
				for (i = 0; i < lcount; i++)
				{
					int position = lfirst + i;
					mysnprintf(buffer, countof(buffer), nametemplate, i + start);

					lump = TexMan.CheckForTexture(buffer, ETextureType::MiscPatch);
					if (doomtemplate && lump.isValid() && i + start == 121)
					{ // HACKHACK: Don't load STCFN121 in doom(2), because
					  // it's not really a lower-case 'y' but a '|'.
					  // Because a lot of wads with their own font seem to foolishly
					  // copy STCFN121 and make it a '|' themselves, wads must
					  // provide STCFN120 (x) and STCFN122 (z) for STCFN121 to load as a 'y'.
						FStringf c120(nametemplate, 120);
						FStringf c122(nametemplate, 122);
						if (!TexMan.CheckForTexture(c120, ETextureType::MiscPatch).isValid() ||
							!TexMan.CheckForTexture(c122, ETextureType::MiscPatch).isValid())
						{
							// insert the incorrectly named '|' graphic in its correct position.
							position = 124;
						}
					}
					if (lump.isValid())
					{
						Type = Multilump;
						if (position < minchar) minchar = position;
						if (position > maxchar) maxchar = position;
						charMap.Insert(position, TexMan.GetGameTexture(lump));
					}
				}
			}
			else
			{
				FGameTexture *texs[256] = {};
				if (lcount > 256 - start) lcount = 256 - start;
				for (i = 0; i < lcount; i++)
				{
					TArray<FTextureID> array;
					mysnprintf(buffer, countof(buffer), nametemplate, i + start);

					TexMan.ListTextures(buffer, array, true);
					for (auto entry : array)
					{
						auto tex = TexMan.GetGameTexture(entry, false);
						if (tex && !tex->isUserContent() && tex->GetUseType() == ETextureType::MiscPatch)
						{
							texs[i] = tex;
						}
					}
				}
				if (doomtemplate)
				{
					// Handle the misplaced '|'.
					if (texs[121 - '!'] && !texs[120 - '!'] && !texs[122 - '!'] && !texs[124 - '!'])
					{
						texs[124 - '!'] = texs[121 - '!'];
						texs[121 - '!'] = nullptr;
					}
				}

				for (i = 0; i < lcount; i++)
				{
					if (texs[i])
					{
						int position = lfirst + i;
						Type = Multilump;
						if (position < minchar) minchar = position;
						if (position > maxchar) maxchar = position;
						charMap.Insert(position, texs[i]);
					}
				}
			}
		}
		if (folderdata.Size() > 0)
		{
			// all valid lumps must be named with a hex number that represents its Unicode character index.
			for (auto &entry : folderdata)
			{
				char *endp;
				auto base = ExtractFileBase(entry.name);
				auto position = strtoll(base.GetChars(), &endp, 16);
				if ((*endp == 0 || (*endp == '.' && position >= '!' && position < 0xffff)))
				{
					auto lump = TexMan.CheckForTexture(entry.name, ETextureType::MiscPatch);
					if (lump.isValid())
					{
						if ((int)position < minchar) minchar = (int)position;
						if ((int)position > maxchar) maxchar = (int)position;
						auto tex = TexMan.GetGameTexture(lump);
						tex->SetScale((float)Scale.X, (float)Scale.Y);
						charMap.Insert((int)position, tex);
						Type = Folder;
					}
				}
			}
		}
		FirstChar = minchar;
		LastChar = maxchar;
		auto count = maxchar - minchar + 1;
		Chars.Resize(count);
		int fontheight = 0;

		for (i = 0; i < count; i++)
		{
			auto lump = charMap.CheckKey(FirstChar + i);
			if (lump != nullptr)
			{
				auto pic = *lump;
				if (pic != nullptr)
				{
					double fheight = pic->GetDisplayHeight();
					double yoffs = pic->GetDisplayTopOffset();

					int height = int(fheight + abs(yoffs) + 0.5);
					if (height > fontheight)
					{
						fontheight = height;
					}
				}

				auto orig = pic->GetTexture();
				auto tex = MakeGameTexture(orig, nullptr, ETextureType::FontChar); 
				tex->CopySize(pic, true);
				TexMan.AddGameTexture(tex);
				Chars[i].OriginalPic = tex;

				if (sysCallbacks.FontCharCreated) sysCallbacks.FontCharCreated(pic, Chars[i].OriginalPic);

				Chars[i].XMove = (int)Chars[i].OriginalPic->GetDisplayWidth();
			}
			else
			{
				Chars[i].OriginalPic = nullptr;
				Chars[i].XMove = INT_MIN;
			}
		}

		if (SpaceWidth == 0) // An explicit override from the .inf file must always take precedence
		{
			if (spacewidth != -1)
			{
				SpaceWidth = spacewidth;
			}
			else if ('N' - FirstChar >= 0 && 'N' - FirstChar < count && Chars['N' - FirstChar].OriginalPic != nullptr)
			{
				SpaceWidth = (Chars['N' - FirstChar].XMove + 1) / 2;
			}
			else
			{
				SpaceWidth = 4;
			}
		}
		if (FontHeight == 0) FontHeight = fontheight;

		FixXMoves();
	}
}

void FFont::ReadSheetFont(TArray<FolderEntry> &folderdata, int width, int height, const DVector2 &Scale)
{
	// all valid lumps must be named with a hex number that represents the Unicode character index for its first character,
	TArray<TexPartBuild> part(1, true);
	TMap<int, FGameTexture*> charMap;
	int minchar = INT_MAX;
	int maxchar = INT_MIN;
	for (auto &entry : folderdata)
	{
		char *endp;
		auto base = ExtractFileBase(entry.name);
		auto position = strtoll(base.GetChars(), &endp, 16);
		if ((*endp == 0 || (*endp == '.' && position >= 0 && position < 0xffff)))	// Sheet fonts may fill in the low control chars.
		{
			auto lump = TexMan.CheckForTexture(entry.name, ETextureType::MiscPatch);
			if (lump.isValid())
			{
				auto tex = TexMan.GetGameTexture(lump);
				int numtex_x = tex->GetTexelWidth() / width;
				int numtex_y = tex->GetTexelHeight() / height;
				int maxinsheet = int(position) + numtex_x * numtex_y - 1;
				if (minchar > position) minchar = int(position);
				if (maxchar < maxinsheet) maxchar = maxinsheet;

				for (int y = 0; y < numtex_y; y++)
				{
					for (int x = 0; x < numtex_x; x++)
					{
						part[0].OriginX = -width * x;
						part[0].OriginY = -height * y;
						part[0].TexImage = static_cast<FImageTexture*>(tex->GetTexture());
						FMultiPatchTexture *image = new FMultiPatchTexture(width, height, part, false, false);
						FImageTexture *tex = new FImageTexture(image);
						auto gtex = MakeGameTexture(tex, nullptr, ETextureType::FontChar);
						gtex->SetWorldPanning(true);
						gtex->SetOffsets(0, 0, 0);
						gtex->SetOffsets(1, 0, 0);
						gtex->SetScale((float)Scale.X, (float)Scale.Y);
						TexMan.AddGameTexture(gtex);
						charMap.Insert(int(position) + x + y * numtex_x, gtex);
					}
				}
			}
		}
	}


	FirstChar = minchar;
	bool map1252 = false;
	if (minchar < 0x80 && maxchar >= 0xa0) // should be a settable option, but that'd probably cause more problems than it'd solve.
	{
		if (maxchar < 0x2122) maxchar = 0x2122;
		map1252 = true;
	}
	LastChar = maxchar;
	auto count = maxchar - minchar + 1;
	Chars.Resize(count);
	int fontheight = 0;

	for (int i = 0; i < count; i++)
	{
		auto lump = charMap.CheckKey(FirstChar + i);
		if (lump != nullptr)
		{
			auto pic = (*lump)->GetTexture();
			Chars[i].OriginalPic = (*lump)->GetUseType() == ETextureType::FontChar? (*lump) : MakeGameTexture(pic, nullptr, ETextureType::FontChar);
			Chars[i].OriginalPic->SetUseType(ETextureType::FontChar);
			Chars[i].OriginalPic->CopySize(*lump, true);
			if (Chars[i].OriginalPic != *lump) TexMan.AddGameTexture(Chars[i].OriginalPic);
		}
		Chars[i].XMove = int(width / Scale.X);
	}

	if (map1252)
	{
		// Move the Windows-1252 characters to their proper place.
		for (int i = 0x80; i < 0xa0; i++)
		{
			if (win1252map[i - 0x80] != i && Chars[i - minchar].OriginalPic != nullptr && Chars[win1252map[i - 0x80] - minchar].OriginalPic == nullptr)
			{
				std::swap(Chars[i - minchar], Chars[win1252map[i - 0x80] - minchar]);
			}
		}
	}

	SpaceWidth = width;
}

//==========================================================================
//
// FFont :: ~FFont
//
//==========================================================================

FFont::~FFont ()
{
	FFont **prev = &FirstFont;
	FFont *font = *prev;

	while (font != nullptr && font != this)
	{
		prev = &font->Next;
		font = *prev;
	}

	if (font != nullptr)
	{
		*prev = font->Next;
	}
}

//==========================================================================
//
// FFont :: CheckCase
//
//==========================================================================

void FFont::CheckCase()
{
	int lowercount = 0, uppercount = 0;
	for (unsigned i = 0; i < Chars.Size(); i++)
	{
		unsigned chr = i + FirstChar;
		if (lowerforupper[chr] == chr && upperforlower[chr] == chr)
		{
			continue;	// not a letter;
		}
		if (myislower(chr))
		{
			if (Chars[i].OriginalPic != nullptr) lowercount++;
		}
		else
		{
			if (Chars[i].OriginalPic != nullptr) uppercount++;
		}
	}
	if (lowercount == 0) return;	// This is an uppercase-only font and we are done.

	// The ß needs special treatment because it is far more likely to be supplied lowercase only, even in an uppercase font.
	if (Chars[0xdf - FirstChar].OriginalPic != nullptr)
	{
		if (LastChar < 0x1e9e)
		{
			Chars.Resize(0x1e9f - FirstChar);
			LastChar = 0x1e9e;
		}
		if (Chars[0x1e9e - FirstChar].OriginalPic == nullptr)
		{
			std::swap(Chars[0xdf - FirstChar], Chars[0x1e9e - FirstChar]);
			lowercount--;
			uppercount++;
			if (lowercount == 0) return;
		}
	}
}

//==========================================================================
//
// FFont :: FindFont
//
// Searches for the named font in the list of loaded fonts, returning the
// font if it was found. The disk is not checked if it cannot be found.
//
//==========================================================================

FFont *FFont::FindFont (FName name)
{
	if (name == NAME_None)
	{
		return nullptr;
	}
	FFont *font = FirstFont;

	while (font != nullptr)
	{
		if (font->FontName == name) return font;
		font = font->Next;
	}
	return nullptr;
}

//==========================================================================
//
// RecordTextureColors
//
// Given a 256 entry buffer, sets every entry that corresponds to a color
// used by the texture to 1.
//
//==========================================================================

void RecordTextureColors (FImageSource *pic, uint32_t *usedcolors)
{
	int x;
	
	auto pixels = pic->GetPalettedPixels(false);
	auto size = pic->GetWidth() * pic->GetHeight();
	
	for(x = 0;x < size; x++)
	{
		usedcolors[pixels[x]]++;
	}
}

//==========================================================================
//
// RecordLuminosity
//
// Records minimum and maximum luminosity of a texture.
//
//==========================================================================

static void RecordLuminosity(FImageSource* pic, int* minlum, int* maxlum)
{
	auto bitmap = pic->GetCachedBitmap(nullptr, FImageSource::normal);
	auto pixels = bitmap.GetPixels();
	auto size = pic->GetWidth() * pic->GetHeight();

	for (int x = 0; x < size; x++)
	{
		int xx = x * 4;
		if (pixels[xx + 3] > 0)
		{
			int lum = Luminance(pixels[xx + 2], pixels[xx + 1], pixels[xx]);
			if (lum < *minlum) *minlum = lum;
			if (lum > *maxlum) *maxlum = lum;
		}
	}
}

//==========================================================================
//
// RecordAllTextureColors
//
// Given a 256 entry buffer, sets every entry that corresponds to a color
// used by the font.
//
//==========================================================================

void FFont::RecordAllTextureColors(uint32_t *usedcolors)
{
	for (unsigned int i = 0; i < Chars.Size(); i++)
	{
		if (Chars[i].OriginalPic)
		{
			auto pic = Chars[i].OriginalPic->GetTexture()->GetImage();
			if (pic) RecordTextureColors(pic, usedcolors);
		}
	}
}

//==========================================================================
//
// compare
//
// Used for sorting colors by brightness.
//
//==========================================================================

static int compare (const void *arg1, const void *arg2)
{
	if (RPART(GPalette.BaseColors[*((uint8_t *)arg1)]) * 299 +
		GPART(GPalette.BaseColors[*((uint8_t *)arg1)]) * 587 +
		BPART(GPalette.BaseColors[*((uint8_t *)arg1)]) * 114  <
		RPART(GPalette.BaseColors[*((uint8_t *)arg2)]) * 299 +
		GPART(GPalette.BaseColors[*((uint8_t *)arg2)]) * 587 +
		BPART(GPalette.BaseColors[*((uint8_t *)arg2)]) * 114)
		return -1;
	else
		return 1;
}

//==========================================================================
//
// FFont :: GetLuminosity
//
//==========================================================================

int FFont::GetLuminosity (uint32_t *colorsused, TArray<double> &Luminosity, int* minlum, int* maxlum)
{
	double min, max, diver;

	Luminosity.Resize(256);
	Luminosity[0] = 0.0; // [BL] Prevent uninitalized memory
	max = 0.0;
	min = 100000000.0;
	for (int i = 1; i < 256; i++)
	{
		if (colorsused[i])
		{
			Luminosity[i] = GPalette.BaseColors[i].r * 0.299 + GPalette.BaseColors[i].g * 0.587 + GPalette.BaseColors[i].b * 0.114;
			if (Luminosity[i] > max) max = Luminosity[i];
			if (Luminosity[i] < min) min = Luminosity[i];
		}
		else Luminosity[i] = -1;	// this color is not of interest.
	}
	diver = 1.0 / (max - min);
	for (int i = 1; i < 256; i++)
	{
		if (colorsused[i])
		{
			Luminosity[i] = (Luminosity[i] - min) * diver;
		}
	}
	if (minlum) *minlum = int(min);
	if (maxlum) *maxlum = int(max);

	return 256;
}

//==========================================================================
//
// FFont :: GetColorTranslation
//
//==========================================================================

int FFont::GetColorTranslation (EColorRange range, PalEntry *color) const
{
	// Single pic fonts do not set up their translation table and must always return 0.
	if (Translations.Size() == 0) return 0;
	assert(Translations.Size() == (unsigned)NumTextColors);

	if (noTranslate)
	{
		PalEntry retcolor = PalEntry(255, 255, 255, 255);
		if (range >= 0 && range < NumTextColors && range != CR_UNTRANSLATED)
		{
			retcolor = TranslationColors[range];
			retcolor.a = 255;
		}
		if (color != nullptr) *color = retcolor;
	}
	if (range == CR_UNDEFINED)
		return -1;
	else if (range >= NumTextColors)
		range = CR_UNTRANSLATED;
	return Translations[range];
}

//==========================================================================
//
// FFont :: GetCharCode
//
// If the character code is in the font, returns it. If it is not, but it
// is lowercase and has an uppercase variant present, return that. Otherwise
// return -1.
//
//==========================================================================

int FFont::GetCharCode(int code, bool needpic) const
{
	int newcode;

	if (code < 0 && code >= -128)
	{
		// regular chars turn negative when the 8th bit is set.
		code &= 255;
	}
	if (code >= FirstChar && code <= LastChar && (!needpic || Chars[code - FirstChar].OriginalPic != nullptr))
	{
		return code;
	}
	
	// Use different substitution logic based on the fonts content:
	// In a font which has both upper and lower case, prefer unaccented small characters over capital ones.
	// In a pure upper-case font, do not check for lower case replacements.
	if (!MixedCase)
	{
		// Try converting lowercase characters to uppercase.
		if (myislower(code))
		{
			code = upperforlower[code];
			if (code >= FirstChar && code <= LastChar && (!needpic || Chars[code - FirstChar].OriginalPic != nullptr))
			{
				return code;
			}
		}
		// Try stripping accents from accented characters.
		while ((newcode = stripaccent(code)) != code)
		{
			code = newcode;
			if (code >= FirstChar && code <= LastChar && (!needpic || Chars[code - FirstChar].OriginalPic != nullptr))
			{
				return code;
			}
		}
	}
	else
	{
		int originalcode = code;

		// Try stripping accents from accented characters. This may repeat to allow multi-step fallbacks.
		while ((newcode = stripaccent(code)) != code)
		{
			code = newcode;
			if (code >= FirstChar && code <= LastChar && (!needpic || Chars[code - FirstChar].OriginalPic != nullptr))
			{
				return code;
			}
		}

		code = originalcode;
		if (myislower(code))
		{
			int upper = upperforlower[code];
			// Stripping accents did not help - now try uppercase for lowercase
			if (upper != code) return GetCharCode(upper, needpic);
		}

		// Same for the uppercase character. Since we restart at the accented version this must go through the entire thing again.
		while ((newcode = stripaccent(code)) != code)
		{
			code = newcode;
			if (code >= FirstChar && code <= LastChar && (!needpic || Chars[code - FirstChar].OriginalPic != nullptr))
			{
				return code;
			}
		}

	}

	return -1;
}

//==========================================================================
//
// FFont :: GetChar
//
//==========================================================================

FGameTexture *FFont::GetChar (int code, int translation, int *const width) const
{
	code = GetCharCode(code, true);
	int xmove = SpaceWidth;

	if (code >= 0)
	{
		code -= FirstChar;
		xmove = Chars[code].XMove;
	}
	
	if (width != nullptr)
	{
		*width = xmove;
	}
	if (code < 0) return nullptr;


	assert(Chars[code].OriginalPic->GetUseType() == ETextureType::FontChar);
	return Chars[code].OriginalPic;
}

//==========================================================================
//
// FFont :: GetCharWidth
//
//==========================================================================

int FFont::GetCharWidth (int code) const
{
	code = GetCharCode(code, true);
	if (code >= 0) return Chars[code - FirstChar].XMove;
	return SpaceWidth;
}

//==========================================================================
//
// 
//
//==========================================================================

double GetBottomAlignOffset(FFont *font, int c)
{
	int w;
	auto tex_zero = font->GetChar('0', CR_UNDEFINED, &w);
	auto texc = font->GetChar(c, CR_UNDEFINED, &w);
	double offset = 0;
	if (texc) offset += texc->GetDisplayTopOffset();
	if (tex_zero) offset += -tex_zero->GetDisplayTopOffset() + tex_zero->GetDisplayHeight();
	return offset;
}

//==========================================================================
//
// Checks if the font contains proper glyphs for all characters in the string
//
//==========================================================================

bool FFont::CanPrint(const uint8_t *string) const
{
	if (!string) return true;
	while (*string)
	{
		auto chr = GetCharFromString(string);
		if (!MixedCase) chr = upperforlower[chr];	// For uppercase-only fonts we shouldn't check lowercase characters.
		if (chr == TEXTCOLOR_ESCAPE)
		{
			// We do not need to check for UTF-8 in here.
			if (*string == '[')
			{
				while (*string != '\0' && *string != ']')
				{
					++string;
				}
			}
			if (*string != '\0')
			{
				++string;
			}
			continue;
		}
		else if (chr != '\n')
		{
			int cc = GetCharCode(chr, true);
			if (chr != cc && myiswalpha(chr) && cc != getAlternative(chr))
			{
				return false;
			}
		}
	}

	return true;
}

//==========================================================================
//
// Find string width using this font
//
//==========================================================================

int FFont::StringWidth(const uint8_t *string, int spacing) const
{
	int w = 0;
	int maxw = 0;

	while (*string)
	{
		auto chr = GetCharFromString(string);
		if (chr == TEXTCOLOR_ESCAPE)
		{
			// We do not need to check for UTF-8 in here.
			if (*string == '[')
			{
				while (*string != '\0' && *string != ']')
				{
					++string;
				}
			}
			if (*string != '\0')
			{
				++string;
			}
			continue;
		}
		else if (chr == '\n')
		{
			if (w > maxw)
				maxw = w;
			w = 0;
		}
		else if (spacing >= 0)
		{
			w += GetCharWidth(chr) + GlobalKerning + spacing;
		}
		else
		{
			w -= spacing;
		}
	}

	return std::max(maxw, w);
}

//==========================================================================
//
// Get the largest ascender in the first line of this text.
//
//==========================================================================

int FFont::GetMaxAscender(const uint8_t* string) const
{
	int retval = 0;

	while (*string)
	{
		auto chr = GetCharFromString(string);
		if (chr == TEXTCOLOR_ESCAPE)
		{
			// We do not need to check for UTF-8 in here.
			if (*string == '[')
			{
				while (*string != '\0' && *string != ']')
				{
					++string;
				}
			}
			if (*string != '\0')
			{
				++string;
			}
			continue;
		}
		else if (chr == '\n')
		{
			break;
		}
		else
		{
			auto ctex = GetChar(chr, CR_UNTRANSLATED, nullptr);
			if (ctex)
			{
				auto offs = int(ctex->GetDisplayTopOffset());
				if (offs > retval) retval = offs;
			}
		}
	}

	return retval;
}

//==========================================================================
//
// FFont :: LoadTranslations
//
//==========================================================================

void FFont::LoadTranslations()
{
	unsigned int count = min<unsigned>(Chars.Size(), LastChar - FirstChar + 1);

	if (count == 0) return;
	int minlum = 255, maxlum = 0;
	for (unsigned int i = 0; i < count; i++)
	{
		if (Chars[i].OriginalPic)
		{
			auto pic = Chars[i].OriginalPic->GetTexture()->GetImage();
			RecordLuminosity(pic, &minlum, &maxlum);
		}
	}

	if (MinLum >= 0 && MinLum < minlum) minlum = MinLum;
	if (MaxLum > maxlum) maxlum = MaxLum;

	// Here we can set everything to a luminosity translation.
	Translations.Resize(NumTextColors);
	for (int i = 0; i < NumTextColors; i++)
	{
		if (i == CR_UNTRANSLATED) Translations[i] = 0;
 		else Translations[i] = LuminosityTranslation(i*2 + TranslationType, minlum, maxlum);
	}
}

//==========================================================================
//
// FFont :: FFont - default constructor
//
//==========================================================================

FFont::FFont (int lump, FName nm)
{
	FirstChar = LastChar = 0;
	Next = FirstFont;
	FirstFont = this;
	Lump = lump;
	FontName = nm;
	Cursor = '_';
	noTranslate = false;
}

//==========================================================================
//
// FFont :: FixXMoves
//
// If a font has gaps in its characters, set the missing characters'
// XMoves to either SpaceWidth or the unaccented or uppercase variant's
// XMove. Missing XMoves must be initialized with INT_MIN beforehand.
//
//==========================================================================

void FFont::FixXMoves()
{
	if (FirstChar < 'a' && LastChar >= 'z')
	{
		MixedCase = true;
		// First check if this is a mixed case font.
		// For this the basic Latin small characters all need to be present.
		for (int i = 'a'; i <= 'z'; i++)
			if (Chars[i - FirstChar].OriginalPic == nullptr)
			{
				MixedCase = false;
				break;
			}
	}

	for (int i = 0; i <= LastChar - FirstChar; ++i)
	{
		if (Chars[i].XMove == INT_MIN)
		{
			// Try an uppercase character.
			if (myislower(i + FirstChar))
			{
				int upper = upperforlower[FirstChar + i];
				if (upper >= FirstChar && upper <= LastChar )
				{
					Chars[i].XMove = Chars[upper - FirstChar].XMove;
					continue;
				}
			}
			// Try an unnaccented character.
			int noaccent = stripaccent(i + FirstChar);
			if (noaccent != i + FirstChar)
			{
				noaccent -= FirstChar;
				if (noaccent >= 0)
				{
					Chars[i].XMove = Chars[noaccent].XMove;
					continue;
				}
			}
			Chars[i].XMove = SpaceWidth;
		}
		if (Chars[i].OriginalPic)
		{
			int ofs = (int)Chars[i].OriginalPic->GetDisplayTopOffset();
			if (ofs > Displacement) Displacement = ofs;
		}
	}
}


void FFont::ClearOffsets()
{
	for (auto& c : Chars) if (c.OriginalPic) c.OriginalPic->SetOffsets(0, 0);
}