Fix: server menu tooltip shouldn't show language info (#12955)

[openttd-github.git] / src / townname.cpp

/*
 * This file is part of OpenTTD.
 * OpenTTD 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.
 * OpenTTD 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 OpenTTD. If not, see <http://www.gnu.org/licenses/>.
 */

/** @file townname.cpp %Town name generators. */

#include "stdafx.h"
#include "string_func.h"
#include "townname_type.h"
#include "town.h"
#include "strings_func.h"
#include "core/random_func.hpp"
#include "genworld.h"
#include "gfx_layout.h"
#include "strings_internal.h"

#include "table/townname.h"

#include "safeguards.h"


/**
 * Initializes this struct from town data
 * @param t town for which we will be printing name later
 */
TownNameParams::TownNameParams(const Town *t) :
                grfid(t->townnamegrfid), // by default, use supplied data
                type(t->townnametype)
{
        if (t->townnamegrfid != 0 && GetGRFTownName(t->townnamegrfid) == nullptr) {
                /* Fallback to english original */
                this->grfid = 0;
                this->type = SPECSTR_TOWNNAME_ENGLISH;
                return;
        }
}


/**
 * Fills builder with specified town name.
 * @param builder       The string builder.
 * @param par           Town name parameters.
 * @param townnameparts 'Encoded' town name.
 */
static void GetTownName(StringBuilder &builder, const TownNameParams *par, uint32_t townnameparts)
{
        if (par->grfid == 0) {
                auto tmp_params = MakeParameters(townnameparts);
                GetStringWithArgs(builder, par->type, tmp_params);
                return;
        }

        GRFTownNameGenerate(builder, par->grfid, par->type, townnameparts);
}

/**
 * Get the town name for the given parameters and parts.
 * @param par Town name parameters.
 * @param townnameparts 'Encoded' town name.
 * @return The town name.
 */
std::string GetTownName(const TownNameParams *par, uint32_t townnameparts)
{
        std::string result;
        StringBuilder builder(result);
        GetTownName(builder, par, townnameparts);
        return result;
}

/**
 * Fills builder with town's name.
 * @param builder String builder.
 * @param t       The town to get the name from.
 */
void GetTownName(StringBuilder &builder, const Town *t)
{
        TownNameParams par(t);
        GetTownName(builder, &par, t->townnameparts);
}

/**
 * Get the name of the given town.
 * @param t The town to get the name for.
 * @return The town name.
 */
std::string GetTownName(const Town *t)
{
        TownNameParams par(t);
        return GetTownName(&par, t->townnameparts);
}


/**
 * Verifies the town name is valid and unique.
 * @param r random bits
 * @param par town name parameters
 * @param town_names if a name is generated, check its uniqueness with the set
 * @return true iff name is valid and unique
 */
bool VerifyTownName(uint32_t r, const TownNameParams *par, TownNames *town_names)
{
        std::string name = GetTownName(par, r);

        /* Check size and width */
        if (Utf8StringLength(name) >= MAX_LENGTH_TOWN_NAME_CHARS) return false;

        if (town_names != nullptr) {
                if (town_names->find(name) != town_names->end()) return false;
                town_names->insert(name);
        } else {
                for (const Town *t : Town::Iterate()) {
                        /* We can't just compare the numbers since
                         * several numbers may map to a single name. */
                        if (t->name.empty()) {
                                if (name == GetTownName(t)) return false;
                        } else {
                                if (name == t->name) return false;
                        }
                }
        }

        return true;
}


/**
 * Generates valid town name.
 * @param randomizer the source of random data for generating the name
 * @param townnameparts if a name is generated, it's stored there
 * @param town_names if a name is generated, check its uniqueness with the set
 * @return true iff a name was generated
 */
bool GenerateTownName(Randomizer &randomizer, uint32_t *townnameparts, TownNames *town_names)
{
        TownNameParams par(_settings_game.game_creation.town_name);

        /* This function is called very often without entering the gameloop
         * in between. So reset layout cache to prevent it from growing too big. */
        Layouter::ReduceLineCache();

        /* Do not set i too low, since when we run out of names, we loop
         * for #tries only one time anyway - then we stop generating more
         * towns. Do not set it too high either, since looping through all
         * the other towns may take considerable amount of time (10000 is
         * too much). */
        for (int i = 1000; i != 0; i--) {
                uint32_t r = randomizer.Next();
                if (!VerifyTownName(r, &par, town_names)) continue;

                *townnameparts = r;
                return true;
        }

        return false;
}



/**
 * Generates a number from given seed.
 * @param shift_by number of bits seed is shifted to the right
 * @param max generated number is in interval 0...max-1
 * @param seed seed
 * @return seed transformed to a number from given range
 */
static inline uint32_t SeedChance(uint8_t shift_by, size_t max, uint32_t seed)
{
        return (GB(seed, shift_by, 16) * ClampTo<uint16_t>(max)) >> 16;
}


/**
 * Generates a number from given seed. Uses different algorithm than SeedChance().
 * @param shift_by number of bits seed is shifted to the right
 * @param max generated number is in interval 0...max-1
 * @param seed seed
 * @return seed transformed to a number from given range
 */
static inline uint32_t SeedModChance(uint8_t shift_by, size_t max, uint32_t seed)
{
        /* This actually gives *MUCH* more even distribution of the values
         * than SeedChance(), which is absolutely horrible in that. If
         * you do not believe me, try with i.e. the Czech town names,
         * compare the words (nicely visible on prefixes) generated by
         * SeedChance() and SeedModChance(). Do not get discouraged by the
         * never-use-modulo myths, which hold true only for the linear
         * congruential generators (and Random() isn't such a generator).
         * --pasky
         * TODO: Perhaps we should use it for all the name generators? --pasky */
        return (seed >> shift_by) % max;
}


/**
 * Generates a number from given seed.
 * @param shift_by number of bits seed is shifted to the right
 * @param max generated number is in interval -bias...max-1
 * @param seed seed
 * @param bias minimum value that can be returned
 * @return seed transformed to a number from given range
 */
static inline int32_t SeedChanceBias(uint8_t shift_by, size_t max, uint32_t seed, int bias)
{
        return SeedChance(shift_by, max + bias, seed) - bias;
}


/**
 * Replaces a string beginning in 'org' with 'rep'.
 * @param org     string to replace, has to be 4 characters long
 * @param rep     string to be replaced with, has to be 4 characters long
 * @param builder string builder of the town name
 * @param start   the start index within the builder for the town name
 */
static void ReplaceWords(const char *org, const char *rep, StringBuilder &builder, size_t start)
{
        assert(strlen(org) == 4 && strlen(rep) == 4 && builder.CurrentIndex() - start >= 4);
        if (strncmp(&builder[start], org, 4) == 0) memcpy(&builder[start], rep, 4); // Safe as the string in buf is always more than 4 characters long.
}


/**
 * Replaces english curses and ugly letter combinations by nicer ones.
 * @param builder  The builder with the town name
 * @param start    The start index into the builder for the first town name
 * @param original English (Original) generator was used
 */
static void ReplaceEnglishWords(StringBuilder &builder, size_t start, bool original)
{
        ReplaceWords("Cunt", "East", builder, start);
        ReplaceWords("Slag", "Pits", builder, start);
        ReplaceWords("Slut", "Edin", builder, start);
        if (!original) ReplaceWords("Fart", "Boot", builder, start); // never happens with 'English (Original)'
        ReplaceWords("Drar", "Quar", builder, start);
        ReplaceWords("Dreh", "Bash", builder, start);
        ReplaceWords("Frar", "Shor", builder, start);
        ReplaceWords("Grar", "Aber", builder, start);
        ReplaceWords("Brar", "Over", builder, start);
        ReplaceWords("Wrar", original ? "Inve" : "Stan", builder, start);
}

/**
 * Generates English (Original) town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeEnglishOriginalTownName(StringBuilder &builder, uint32_t seed)
{
        size_t start = builder.CurrentIndex();

        /* optional first segment */
        int i = SeedChanceBias(0, std::size(_name_original_english_1), seed, 50);
        if (i >= 0) builder += _name_original_english_1[i];

        /* mandatory middle segments */
        builder += _name_original_english_2[SeedChance(4,  std::size(_name_original_english_2), seed)];
        builder += _name_original_english_3[SeedChance(7,  std::size(_name_original_english_3), seed)];
        builder += _name_original_english_4[SeedChance(10, std::size(_name_original_english_4), seed)];
        builder += _name_original_english_5[SeedChance(13, std::size(_name_original_english_5), seed)];

        /* optional last segment */
        i = SeedChanceBias(15, std::size(_name_original_english_6), seed, 60);
        if (i >= 0) builder += _name_original_english_6[i];

        /* Ce, Ci => Ke, Ki */
        if (builder[start] == 'C' && (builder[start + 1] == 'e' || builder[start + 1] == 'i')) {
                builder[start] = 'K';
        }

        assert(builder.CurrentIndex() - start >= 4);
        ReplaceEnglishWords(builder, start, true);
}


/**
 * Generates English (Additional) town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeEnglishAdditionalTownName(StringBuilder &builder, uint32_t seed)
{
        size_t start = builder.CurrentIndex();

        /* optional first segment */
        int i = SeedChanceBias(0, std::size(_name_additional_english_prefix), seed, 50);
        if (i >= 0) builder += _name_additional_english_prefix[i];

        if (SeedChance(3, 20, seed) >= 14) {
                builder += _name_additional_english_1a[SeedChance(6, std::size(_name_additional_english_1a), seed)];
        } else {
                builder += _name_additional_english_1b1[SeedChance(6, std::size(_name_additional_english_1b1), seed)];
                builder += _name_additional_english_1b2[SeedChance(9, std::size(_name_additional_english_1b2), seed)];
                if (SeedChance(11, 20, seed) >= 4) {
                        builder += _name_additional_english_1b3a[SeedChance(12, std::size(_name_additional_english_1b3a), seed)];
                } else {
                        builder += _name_additional_english_1b3b[SeedChance(12, std::size(_name_additional_english_1b3b), seed)];
                }
        }

        builder += _name_additional_english_2[SeedChance(14, std::size(_name_additional_english_2), seed)];

        /* optional last segment */
        i = SeedChanceBias(15, std::size(_name_additional_english_3), seed, 60);
        if (i >= 0) builder += _name_additional_english_3[i];

        assert(builder.CurrentIndex() - start >= 4);
        ReplaceEnglishWords(builder, start, false);
}


/**
 * Generates Austrian town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeAustrianTownName(StringBuilder &builder, uint32_t seed)
{
        /* Bad, Maria, Gross, ... */
        int i = SeedChanceBias(0, std::size(_name_austrian_a1), seed, 15);
        if (i >= 0) builder += _name_austrian_a1[i];

        int j = 0;

        i = SeedChance(4, 6, seed);
        if (i >= 4) {
                /* Kaisers-kirchen */
                builder += _name_austrian_a2[SeedChance( 7, std::size(_name_austrian_a2), seed)];
                builder += _name_austrian_a3[SeedChance(13, std::size(_name_austrian_a3), seed)];
        } else if (i >= 2) {
                /* St. Johann */
                builder += _name_austrian_a5[SeedChance( 7, std::size(_name_austrian_a5), seed)];
                builder += _name_austrian_a6[SeedChance( 9, std::size(_name_austrian_a6), seed)];
                j = 1; // More likely to have a " an der " or " am "
        } else {
                /* Zell */
                builder += _name_austrian_a4[SeedChance( 7, std::size(_name_austrian_a4), seed)];
        }

        i = SeedChance(1, 6, seed);
        if (i >= 4 - j) {
                /* an der Donau (rivers) */
                builder += _name_austrian_f1[SeedChance(4, std::size(_name_austrian_f1), seed)];
                builder += _name_austrian_f2[SeedChance(5, std::size(_name_austrian_f2), seed)];
        } else if (i >= 2 - j) {
                /* am Dachstein (mountains) */
                builder += _name_austrian_b1[SeedChance(4, std::size(_name_austrian_b1), seed)];
                builder += _name_austrian_b2[SeedChance(5, std::size(_name_austrian_b2), seed)];
        }
}


/**
 * Generates German town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeGermanTownName(StringBuilder &builder, uint32_t seed)
{
        uint seed_derivative = SeedChance(7, 28, seed);

        /* optional prefix */
        if (seed_derivative == 12 || seed_derivative == 19) {
                uint i = SeedChance(2, std::size(_name_german_pre), seed);
                builder += _name_german_pre[i];
        }

        /* mandatory middle segments including option of hardcoded name */
        uint i = SeedChance(3, std::size(_name_german_real) + std::size(_name_german_1), seed);
        if (i < std::size(_name_german_real)) {
                builder += _name_german_real[i];
        } else {
                builder += _name_german_1[i - std::size(_name_german_real)];

                i = SeedChance(5, std::size(_name_german_2), seed);
                builder += _name_german_2[i];
        }

        /* optional suffix */
        if (seed_derivative == 24) {
                i = SeedChance(9, std::size(_name_german_4_an_der) + std::size(_name_german_4_am), seed);
                if (i < std::size(_name_german_4_an_der)) {
                        builder += _name_german_3_an_der[0];
                        builder += _name_german_4_an_der[i];
                } else {
                        builder += _name_german_3_am[0];
                        builder += _name_german_4_am[i - std::size(_name_german_4_an_der)];
                }
        }
}


/**
 * Generates Latin-American town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeSpanishTownName(StringBuilder &builder, uint32_t seed)
{
        builder += _name_spanish_real[SeedChance(0, std::size(_name_spanish_real), seed)];
}


/**
 * Generates French town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeFrenchTownName(StringBuilder &builder, uint32_t seed)
{
        builder += _name_french_real[SeedChance(0, std::size(_name_french_real), seed)];
}


/**
 * Generates Silly town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeSillyTownName(StringBuilder &builder, uint32_t seed)
{
        builder += _name_silly_1[SeedChance( 0, std::size(_name_silly_1), seed)];
        builder += _name_silly_2[SeedChance(16, std::size(_name_silly_2), seed)];
}


/**
 * Generates Swedish town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeSwedishTownName(StringBuilder &builder, uint32_t seed)
{
        /* optional first segment */
        int i = SeedChanceBias(0, std::size(_name_swedish_1), seed, 50);
        if (i >= 0) builder += _name_swedish_1[i];

        /* mandatory middle segments including option of hardcoded name */
        if (SeedChance(4, 5, seed) >= 3) {
                builder += _name_swedish_2[SeedChance( 7, std::size(_name_swedish_2), seed)];
        } else {
                builder += _name_swedish_2a[SeedChance( 7, std::size(_name_swedish_2a), seed)];
                builder += _name_swedish_2b[SeedChance(10, std::size(_name_swedish_2b), seed)];
                builder += _name_swedish_2c[SeedChance(13, std::size(_name_swedish_2c), seed)];
        }

        builder += _name_swedish_3[SeedChance(16, std::size(_name_swedish_3), seed)];
}


/**
 * Generates Dutch town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeDutchTownName(StringBuilder &builder, uint32_t seed)
{
        /* optional first segment */
        int i = SeedChanceBias(0, std::size(_name_dutch_1), seed, 50);
        if (i >= 0) builder += _name_dutch_1[i];

        /* mandatory middle segments including option of hardcoded name */
        if (SeedChance(6, 9, seed) > 4) {
                builder += _name_dutch_2[SeedChance( 9, std::size(_name_dutch_2), seed)];
        } else {
                builder += _name_dutch_3[SeedChance( 9, std::size(_name_dutch_3), seed)];
                builder += _name_dutch_4[SeedChance(12, std::size(_name_dutch_4), seed)];
        }

        builder += _name_dutch_5[SeedChance(15, std::size(_name_dutch_5), seed)];
}


/**
 * Generates Finnish town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeFinnishTownName(StringBuilder &builder, uint32_t seed)
{
        size_t start = builder.CurrentIndex();

        /* Select randomly if town name should consists of one or two parts. */
        if (SeedChance(0, 15, seed) >= 10) {
                builder += _name_finnish_real[SeedChance(2, std::size(_name_finnish_real), seed)];
                return;
        }

        if (SeedChance(0, 15, seed) >= 5) {
                /* A two-part name by combining one of _name_finnish_1 + "la"/"lä"
                 * The reason for not having the contents of _name_finnish_{1,2} in the same table is
                 * that the ones in _name_finnish_2 are not good for this purpose. */
                uint sel = SeedChance( 0, std::size(_name_finnish_1), seed);
                builder += _name_finnish_1[sel];
                size_t last = builder.CurrentIndex() - 1;
                if (builder[last] == 'i') builder[last] = 'e';

                std::string_view view(&builder[start], builder.CurrentIndex() - start);
                if (view.find_first_of("aouAOU") != std::string_view::npos) {
                        builder += "la";
                } else {
                        builder += "l\u00e4";
                }
                return;
        }

        /* A two-part name by combining one of _name_finnish_{1,2} + _name_finnish_3.
         * Why aren't _name_finnish_{1,2} just one table? See above. */
        uint sel = SeedChance(2, std::size(_name_finnish_1) + std::size(_name_finnish_2), seed);
        if (sel >= std::size(_name_finnish_1)) {
                builder += _name_finnish_2[sel - std::size(_name_finnish_1)];
        } else {
                builder += _name_finnish_1[sel];
        }

        builder += _name_finnish_3[SeedChance(10, std::size(_name_finnish_3), seed)];
}


/**
 * Generates Polish town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakePolishTownName(StringBuilder &builder, uint32_t seed)
{
        /* optional first segment */
        uint i = SeedChance(0,
                        std::size(_name_polish_2_o) + std::size(_name_polish_2_m) +
                        std::size(_name_polish_2_f) + std::size(_name_polish_2_n),
                        seed);
        uint j = SeedChance(2, 20, seed);


        if (i < std::size(_name_polish_2_o)) {
                builder += _name_polish_2_o[SeedChance(3, std::size(_name_polish_2_o), seed)];
                return;
        }

        if (i < std::size(_name_polish_2_m) + std::size(_name_polish_2_o)) {
                if (j < 4) {
                        builder += _name_polish_1_m[SeedChance(5, std::size(_name_polish_1_m), seed)];
                }

                builder += _name_polish_2_m[SeedChance(7, std::size(_name_polish_2_m), seed)];

                if (j >= 4 && j < 16) {
                        builder += _name_polish_3_m[SeedChance(10, std::size(_name_polish_3_m), seed)];
                }

                return;
        }

        if (i < std::size(_name_polish_2_f) + std::size(_name_polish_2_m) + std::size(_name_polish_2_o)) {
                if (j < 4) {
                        builder += _name_polish_1_f[SeedChance(5, std::size(_name_polish_1_f), seed)];
                }

                builder += _name_polish_2_f[SeedChance(7, std::size(_name_polish_2_f), seed)];

                if (j >= 4 && j < 16) {
                        builder += _name_polish_3_f[SeedChance(10, std::size(_name_polish_3_f), seed)];
                }

                return;
        }

        if (j < 4) {
                builder += _name_polish_1_n[SeedChance(5, std::size(_name_polish_1_n), seed)];
        }

        builder += _name_polish_2_n[SeedChance(7, std::size(_name_polish_2_n), seed)];

        if (j >= 4 && j < 16) {
                builder += _name_polish_3_n[SeedChance(10, std::size(_name_polish_3_n), seed)];
        }

        return;
}


/**
 * Generates Czech town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeCzechTownName(StringBuilder &builder, uint32_t seed)
{
        /* 1:3 chance to use a real name. */
        if (SeedModChance(0, 4, seed) == 0) {
                builder += _name_czech_real[SeedModChance(4, std::size(_name_czech_real), seed)];
                return;
        }

        /* Probability of prefixes/suffixes
         * 0..11 prefix, 12..13 prefix+suffix, 14..17 suffix, 18..31 nothing */
        int prob_tails = SeedModChance(2, 32, seed);
        bool do_prefix = prob_tails < 12;
        bool do_suffix = prob_tails > 11 && prob_tails < 17;
        bool dynamic_subst;

        /* IDs of the respective parts */
        int prefix = 0, ending = 0, suffix = 0;
        size_t postfix = 0;
        size_t stem;

        /* The select criteria. */
        CzechGender gender;
        CzechChoose choose;
        CzechAllow allow;

        if (do_prefix) prefix = SeedModChance(5, std::size(_name_czech_adj) * 12, seed) / 12;
        if (do_suffix) suffix = SeedModChance(7, std::size(_name_czech_suffix), seed);
        /* 3:1 chance 3:1 to use dynamic substantive */
        stem = SeedModChance(9,
                        std::size(_name_czech_subst_full) + 3 * std::size(_name_czech_subst_stem),
                        seed);
        if (stem < std::size(_name_czech_subst_full)) {
                /* That was easy! */
                dynamic_subst = false;
                gender = _name_czech_subst_full[stem].gender;
                choose = _name_czech_subst_full[stem].choose;
                allow = _name_czech_subst_full[stem].allow;
        } else {
                uint map[std::size(_name_czech_subst_ending)];
                int ending_start = -1, ending_stop = -1;

                /* Load the substantive */
                dynamic_subst = true;
                stem -= std::size(_name_czech_subst_full);
                stem %= std::size(_name_czech_subst_stem);
                gender = _name_czech_subst_stem[stem].gender;
                choose = _name_czech_subst_stem[stem].choose;
                allow = _name_czech_subst_stem[stem].allow;

                /* Load the postfix (1:1 chance that a postfix will be inserted) */
                postfix = SeedModChance(14, std::size(_name_czech_subst_postfix) * 2, seed);

                if (choose & CZC_POSTFIX) {
                        /* Always get a real postfix. */
                        postfix %= std::size(_name_czech_subst_postfix);
                }
                if (choose & CZC_NOPOSTFIX) {
                        /* Always drop a postfix. */
                        postfix += std::size(_name_czech_subst_postfix);
                }
                if (postfix < std::size(_name_czech_subst_postfix)) {
                        choose |= CZC_POSTFIX;
                } else {
                        choose |= CZC_NOPOSTFIX;
                }

                /* Localize the array segment containing a good gender */
                for (ending = 0; ending < (int)std::size(_name_czech_subst_ending); ending++) {
                        const CzechNameSubst *e = &_name_czech_subst_ending[ending];

                        if (gender == CZG_FREE ||
                                        (gender == CZG_NFREE && e->gender != CZG_SNEUT && e->gender != CZG_PNEUT) ||
                                         gender == e->gender) {
                                if (ending_start < 0) {
                                        ending_start = ending;
                                }
                        } else if (ending_start >= 0) {
                                ending_stop = ending - 1;
                                break;
                        }
                }
                if (ending_stop < 0) {
                        /* Whoa. All the endings matched. */
                        ending_stop = ending - 1;
                }

                /* Make a sequential map of the items with good mask */
                size_t i = 0;
                for (ending = ending_start; ending <= ending_stop; ending++) {
                        const CzechNameSubst *e = &_name_czech_subst_ending[ending];

                        if ((e->choose & choose) == choose && (e->allow & allow) != 0) {
                                map[i++] = ending;
                        }
                }
                assert(i > 0);

                /* Load the ending */
                ending = map[SeedModChance(16, (int)i, seed)];
                /* Override possible CZG_*FREE; this must be a real gender,
                 * otherwise we get overflow when modifying the adjectivum. */
                gender = _name_czech_subst_ending[ending].gender;
                assert(gender != CZG_FREE && gender != CZG_NFREE);
        }

        if (do_prefix && (_name_czech_adj[prefix].choose & choose) != choose) {
                /* Throw away non-matching prefix. */
                do_prefix = false;
        }

        /* Now finally construct the name */
        if (do_prefix) {
                CzechPattern pattern = _name_czech_adj[prefix].pattern;

                builder += _name_czech_adj[prefix].name;

                size_t endpos = builder.CurrentIndex() - 1;
                /* Find the first character in a UTF-8 sequence */
                while (GB(builder[endpos], 6, 2) == 2) endpos--;
                builder.RemoveElementsFromBack(builder.CurrentIndex() - endpos);

                if (gender == CZG_SMASC && pattern == CZP_PRIVL) {
                        /* -ovX -> -uv */
                        builder[endpos - 2] = 'u';
                } else {
                        builder += _name_czech_patmod[gender][pattern];
                }

                builder += ' ';
        }

        if (dynamic_subst) {
                builder += _name_czech_subst_stem[stem].name;
                if (postfix < std::size(_name_czech_subst_postfix)) {
                        const char *poststr = _name_czech_subst_postfix[postfix];
                        const char *endstr = _name_czech_subst_ending[ending].name;

                        size_t postlen = strlen(poststr);
                        size_t endlen = strlen(endstr);
                        assert(postlen > 0 && endlen > 0);

                        /* Kill the "avava" and "Jananna"-like cases */
                        if (postlen < 2 || postlen > endlen ||
                                        ((poststr[1] != 'v' || poststr[1] != endstr[1]) &&
                                        poststr[2] != endstr[1])) {
                                builder += poststr;

                                /* k-i -> c-i, h-i -> z-i */
                                if (endstr[0] == 'i') {
                                        size_t last = builder.CurrentIndex() - 1;
                                        switch (builder[last]) {
                                                case 'k': builder[last] = 'c'; break;
                                                case 'h': builder[last] = 'z'; break;
                                                default: break;
                                        }
                                }
                        }
                }
                builder += _name_czech_subst_ending[ending].name;
        } else {
                builder += _name_czech_subst_full[stem].name;
        }

        if (do_suffix) {
                builder += " ";
                builder += _name_czech_suffix[suffix];
        }
}


/**
 * Generates Romanian town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeRomanianTownName(StringBuilder &builder, uint32_t seed)
{
        builder += _name_romanian_real[SeedChance(0, std::size(_name_romanian_real), seed)];
}


/**
 * Generates Slovak town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeSlovakTownName(StringBuilder &builder, uint32_t seed)
{
        builder += _name_slovak_real[SeedChance(0, std::size(_name_slovak_real), seed)];
}


/**
 * Generates Norwegian town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeNorwegianTownName(StringBuilder &builder, uint32_t seed)
{
        /* Use first 4 bit from seed to decide whether or not this town should
         * have a real name 3/16 chance.  Bit 0-3 */
        if (SeedChance(0, 15, seed) < 3) {
                /* Use 7bit for the realname table index.  Bit 4-10 */
                builder += _name_norwegian_real[SeedChance(4, std::size(_name_norwegian_real), seed)];
                return;
        }

        /* Use 7bit for the first fake part.  Bit 4-10 */
        builder += _name_norwegian_1[SeedChance(4, std::size(_name_norwegian_1), seed)];
        /* Use 7bit for the last fake part.  Bit 11-17 */
        builder += _name_norwegian_2[SeedChance(11, std::size(_name_norwegian_2), seed)];
}


/**
 * Generates Hungarian town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeHungarianTownName(StringBuilder &builder, uint32_t seed)
{
        if (SeedChance(12, 15, seed) < 3) {
                builder += _name_hungarian_real[SeedChance(0, std::size(_name_hungarian_real), seed)];
                return;
        }

        /* optional first segment */
        uint i = SeedChance(3, std::size(_name_hungarian_1) * 3, seed);
        if (i < std::size(_name_hungarian_1)) builder += _name_hungarian_1[i];

        /* mandatory middle segments */
        builder += _name_hungarian_2[SeedChance(3, std::size(_name_hungarian_2), seed)];
        builder += _name_hungarian_3[SeedChance(6, std::size(_name_hungarian_3), seed)];

        /* optional last segment */
        i = SeedChance(10, std::size(_name_hungarian_4) * 3, seed);
        if (i < std::size(_name_hungarian_4)) {
                builder += _name_hungarian_4[i];
        }
}


/**
 * Generates Swiss town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeSwissTownName(StringBuilder &builder, uint32_t seed)
{
        builder += _name_swiss_real[SeedChance(0, std::size(_name_swiss_real), seed)];
}


/**
 * Generates Danish town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeDanishTownName(StringBuilder &builder, uint32_t seed)
{
        /* optional first segment */
        int i = SeedChanceBias(0, std::size(_name_danish_1), seed, 50);
        if (i >= 0) builder += _name_danish_1[i];

        /* middle segments removed as this algorithm seems to create much more realistic names */
        builder += _name_danish_2[SeedChance( 7, std::size(_name_danish_2), seed)];
        builder += _name_danish_3[SeedChance(16, std::size(_name_danish_3), seed)];
}


/**
 * Generates Turkish town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeTurkishTownName(StringBuilder &builder, uint32_t seed)
{
        uint i = SeedModChance(0, 5, seed);

        switch (i) {
                case 0:
                        builder += _name_turkish_prefix[SeedModChance( 2, std::size(_name_turkish_prefix), seed)];

                        /* middle segment */
                        builder += _name_turkish_middle[SeedModChance( 4, std::size(_name_turkish_middle), seed)];

                        /* optional suffix */
                        if (SeedModChance(0, 7, seed) == 0) {
                                builder += _name_turkish_suffix[SeedModChance( 10, std::size(_name_turkish_suffix), seed)];
                        }
                        break;

                case 1: case 2:
                        builder += _name_turkish_prefix[SeedModChance( 2, std::size(_name_turkish_prefix), seed)];
                        builder += _name_turkish_suffix[SeedModChance( 4, std::size(_name_turkish_suffix), seed)];
                        break;

                default:
                        builder += _name_turkish_real[SeedModChance( 4, std::size(_name_turkish_real), seed)];
                        break;
        }
}


/**
 * Generates Italian town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeItalianTownName(StringBuilder &builder, uint32_t seed)
{
        if (SeedModChance(0, 6, seed) == 0) { // real city names
                builder += _name_italian_real[SeedModChance(4, std::size(_name_italian_real), seed)];
                return;
        }

        static const char * const mascul_femin_italian[] = {
                "o",
                "a",
        };

        if (SeedModChance(0, 8, seed) == 0) { // prefix
                builder += _name_italian_pref[SeedModChance(11, std::size(_name_italian_pref), seed)];
        }

        uint i = SeedChance(0, 2, seed);
        if (i == 0) { // masculine form
                builder += _name_italian_1m[SeedModChance(4, std::size(_name_italian_1m), seed)];
        } else { // feminine form
                builder += _name_italian_1f[SeedModChance(4, std::size(_name_italian_1f), seed)];
        }

        if (SeedModChance(3, 3, seed) == 0) {
                builder += _name_italian_2[SeedModChance(11, std::size(_name_italian_2), seed)];
                builder += mascul_femin_italian[i];
        } else {
                builder += _name_italian_2i[SeedModChance(16, std::size(_name_italian_2i), seed)];
        }

        if (SeedModChance(15, 4, seed) == 0) {
                if (SeedModChance(5, 2, seed) == 0) { // generic suffix
                        builder += _name_italian_3[SeedModChance(4, std::size(_name_italian_3), seed)];
                } else { // river name suffix
                        builder += _name_italian_river1[SeedModChance(4, std::size(_name_italian_river1), seed)];
                        builder += _name_italian_river2[SeedModChance(16, std::size(_name_italian_river2), seed)];
                }
        }
}


/**
 * Generates Catalan town name from given seed.
 * @param builder string builder
 * @param seed town name seed
 */
static void MakeCatalanTownName(StringBuilder &builder, uint32_t seed)
{
        if (SeedModChance(0, 3, seed) == 0) { // real city names
                builder += _name_catalan_real[SeedModChance(4, std::size(_name_catalan_real), seed)];
                return;
        }

        if (SeedModChance(0, 2, seed) == 0) { // prefix
                builder += _name_catalan_pref[SeedModChance(11, std::size(_name_catalan_pref), seed)];
        }

        uint i = SeedChance(0, 2, seed);
        if (i == 0) { // masculine form
                builder += _name_catalan_1m[SeedModChance(4, std::size(_name_catalan_1m), seed)];
                builder += _name_catalan_2m[SeedModChance(11, std::size(_name_catalan_2m), seed)];
        } else { // feminine form
                builder += _name_catalan_1f[SeedModChance(4, std::size(_name_catalan_1f), seed)];
                builder += _name_catalan_2f[SeedModChance(11, std::size(_name_catalan_2f), seed)];
        }

        if (SeedModChance(15, 5, seed) == 0) {
                if (SeedModChance(5, 2, seed) == 0) { // generic suffix
                        builder += _name_catalan_3[SeedModChance(4, std::size(_name_catalan_3), seed)];
                } else { // river name suffix
                        builder += _name_catalan_river1[SeedModChance(4, std::size(_name_catalan_river1), seed)];
                }
        }
}


/**
 * Type for all town name generator functions.
 * @param builder The builder to write the name to.
 * @param seed The seed of the town name.
 */
typedef void TownNameGenerator(StringBuilder &builder, uint32_t seed);

/** Town name generators */
static TownNameGenerator *_town_name_generators[] = {
        MakeEnglishOriginalTownName,  // replaces first 4 characters of name
        MakeFrenchTownName,
        MakeGermanTownName,
        MakeEnglishAdditionalTownName, // replaces first 4 characters of name
        MakeSpanishTownName,
        MakeSillyTownName,
        MakeSwedishTownName,
        MakeDutchTownName,
        MakeFinnishTownName, // _name_finnish_1
        MakePolishTownName,
        MakeSlovakTownName,
        MakeNorwegianTownName,
        MakeHungarianTownName,
        MakeAustrianTownName,
        MakeRomanianTownName,
        MakeCzechTownName, // _name_czech_adj + _name_czech_patmod + 1 + _name_czech_subst_stem + _name_czech_subst_postfix
        MakeSwissTownName,
        MakeDanishTownName,
        MakeTurkishTownName,
        MakeItalianTownName,
        MakeCatalanTownName,
};


/**
 * Generates town name from given seed.
 * @param builder string builder to write to
 * @param lang    town name language
 * @param seed    generation seed
 */
void GenerateTownNameString(StringBuilder &builder, size_t lang, uint32_t seed)
{
        assert(lang < std::size(_town_name_generators));
        return _town_name_generators[lang](builder, seed);
}