/*

mathnodes.w

Copyright 2006-2010 Taco Hoekwater <taco@@luatex.org>

This file is part of LuaTeX.

LuaTeX is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2 of the License, or (at your
option) any later version.

LuaTeX 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 Lesser General Public
License for more details.

You should have received a copy of the GNU General Public License along
with LuaTeX; if not, see <http://www.gnu.org/licenses/>.

*/

#include "ptexlib.h"

/*tex

We support the traditional math codes as well as larger ones suitable for
\UNICODE\ input and fonts.

*/

static sa_tree mathcode_head = NULL;

/*tex the |0xFFFFFFFF| is a flag value. */

#define MATHCODESTACK 8
#define MATHCODEDEFAULT 0xFFFFFFFF
#define MATHCODEACTIVE  0xFFFFFFFE

/*tex

Delcodes are also went larger.

*/

static sa_tree delcode_head = NULL;

#define DELCODESTACK 4
#define DELCODEDEFAULT 0xFFFFFFFF

/*tex

We now get lots of helpers for definitions and printing. The storage model
that we use is different because we can have many more so we need to be
sparse. Therefore we use trees.

*/


#define print_hex_digit(A) do { \
    if ((A)>=10) print_char('A'+(A)-10); \
    else print_char('0'+(A)); \
  } while (0)

#define two_hex(A) do { \
    print_hex_digit((A)/16); \
    print_hex_digit((A)%16); \
  } while (0)

#define four_hex(A) do { \
    two_hex((A)/256); \
    two_hex((A)%256); \
  } while (0)

#define six_hex(A) do { \
    two_hex((A)/65536); \
    two_hex(((A)%65536)/256); \
    two_hex((A)%256); \
  } while (0)

mathcodeval mathchar_from_integer(int value, int extcode)
{
    mathcodeval mval;
    if (extcode == tex_mathcode) {
        mval.class_value = (value / 0x1000);
        mval.family_value = ((value % 0x1000) / 0x100);
        mval.character_value = (value % 0x100);
    } else {
        int mfam = (value / 0x200000) & 0x7FF;
        mval.class_value = mfam % 0x08;
        mval.family_value = mfam / 0x08;
        mval.character_value = value & 0x1FFFFF;
    }
    return mval;
}

void show_mathcode_value_old(int value)
{
    print_char('"');
    four_hex(value);
}

void show_mathcode_value(mathcodeval c)
{
    print_char('"');
    print_hex_digit(c.class_value);
    print_char('"');
    two_hex(c.family_value);
    print_char('"');
    six_hex(c.character_value);
}

static void show_mathcode(int n)
{
    mathcodeval c = get_math_code(n);
    tprint_esc("Umathcode");
    print_int(n);
    print_char('=');
    show_mathcode_value(c);
}

static void unsavemathcode(quarterword gl)
{
    sa_stack_item st;
    if (mathcode_head->stack == NULL)
        return;
    while (mathcode_head->stack_ptr > 0 && abs(mathcode_head->stack[mathcode_head->stack_ptr].level) >= gl) {
        st = mathcode_head->stack[mathcode_head->stack_ptr];
        if (st.level > 0) {
            rawset_sa_item(mathcode_head, st.code, st.value);
            if (tracing_restores_par > 1) {
                begin_diagnostic();
                print_char('{');
                tprint("restoring");
                print_char(' ');
                show_mathcode(st.code);
                print_char('}');
                end_diagnostic(false);
            }
        }
        (mathcode_head->stack_ptr)--;
    }
}

void set_math_code(int n, int mathclass, int mathfamily, int mathcharacter, quarterword level)
{
    sa_tree_item v;
    if (mathclass == 8 && mathfamily == 0 && mathcharacter == 0) {
        v.uint_value = MATHCODEACTIVE;
    } else {
        v.math_code_value.class_value = mathclass;
        v.math_code_value.family_value = mathfamily;
        v.math_code_value.character_value = mathcharacter;
    }
    set_sa_item(mathcode_head, n, v, level);
    if (tracing_assigns_par > 1) {
        begin_diagnostic();
        print_char('{');
        tprint("assigning");
        print_char(' ');
        show_mathcode(n);
        print_char('}');
        end_diagnostic(false);
    }
}

mathcodeval get_math_code(int n)
{
    mathcodeval d;
    sa_tree_item v = get_sa_item(mathcode_head, n);
    if (v.uint_value == MATHCODEDEFAULT) {
        d.class_value = 0;
        d.family_value = 0;
        d.character_value = n;
    } else if (v.uint_value == MATHCODEACTIVE) {
        d.class_value = 8;
        d.family_value = 0;
        d.character_value = 0;
    } else {
        d.class_value = v.math_code_value.class_value;
        if (d.class_value == 8) {
            d.family_value = 0;
            d.character_value = n;
        } else {
            d.family_value = v.math_code_value.family_value;
            d.character_value = v.math_code_value.character_value;
        }
    }
    return d;
}

int get_math_code_num(int n)
{
    mathcodeval d = get_math_code(n);
    return (d.class_value + (d.family_value * 8)) * (65536 * 32) + d.character_value;
}

static void initializemathcode(void)
{
    sa_tree_item sa_value = { 0 };
    sa_value.uint_value = MATHCODEDEFAULT;
    mathcode_head = new_sa_tree(MATHCODESTACK, 1, sa_value);
}

static void dumpmathcode(void)
{
    dump_sa_tree(mathcode_head,"mathcodes");
}

static void undumpmathcode(void)
{
    mathcode_head = undump_sa_tree("mathcodes");
}

static void show_delcode(int n)
{
    delcodeval c;
    c = get_del_code(n);
    tprint_esc("Udelcode");
    print_int(n);
    print_char('=');
    if (c.small_family_value < 0) {
        print_char('-');
        print_char('1');
    } else {
        print_char('"');
        two_hex(c.small_family_value);
        six_hex(c.small_character_value);
    }
}

static void unsavedelcode(quarterword gl)
{
    sa_stack_item st;
    if (delcode_head->stack == NULL)
        return;
    while (delcode_head->stack_ptr > 0 && abs(delcode_head->stack[delcode_head->stack_ptr].level) >= gl) {
        st = delcode_head->stack[delcode_head->stack_ptr];
        if (st.level > 0) {
            rawset_sa_item(delcode_head, st.code, st.value);
            if (tracing_restores_par > 1) {
                begin_diagnostic();
                print_char('{');
                tprint("restoring");
                print_char(' ');
                show_delcode(st.code);
                print_char('}');
                end_diagnostic(false);
            }
        }
        (delcode_head->stack_ptr)--;
    }
}

void set_del_code(int n, int smathfamily, int smathcharacter, int lmathfamily, int lmathcharacter, quarterword gl)
{
    sa_tree_item v;
    v.del_code_value.class_value = 0;
    v.del_code_value.small_family_value = smathfamily;
    v.del_code_value.small_character_value = smathcharacter;
    v.del_code_value.dummy_value = 0;
    v.del_code_value.large_family_value = lmathfamily;
    v.del_code_value.large_character_value = lmathcharacter;
    /*tex Always global! */
    set_sa_item(delcode_head, n, v, gl);
    if (tracing_assigns_par > 1) {
        begin_diagnostic();
        print_char('{');
        tprint("assigning");
        print_char(' ');
        show_delcode(n);
        print_char('}');
        end_diagnostic(false);
    }
}

delcodeval get_del_code(int n)
{
    delcodeval d;
    sa_tree_item v = get_sa_item(delcode_head, n);
    if (v.uint_value == DELCODEDEFAULT) {
        d.class_value = 0;
        d.small_family_value = -1;
        d.small_character_value = 0;
        d.large_family_value = 0;
        d.large_character_value = 0;
    } else {
        d.class_value = v.del_code_value.class_value;
        d.small_family_value = v.del_code_value.small_family_value;
        d.small_character_value = v.del_code_value.small_character_value;
        d.large_family_value = v.del_code_value.large_family_value;
        d.large_character_value = v.del_code_value.large_character_value;
    }
    return d;
}

/*tex

This really only works for old-style delcodes!

*/

int get_del_code_num(int n)
{
    delcodeval d = get_del_code(n);
    if (d.small_family_value < 0) {
        return -1;
    } else {
        return ((d.small_family_value * 256  + d.small_character_value) * 4096 +
                (d.large_family_value * 256) + d.large_character_value);
    }
}

static void initializedelcode(void)
{
    sa_tree_item sa_value = { 0 };
    sa_value.uint_value = DELCODEDEFAULT;
    delcode_head = new_sa_tree(DELCODESTACK, 2, sa_value);
}

static void dumpdelcode(void)
{
    dump_sa_tree(delcode_head,"delcodes");
}

static void undumpdelcode(void)
{
    delcode_head = undump_sa_tree("delcodes");
}

void unsave_math_codes(quarterword grouplevel)
{
    unsavemathcode(grouplevel);
    unsavedelcode(grouplevel);
}

void initialize_math_codes(void)
{
    initializemathcode();
    initializedelcode();
}

void free_math_codes(void)
{
    destroy_sa_tree(mathcode_head);
    destroy_sa_tree(delcode_head);
}

void dump_math_codes(void)
{
    dumpmathcode();
    dumpdelcode();
}

void undump_math_codes(void)
{
    undumpmathcode();
    undumpdelcode();
}
