/* code16k.c - Handles Code 16k stacked symbology */

/*
    libzint - the open source barcode library
    Copyright (C) 2008-2016 Robin Stuart <rstuart114@gmail.com>

    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. Neither the name of the project nor the names of its contributors
       may be used to endorse or promote products derived from this software
       without specific prior written permission.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT OWNER OR CONTRIBUTORS 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.
 */

/* Updated to comply with BS EN 12323:2005 */

/* Code 16k can hold up to 77 characters or 154 numbers */

#include <string.h>
#include <stdio.h>
#include <stdlib.h>
#include "common.h"

#define TRUE 1
#define FALSE 0
#define SHIFTA 90
#define LATCHA 91
#define SHIFTB 92
#define LATCHB 93
#define SHIFTC 94
#define LATCHC 95
#define AORB 96
#define ABORC 97
#define CANDB 98
#define CANDBB 99

extern int parunmodd(const unsigned char llyth);

static int list[2][170];

static const char *C16KTable[107] = {
    /* EN 12323 Table 1 - "Code 16K" character encodations */
    "212222", "222122", "222221", "121223", "121322", "131222", "122213",
    "122312", "132212", "221213", "221312", "231212", "112232", "122132", "122231", "113222",
    "123122", "123221", "223211", "221132", "221231", "213212", "223112", "312131", "311222",
    "321122", "321221", "312212", "322112", "322211", "212123", "212321", "232121", "111323",
    "131123", "131321", "112313", "132113", "132311", "211313", "231113", "231311", "112133",
    "112331", "132131", "113123", "113321", "133121", "313121", "211331", "231131", "213113",
    "213311", "213131", "311123", "311321", "331121", "312113", "312311", "332111", "314111",
    "221411", "431111", "111224", "111422", "121124", "121421", "141122", "141221", "112214",
    "112412", "122114", "122411", "142112", "142211", "241211", "221114", "413111", "241112",
    "134111", "111242", "121142", "121241", "114212", "124112", "124211", "411212", "421112",
    "421211", "212141", "214121", "412121", "111143", "111341", "131141", "114113", "114311",
    "411113", "411311", "113141", "114131", "311141", "411131", "211412", "211214", "211232",
    "211133"
};


static const char *C16KStartStop[8] = {
    /* EN 12323 Table 3 and Table 4 - Start patterns and stop patterns */
    "3211", "2221", "2122", "1411", "1132", "1231", "1114", "3112"
};

/* EN 12323 Table 5 - Start and stop values defining row numbers */
static const int C16KStartValues[16] = {
    0, 1, 2, 3, 4, 5, 6, 7, 0, 1, 2, 3, 4, 5, 6, 7
};

static const int C16KStopValues[16] = {
    0, 1, 2, 3, 4, 5, 6, 7, 4, 5, 6, 7, 0, 1, 2, 3
};

static void grwp16(unsigned int *indexliste) {
    int i, j;

    /* bring together same type blocks */
    if (*(indexliste) > 1) {
        i = 1;
        while(i < (int)*(indexliste)) {
            if (list[1][i - 1] == list[1][i]) {
                /* bring together */
                list[0][i - 1] = list[0][i - 1] + list[0][i];
                j = i + 1;

                /* decreace the list */
                while(j < (int)*(indexliste)) {
                    list[0][j - 1] = list[0][j];
                    list[1][j - 1] = list[1][j];
                    j++;
                }
                *(indexliste) = *(indexliste) - 1;
                i--;
            }
            i++;
        }
    }
}

/* Implements rules from ISO 15417 Annex E */
static void dxsmooth16(unsigned int *indexliste) {
    int i, current, last, next, length;

    for(i = 0; i < (int)*(indexliste); i++) {
        current = list[1][i];
        length = list[0][i];
        if (i != 0) {
            last = list[1][i - 1];
        } else {
            last = FALSE;
        }
        if (i != *(indexliste) - 1) {
            next = list[1][i + 1];
        } else {
            next = FALSE;
        }

        if (i == 0) {
            /* first block */
            if ((*(indexliste) == 1) && ((length == 2) && (current == ABORC))) {
                /* Rule 1a */
                list[1][i] = LATCHC;
            }
            if (current == ABORC) {
                if (length >= 4) {
                    /* Rule 1b */
                    list[1][i] = LATCHC;
                } else {
                    list[1][i] = AORB;
                    current = AORB;
                }
            }
            if (current == SHIFTA) {
                /* Rule 1c */
                list[1][i] = LATCHA;
            }
            if ((current == AORB) && (next == SHIFTA)) {
                /* Rule 1c */
                list[1][i] = LATCHA;
                current = LATCHA;
            }
            if (current == AORB) {
                /* Rule 1d */
                list[1][i] = LATCHB;
            }
        } else {
            if ((current == ABORC) && (length >= 4)) {
                /* Rule 3 */
                list[1][i] = LATCHC;
                current = LATCHC;
            }
            if (current == ABORC) {
                list[1][i] = AORB;
                current = AORB;
            }
            if ((current == AORB) && (last == LATCHA)) {
                list[1][i] = LATCHA;
                current = LATCHA;
            }
            if ((current == AORB) && (last == LATCHB)) {
                list[1][i] = LATCHB;
                current = LATCHB;
            }
            if ((current == AORB) && (next == SHIFTA)) {
                list[1][i] = LATCHA;
                current = LATCHA;
            }
            if ((current == AORB) && (next == SHIFTB)) {
                list[1][i] = LATCHB;
                current = LATCHB;
            }
            if (current == AORB) {
                list[1][i] = LATCHB;
                current = LATCHB;
            }
            if ((current == SHIFTA) && (length > 1)) {
                /* Rule 4 */
                list[1][i] = LATCHA;
                current = LATCHA;
            }
            if ((current == SHIFTB) && (length > 1)) {
                /* Rule 5 */
                list[1][i] = LATCHB;
                current = LATCHB;
            }
            if ((current == SHIFTA) && (last == LATCHA)) {
                list[1][i] = LATCHA;
                current = LATCHA;
            }
            if ((current == SHIFTB) && (last == LATCHB)) {
                list[1][i] = LATCHB;
                current = LATCHB;
            }
            if ((current == SHIFTA) && (last == LATCHC)) {
                list[1][i] = LATCHA;
                current = LATCHA;
            }
            if ((current == SHIFTB) && (last == LATCHC)) {
                list[1][i] = LATCHB;
                current = LATCHB;
            }
        } /* Rule 2 is implimented elsewhere, Rule 6 is implied */
    }
    grwp16(indexliste);

}

static void c16k_set_a(const unsigned char source, unsigned int values[], unsigned int *bar_chars) {
    if (source > 127) {
        if (source < 160) {
            values[(*bar_chars)] = source + 64 - 128;
        } else {
            values[(*bar_chars)] = source - 32 - 128;
        }
    } else {
        if (source < 32) {
            values[(*bar_chars)] = source + 64;
        } else {
            values[(*bar_chars)] = source - 32;
        }
    }
    (*bar_chars)++;
}

static void c16k_set_b(const unsigned char source, unsigned int values[], unsigned int *bar_chars) {
    if (source > 127) {
        values[(*bar_chars)] = source - 32 - 128;
    } else {
        values[(*bar_chars)] = source - 32;
    }
    (*bar_chars)++;
}

static void c16k_set_c(const unsigned char source_a, unsigned char source_b, unsigned int values[], unsigned int *bar_chars) {
    int weight;

    weight = (10 * ctoi(source_a)) + ctoi(source_b);
    values[(*bar_chars)] = weight;
    (*bar_chars)++;
}

int code16k(struct zint_symbol *symbol, unsigned char source[], const size_t length) {
    char width_pattern[100];
    int current_row, rows_needed, flip_flop, looper, first_check, second_check;
    int indexchaine, f_state;
    char set[160] = {' '}, fset[160] = {' '}, mode, last_set, current_set;
    unsigned int pads_needed, indexliste, i, j, k, m, read, mx_reader, writer;
    unsigned int values[160] = {0};
    unsigned int bar_characters;
    float glyph_count;
    int errornum, first_sum, second_sum;
    size_t input_length;
    int gs1, c_count;

    errornum = 0;
    strcpy(width_pattern, "");
    input_length = length;

    if (symbol->input_mode == GS1_MODE) {
        gs1 = 1;
    } else {
        gs1 = 0;
    }

    if (input_length > 157) {
        strcpy(symbol->errtxt, "420: Input too long");
        return ZINT_ERROR_TOO_LONG;
    }

    bar_characters = 0;

    /* Detect extended ASCII characters */
    for (i = 0; i < (unsigned int) input_length; i++) {
        if (source[i] >= 128) {
            fset[i] = 'f';
        }
    }
    fset[i] = '\0';

    /* Decide when to latch to extended mode */
    for (i = 0; i < (unsigned int) input_length; i++) {
        j = 0;
        if (fset[i] == 'f') {
            do {
                j++;
            } while (fset[i + j] == 'f');
            if ((j >= 5) || ((j >= 3) && ((i + j) == (input_length - 1)))) {
                for (k = 0; k <= j; k++) {
                    fset[i + k] = 'F';
                }
            }
        }
    }

    /* Decide if it is worth reverting to 646 encodation for a few characters */
    if (input_length > 1) {
        for (i = 1; i < (unsigned int) input_length; i++) {
            if ((fset[i - 1] == 'F') && (fset[i] == ' ')) {
                /* Detected a change from 8859-1 to 646 - count how long for */
                for (j = 0; (fset[i + j] == ' ') && ((i + j) < (unsigned int) input_length); j++);
                if ((j < 5) || ((j < 3) && ((i + j) == (input_length - 1)))) {
                    /* Change to shifting back rather than latching back */
                    for (k = 0; k < j; k++) {
                        fset[i + k] = 'n';
                    }
                }
            }
        }
    }
    /* Detect mode A, B and C characters */
    indexliste = 0;
    indexchaine = 0;

    mode = parunmodd(source[indexchaine]);
    if ((gs1) && (source[indexchaine] == '[')) {
        mode = ABORC;
    } /* FNC1 */

    for (i = 0; i < 160; i++) {
        list[0][i] = 0;
    }

    do {
        list[1][indexliste] = mode;
        while ((list[1][indexliste] == mode) && (indexchaine < input_length)) {
            list[0][indexliste]++;
            indexchaine++;
            mode = parunmodd(source[indexchaine]);
            if ((gs1) && (source[indexchaine] == '[')) {
                mode = ABORC;
            } /* FNC1 */
        }
        indexliste++;
    } while (indexchaine < input_length);

    dxsmooth16(&indexliste);

    /* Put set data into set[] */
    read = 0;
    for (i = 0; i < indexliste; i++) {
        for (j = 0; j < list[0][i]; j++) {
            switch (list[1][i]) {
                case SHIFTA: set[read] = 'a';
                    break;
                case LATCHA: set[read] = 'A';
                    break;
                case SHIFTB: set[read] = 'b';
                    break;
                case LATCHB: set[read] = 'B';
                    break;
                case LATCHC: set[read] = 'C';
                    break;
            }
            read++;
        }
    }

    /* Adjust for strings which start with shift characters - make them latch instead */
    if (set[0] == 'a') {
        i = 0;
        do {
            set[i] = 'A';
            i++;
        } while (set[i] == 'a');
    }

    if (set[0] == 'b') {
        i = 0;
        do {
            set[i] = 'B';
            i++;
        } while (set[i] == 'b');
    }

    /* Watch out for odd-length Mode C blocks */
    c_count = 0;
    for (i = 0; i < read; i++) {
        if (set[i] == 'C') {
            if (source[i] == '[') {
                if (c_count & 1) {
                    if ((i - c_count) != 0) {
                        set[i - c_count] = 'B';
                    } else {
                        set[i - 1] = 'B';
                    }
                }
                c_count = 0;
            } else {
                c_count++;
            }
        } else {
            if (c_count & 1) {
                if ((i - c_count) != 0) {
                    set[i - c_count] = 'B';
                } else {
                    set[i - 1] = 'B';
                }
            }
            c_count = 0;
        }
    }
    if (c_count & 1) {
        if ((i - c_count) != 0) {
            set[i - c_count] = 'B';
        } else {
            set[i - 1] = 'B';
        }
    }
    for (i = 1; i < read - 1; i++) {
        if ((set[i] == 'C') && ((set[i - 1] == 'B') && (set[i + 1] == 'B'))) {
            set[i] = 'B';
        }
    }

    /* Make sure the data will fit in the symbol */
    last_set = ' ';
    glyph_count = 0.0;
    for (i = 0; i < input_length; i++) {
        if ((set[i] == 'a') || (set[i] == 'b')) {
            glyph_count = glyph_count + 1.0;
        }
        if ((fset[i] == 'f') || (fset[i] == 'n')) {
            glyph_count = glyph_count + 1.0;
        }
        if (((set[i] == 'A') || (set[i] == 'B')) || (set[i] == 'C')) {
            if (set[i] != last_set) {
                last_set = set[i];
                glyph_count = glyph_count + 1.0;
            }
        }
        if (i == 0) {
            if ((set[i] == 'B') && (set[1] == 'C')) {
                glyph_count = glyph_count - 1.0;
            }
            if ((set[i] == 'B') && (set[1] == 'B')) {
                if (set[2] == 'C') {
                    glyph_count = glyph_count - 1.0;
                }
            }
            if (fset[i] == 'F') {
                glyph_count = glyph_count + 2.0;
            }
        } else {
            if ((fset[i] == 'F') && (fset[i - 1] != 'F')) {
                glyph_count = glyph_count + 2.0;
            }
            if ((fset[i] != 'F') && (fset[i - 1] == 'F')) {
                glyph_count = glyph_count + 2.0;
            }
        }

        if ((set[i] == 'C') && (!((gs1) && (source[i] == '[')))) {
            glyph_count = glyph_count + 0.5;
        } else {
            glyph_count = glyph_count + 1.0;
        }
    }

    if ((gs1) && (set[0] != 'A')) {
        /* FNC1 can be integrated with mode character */
        glyph_count--;
    }

    if (glyph_count > 77.0) {
        strcpy(symbol->errtxt, "421: Input too long");
        return ZINT_ERROR_TOO_LONG;
    }

    /* Calculate how tall the symbol will be */
    glyph_count = glyph_count + 2.0;
    i = (int)glyph_count;
    rows_needed = (i / 5);
    if (i % 5 > 0) {
        rows_needed++;
    }

    if (rows_needed == 1) {
        rows_needed = 2;
    }

    /* start with the mode character - Table 2 */
    m = 0;
    switch (set[0]) {
        case 'A': m = 0;
            break;
        case 'B': m = 1;
            break;
        case 'C': m = 2;
            break;
    }

    if (symbol->output_options & READER_INIT) {
        if (m == 2) {
            m = 5;
        }
        if (gs1) {
            strcpy(symbol->errtxt, "422: Cannot use both GS1 mode and Reader Initialisation");
            return ZINT_ERROR_INVALID_OPTION;
        } else {
            if ((set[0] == 'B') && (set[1] == 'C')) {
                m = 6;
            }
        }
        values[bar_characters] = (7 * (rows_needed - 2)) + m; /* see 4.3.4.2 */
        values[bar_characters + 1] = 96; /* FNC3 */
        bar_characters += 2;
    } else {
        if (gs1) {
            /* Integrate FNC1 */
            switch (set[0]) {
                case 'B': m = 3;
                    break;
                case 'C': m = 4;
                    break;
            }
        } else {
            if ((set[0] == 'B') && (set[1] == 'C')) {
                m = 5;
            }
            if (((set[0] == 'B') && (set[1] == 'B')) && (set[2] == 'C')) {
                m = 6;
            }
        }
        values[bar_characters] = (7 * (rows_needed - 2)) + m; /* see 4.3.4.2 */
        bar_characters++;
    }

    current_set = set[0];
    f_state = 0;
    /* f_state remembers if we are in Extended ASCII mode (value 1) or
        in ISO/IEC 646 mode (value 0) */
    if (fset[0] == 'F') {
        switch (current_set) {
            case 'A':
                values[bar_characters] = 101;
                values[bar_characters + 1] = 101;
                break;
            case 'B':
                values[bar_characters] = 100;
                values[bar_characters + 1] = 100;
                break;
        }
        bar_characters += 2;
        f_state = 1;
    }

    read = 0;

    /* Encode the data */
    do {

        if ((read != 0) && (set[read] != set[read - 1])) {
            /* Latch different code set */
            switch (set[read]) {
                case 'A':
                    values[bar_characters] = 101;
                    bar_characters++;
                    current_set = 'A';
                    break;
                case 'B':
                    values[bar_characters] = 100;
                    bar_characters++;
                    current_set = 'B';
                    break;
                case 'C':
                    if (!((read == 1) && (set[0] == 'B'))) {
                        /* Not Mode C/Shift B */
                        if (!((read == 2) && ((set[0] == 'B') && (set[1] == 'B')))) {
                            /* Not Mode C/Double Shift B */
                            values[bar_characters] = 99;
                            bar_characters++;
                        }
                    }
                    current_set = 'C';
                    break;
            }
        }

        if (read != 0) {
            if ((fset[read] == 'F') && (f_state == 0)) {
                /* Latch beginning of extended mode */
                switch (current_set) {
                    case 'A':
                        values[bar_characters] = 101;
                        values[bar_characters + 1] = 101;
                        break;
                    case 'B':
                        values[bar_characters] = 100;
                        values[bar_characters + 1] = 100;
                        break;
                }
                bar_characters += 2;
                f_state = 1;
            }
            if ((fset[read] == ' ') && (f_state == 1)) {
                /* Latch end of extended mode */
                switch (current_set) {
                    case 'A':
                        values[bar_characters] = 101;
                        values[bar_characters + 1] = 101;
                        break;
                    case 'B':
                        values[bar_characters] = 100;
                        values[bar_characters + 1] = 100;
                        break;
                }
                bar_characters += 2;
                f_state = 0;
            }
        }

        if ((fset[i] == 'f') || (fset[i] == 'n')) {
            /* Shift extended mode */
            switch (current_set) {
                case 'A':
                    values[bar_characters] = 101; /* FNC 4 */
                    break;
                case 'B':
                    values[bar_characters] = 100; /* FNC 4 */
                    break;
            }
            bar_characters++;
        }

        if ((set[i] == 'a') || (set[i] == 'b')) {
            /* Insert shift character */
            values[bar_characters] = 98;
            bar_characters++;
        }

        if (!((gs1) && (source[read] == '['))) {
            switch (set[read]) { /* Encode data characters */
                case 'A':
                case 'a':
                    c16k_set_a(source[read], values, &bar_characters);
                    read++;
                    break;
                case 'B':
                case 'b':
                    c16k_set_b(source[read], values, &bar_characters);
                    read++;
                    break;
                case 'C': c16k_set_c(source[read], source[read + 1], values, &bar_characters);
                    read += 2;
                    break;
            }
        } else {
            values[bar_characters] = 102;
            bar_characters++;
            read++;
        }
    } while (read < ustrlen(source));

    pads_needed = 5 - ((bar_characters + 2) % 5);
    if (pads_needed == 5) {
        pads_needed = 0;
    }
    if ((bar_characters + pads_needed) < 8) {
        pads_needed += 8 - (bar_characters + pads_needed);
    }
    for (i = 0; i < pads_needed; i++) {
        values[bar_characters] = 106;
        bar_characters++;
    }

    /* Calculate check digits */
    first_sum = 0;
    second_sum = 0;
    for (i = 0; i < bar_characters; i++) {
        first_sum += (i + 2) * values[i];
        second_sum += (i + 1) * values[i];
    }
    first_check = first_sum % 107;
    second_sum += first_check * (bar_characters + 1);
    second_check = second_sum % 107;
    values[bar_characters] = first_check;
    values[bar_characters + 1] = second_check;
    bar_characters += 2;

    for (current_row = 0; current_row < rows_needed; current_row++) {

        strcpy(width_pattern, "");
        strcat(width_pattern, C16KStartStop[C16KStartValues[current_row]]);
        strcat(width_pattern, "1");
        for (i = 0; i < 5; i++) {
            strcat(width_pattern, C16KTable[values[(current_row * 5) + i]]);
        }
        strcat(width_pattern, C16KStartStop[C16KStopValues[current_row]]);

        /* Write the information into the symbol */
        writer = 0;
        flip_flop = 1;
        for (mx_reader = 0; mx_reader < strlen(width_pattern); mx_reader++) {
            for (looper = 0; looper < ctoi(width_pattern[mx_reader]); looper++) {
                if (flip_flop == 1) {
                    set_module(symbol, current_row, writer);
                    writer++;
                } else {
                    writer++;
                }
            }
            if (flip_flop == 0) {
                flip_flop = 1;
            } else {
                flip_flop = 0;
            }
        }
        symbol->row_height[current_row] = 10;
    }

    symbol->rows = rows_needed;
    symbol->width = 70;
    return errornum;
}