// SPDX-License-Identifier: GPL-3.0-or-later

#include "json.h"

#define JSON_DATES_JS 1
#define JSON_DATES_TIMESTAMP 2

void rrdr2json(RRDR *r, BUFFER *wb, RRDR_OPTIONS options, int datatable) {
    //info("RRD2JSON(): %s: BEGIN", r->st->id);
    int row_annotations = 0, dates, dates_with_new = 0;
    char kq[2] = "",                        // key quote
            sq[2] = "",                     // string quote
            pre_label[101] = "",            // before each label
            post_label[101] = "",           // after each label
            pre_date[101] = "",             // the beginning of line, to the date
            post_date[101] = "",            // closing the date
            pre_value[101] = "",            // before each value
            post_value[101] = "",           // after each value
            post_line[101] = "",            // at the end of each row
            normal_annotation[201] = "",    // default row annotation
            overflow_annotation[201] = "",  // overflow row annotation
            data_begin[101] = "",           // between labels and values
            finish[101] = "",               // at the end of everything
            object_rows_time[101] = "";

    if(datatable) {
        dates = JSON_DATES_JS;
        if( options & RRDR_OPTION_GOOGLE_JSON ) {
            kq[0] = '\0';
            sq[0] = '\'';
        }
        else {
            kq[0] = '"';
            sq[0] = '"';
        }
        row_annotations = 1;
        snprintfz(pre_date,   100, "        {%sc%s:[{%sv%s:%s", kq, kq, kq, kq, sq);
        snprintfz(post_date,  100, "%s}", sq);
        snprintfz(pre_label,  100, ",\n     {%sid%s:%s%s,%slabel%s:%s", kq, kq, sq, sq, kq, kq, sq);
        snprintfz(post_label, 100, "%s,%spattern%s:%s%s,%stype%s:%snumber%s}", sq, kq, kq, sq, sq, kq, kq, sq, sq);
        snprintfz(pre_value,  100, ",{%sv%s:", kq, kq);
        strcpy(post_value,         "}");
        strcpy(post_line,          "]}");
        snprintfz(data_begin, 100, "\n  ],\n    %srows%s:\n [\n", kq, kq);
        strcpy(finish,             "\n]\n}");

        snprintfz(overflow_annotation, 200, ",{%sv%s:%sRESET OR OVERFLOW%s},{%sv%s:%sThe counters have been wrapped.%s}", kq, kq, sq, sq, kq, kq, sq, sq);
        snprintfz(normal_annotation,   200, ",{%sv%s:null},{%sv%s:null}", kq, kq, kq, kq);

        buffer_sprintf(wb, "{\n %scols%s:\n [\n", kq, kq);
        buffer_sprintf(wb, "        {%sid%s:%s%s,%slabel%s:%stime%s,%spattern%s:%s%s,%stype%s:%sdatetime%s},\n", kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, sq, sq);
        buffer_sprintf(wb, "        {%sid%s:%s%s,%slabel%s:%s%s,%spattern%s:%s%s,%stype%s:%sstring%s,%sp%s:{%srole%s:%sannotation%s}},\n", kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, kq, kq, sq, sq);
        buffer_sprintf(wb, "        {%sid%s:%s%s,%slabel%s:%s%s,%spattern%s:%s%s,%stype%s:%sstring%s,%sp%s:{%srole%s:%sannotationText%s}}", kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, sq, sq, kq, kq, kq, kq, sq, sq);

        // remove the valueobjects flag
        // google wants its own keys
        if(options & RRDR_OPTION_OBJECTSROWS)
            options &= ~RRDR_OPTION_OBJECTSROWS;
    }
    else {
        kq[0] = '"';
        sq[0] = '"';
        if(options & RRDR_OPTION_GOOGLE_JSON) {
            dates = JSON_DATES_JS;
            dates_with_new = 1;
        }
        else {
            dates = JSON_DATES_TIMESTAMP;
            dates_with_new = 0;
        }
        if( options & RRDR_OPTION_OBJECTSROWS )
            strcpy(pre_date, " { ");
        else
            strcpy(pre_date, " [ ");
        strcpy(pre_label,  ",\"");
        strcpy(post_label, "\"");
        strcpy(pre_value,  ",");
        if( options & RRDR_OPTION_OBJECTSROWS )
            strcpy(post_line, "}");
        else
            strcpy(post_line, "]");
        snprintfz(data_begin, 100, "],\n    %sdata%s:\n [\n", kq, kq);
        strcpy(finish,             "\n]\n}");

        buffer_sprintf(wb, "{\n %slabels%s: [", kq, kq);
        buffer_sprintf(wb, "%stime%s", sq, sq);

        if( options & RRDR_OPTION_OBJECTSROWS )
            snprintfz(object_rows_time, 100, "%stime%s: ", kq, kq);

    }

    size_t pre_value_len = strlen(pre_value);
    size_t post_value_len = strlen(post_value);
    size_t pre_label_len = strlen(pre_label);
    size_t post_label_len = strlen(post_label);
    size_t pre_date_len = strlen(pre_date);
    size_t post_date_len = strlen(post_date);
    size_t post_line_len = strlen(post_line);
    size_t normal_annotation_len = strlen(normal_annotation);
    size_t overflow_annotation_len = strlen(overflow_annotation);
    size_t object_rows_time_len = strlen(object_rows_time);

    // -------------------------------------------------------------------------
    // print the JSON header

    QUERY_TARGET *qt = r->internal.qt;
    long c, i;
    const long used = qt->query.used;

    // print the header lines
    for(c = 0, i = 0; c < used ; c++) {
        if(unlikely(r->od[c] & RRDR_DIMENSION_HIDDEN)) continue;
        if(unlikely((options & RRDR_OPTION_NONZERO) && !(r->od[c] & RRDR_DIMENSION_NONZERO))) continue;

        buffer_fast_strcat(wb, pre_label, pre_label_len);
        buffer_strcat(wb, string2str(qt->query.array[c].dimension.name));
        buffer_fast_strcat(wb, post_label, post_label_len);
        i++;
    }

    if(!i) {
        buffer_fast_strcat(wb, pre_label, pre_label_len);
        buffer_fast_strcat(wb, "no data", 7);
        buffer_fast_strcat(wb, post_label, post_label_len);
    }
    size_t total_number_of_dimensions = i;

    // print the beginning of row data
    buffer_strcat(wb, data_begin);

    // if all dimensions are hidden, print a null
    if(!i) {
        buffer_strcat(wb, finish);
        return;
    }

    long start = 0, end = rrdr_rows(r), step = 1;
    if(!(options & RRDR_OPTION_REVERSED)) {
        start = rrdr_rows(r) - 1;
        end = -1;
        step = -1;
    }

    // pre-allocate a large enough buffer for us
    // this does not need to be accurate - it is just a hint to avoid multiple realloc().
    buffer_need_bytes(wb,
                      ( 20 * rrdr_rows(r)) // timestamp + json overhead
                    + ( (pre_value_len + post_value_len + 4) * total_number_of_dimensions * rrdr_rows(r) ) // number
                      );

    // for each line in the array
    NETDATA_DOUBLE total = 1;
    for(i = start; i != end ;i += step) {
        NETDATA_DOUBLE *cn = &r->v[ i * r->d ];
        RRDR_VALUE_FLAGS *co = &r->o[ i * r->d ];
        NETDATA_DOUBLE *ar = &r->ar[ i * r->d ];

        time_t now = r->t[i];

        if(dates == JSON_DATES_JS) {
            // generate the local date time
            struct tm tmbuf, *tm = localtime_r(&now, &tmbuf);
            if(!tm) { error("localtime_r() failed."); continue; }

            if(likely(i != start)) buffer_fast_strcat(wb, ",\n", 2);
            buffer_fast_strcat(wb, pre_date, pre_date_len);

            if( options & RRDR_OPTION_OBJECTSROWS )
                buffer_fast_strcat(wb, object_rows_time, object_rows_time_len);

            if(unlikely(dates_with_new))
                buffer_fast_strcat(wb, "new ", 4);

            buffer_jsdate(wb, tm->tm_year + 1900, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min, tm->tm_sec);

            buffer_fast_strcat(wb, post_date, post_date_len);

            if(unlikely(row_annotations)) {
                // google supports one annotation per row
                int annotation_found = 0;
                for(c = 0; c < used ; c++) {
                    if(unlikely(!(r->od[c] & RRDR_DIMENSION_SELECTED))) continue;

                    if(unlikely(co[c] & RRDR_VALUE_RESET)) {
                        buffer_fast_strcat(wb, overflow_annotation, overflow_annotation_len);
                        annotation_found = 1;
                        break;
                    }
                }
                if(likely(!annotation_found))
                    buffer_fast_strcat(wb, normal_annotation, normal_annotation_len);
            }
        }
        else {
            // print the timestamp of the line
            if(likely(i != start))
                buffer_fast_strcat(wb, ",\n", 2);

            buffer_fast_strcat(wb, pre_date, pre_date_len);

            if(unlikely( options & RRDR_OPTION_OBJECTSROWS ))
                buffer_fast_strcat(wb, object_rows_time, object_rows_time_len);

            buffer_rrd_value(wb, (NETDATA_DOUBLE)r->t[i]);

            // in ms
            if(unlikely(options & RRDR_OPTION_MILLISECONDS))
                buffer_fast_strcat(wb, "000", 3);

            buffer_fast_strcat(wb, post_date, post_date_len);
        }

        int set_min_max = 0;
        if(unlikely(options & RRDR_OPTION_PERCENTAGE)) {
            total = 0;
            for(c = 0; c < used ;c++) {
                NETDATA_DOUBLE n;
                if(unlikely(options & RRDR_OPTION_INTERNAL_AR))
                    n = ar[c];
                else
                    n = cn[c];

                if(likely((options & RRDR_OPTION_ABSOLUTE) && n < 0))
                    n = -n;

                total += n;
            }
            // prevent a division by zero
            if(total == 0) total = 1;
            set_min_max = 1;
        }

        // for each dimension
        for(c = 0; c < used ;c++) {
            if(unlikely(r->od[c] & RRDR_DIMENSION_HIDDEN)) continue;
            if(unlikely((options & RRDR_OPTION_NONZERO) && !(r->od[c] & RRDR_DIMENSION_NONZERO))) continue;

            NETDATA_DOUBLE n;
            if(unlikely(options & RRDR_OPTION_INTERNAL_AR))
                n = ar[c];
            else
                n = cn[c];

            buffer_fast_strcat(wb, pre_value, pre_value_len);

            if(unlikely( options & RRDR_OPTION_OBJECTSROWS ))
                buffer_sprintf(wb, "%s%s%s: ", kq, string2str(qt->query.array[c].dimension.name), kq);

            if(co[c] & RRDR_VALUE_EMPTY && !(options & RRDR_OPTION_INTERNAL_AR)) {
                if(unlikely(options & RRDR_OPTION_NULL2ZERO))
                    buffer_fast_strcat(wb, "0", 1);
                else
                    buffer_fast_strcat(wb, "null", 4);
            }
            else {
                if(unlikely((options & RRDR_OPTION_ABSOLUTE) && n < 0))
                    n = -n;

                if(unlikely(options & RRDR_OPTION_PERCENTAGE)) {
                    n = n * 100 / total;

                    if(unlikely(set_min_max)) {
                        r->min = r->max = n;
                        set_min_max = 0;
                    }

                    if(n < r->min) r->min = n;
                    if(n > r->max) r->max = n;
                }

                buffer_rrd_value(wb, n);
            }

            buffer_fast_strcat(wb, post_value, post_value_len);
        }

        buffer_fast_strcat(wb, post_line, post_line_len);
    }

    buffer_strcat(wb, finish);
    //info("RRD2JSON(): %s: END", r->st->id);
}
