#include "span.h"

/* C23 only: ISO/IEC 9899:2024. */
#define ST_SPAN_CARET_PAD_CAP 60

void
st_span_print(FILE *out, const struct st_span *span, const char *message)
{
    size_t pad;

    if (out == NULL || span == NULL || span->file == NULL ||
        message == NULL) {
        return;
    }
    fprintf(out, "%s:%zu:%zu: %s\n", span->file, span->line, span->col,
            message);
    /*
     * Caret line: 4-space indent, "..." elision, caret. The caret sits
     * three cells past the reported column (the elision marker occupies
     * those cells), so col 5 renders exactly "    ...^". Columns below
     * 5 collapse onto the elision; columns above 5 push the caret right,
     * capped to keep the line bounded.
     */
    fputs("    ...", out);
    pad = span->col > 5 ? span->col - 5 : 0;
    if (pad > ST_SPAN_CARET_PAD_CAP) {
        pad = ST_SPAN_CARET_PAD_CAP;
    }
    while (pad-- > 0) {
        fputc(' ', out);
    }
    fputs("^\n", out);
}