#include "string_buffer.h"
#include "options.h"
#include "assert.h"

/*****************************************************************************
 *               STRING BUFFER
 * ***************************************************************************/

size_t strchr_count(const char* str, char ch)
{
    if (str == NULL)
        return 0;

    size_t count = 0;
    str = strchr(str, ch);
    while (str) {
        count++;
        str++;
        str = strchr(str, ch);
    }
    return count;
}

const char* str_n_substring_beg(const char* str, char ch_separator, size_t n)
{
    if (str == NULL)
        return NULL;

    if (n == 0)
        return str;

    str = strchr(str, ch_separator);
    --n;
    while (n > 0) {
        if (str == NULL)
            return NULL;
        --n;
        str++;
        str = strchr(str, ch_separator);
    }
    return str ? (str + 1) : NULL;
}

void str_n_substring(const char* str, char ch_separator, size_t n, const char **begin, const char **end)
{
    const char *beg = str_n_substring_beg(str, ch_separator, n);
    if (beg == NULL) {
        *begin = NULL;
        *end = NULL;
        return;
    }

    const char *en = strchr(beg, ch_separator);
    if (en == NULL) {
        en = str + strlen(str);
    }

    *begin = beg;
    *end = en;
    return;
}


string_buffer_t* create_string_buffer(size_t sz)
{
    string_buffer_t *result = (string_buffer_t *)F_MALLOC(sizeof(string_buffer_t));
    if (result == NULL)
        return NULL;
    result->str = F_MALLOC(sz);
    if (result->str == NULL) {
        F_FREE(result);
        return NULL;
    }
    result->str_sz = sz;

    return result;
}

void destroy_string_buffer(string_buffer_t *buffer)
{
    if (buffer == NULL)
        return;
    F_FREE(buffer->str);
    buffer->str = NULL;
    F_FREE(buffer);
}

fort_status_t realloc_string_buffer_without_copy(string_buffer_t *buffer)
{
    assert(buffer);
    char *new_str = (char*)F_MALLOC(buffer->str_sz * 2);
    if (new_str == NULL) {
        return F_MEMORY_ERROR;
    }
    F_FREE(buffer->str);
    buffer->str = new_str;
    buffer->str_sz *= 2;
    return F_SUCCESS;
}

fort_status_t fill_buffer_from_string(string_buffer_t *buffer, const char *str)
{
    assert(buffer);
    assert(str);

    size_t sz = strlen(str);
    char * copy = F_STRDUP(str);
    if (copy == NULL)
        return F_MEMORY_ERROR;

    while (sz >= buffer->str_sz) {
        int status = realloc_string_buffer_without_copy(buffer);
        if (!IS_SUCCESS(status)) {
            return status;
        }
    }
    F_FREE(buffer->str);
    buffer->str = copy;

    return F_SUCCESS;
}



size_t buffer_text_height(string_buffer_t *buffer)
{
    if (buffer == NULL || buffer->str == NULL || strlen(buffer->str) == 0) {
        return 0;
    }
    return 1 + strchr_count(buffer->str, '\n');
}

size_t buffer_text_width(string_buffer_t *buffer)
{
    size_t max_length = 0;
    int n = 0;
    while (1) {
        const char *beg = NULL;
        const char *end = NULL;
        str_n_substring(buffer->str, '\n', n, &beg, &end);
        if (beg == NULL || end == NULL)
            return max_length;

        max_length = MAX(max_length, (end - beg));
        ++n;
    }
}


int buffer_printf(string_buffer_t *buffer, size_t buffer_row, size_t table_column, char *buf, size_t buf_len, const context_t *context)
{
    if (buffer == NULL || buffer->str == NULL
            || buffer_row >= buffer_text_height(buffer) || buf_len == 0) {
        return -1;
    }

    size_t content_width = buffer_text_width(buffer);
    if ((buf_len - 1) < content_width)
        return -1;

    int left = 0;
    int right = 0;

    switch (fort_options_column_alignment(context, table_column)) {
        case LeftAligned:
            left = 0;
            right = (buf_len - 1) - content_width;
            break;
        case CenterAligned:
            left = ((buf_len - 1) - content_width) / 2;
            right = ((buf_len - 1) - content_width) - left;
            break;
        case RightAligned:
            left = (buf_len - 1) - content_width;
            right = 0;
            break;
        default:
            assert(0);
            break;
    }
    if (left < 0 || right < 0)
        return -1;


    int  written = 0;
    written += snprint_n_chars(buf + written, buf_len - written, left, ' ');
    if (written < 0)
        return written;



//    const char *substr = str_n_substring(buffer->str, '\n', buffer_row);
//    if (substr == NULL)
//        return -1;
//    const char *next_substr = str_n_substring(buffer->str, '\n', buffer_row + 1);
//    size_t buf_row_len = 0;
//    if (next_substr) {
//        buf_row_len = next_substr - substr - 1;
//    } else {
//        buf_row_len = strlen(buffer->str) - (next_substr - buffer->str);
//    }   todo
//    if (buf_row_len > content_width)
//        return -1;

//    written += snprintf(buf + written, buf_len - written, "%*s", (int)buf_row_len, substr);
//    if (written < 0)
//        return written;
//    written += snprint_n_chars(buf + written, buf_len - written, content_width - buf_row_len, ' ');
//    if (written < 0)
//        return written;

    const char *beg = NULL;
    const char *end = NULL;
    str_n_substring(buffer->str, '\n', buffer_row, &beg, &end);
    if (beg == NULL || end == NULL)
        return -1;
    char old_value = *end;
    *(char *)end = '\0';

    written += snprintf(buf + written, buf_len - written, "%*s", (int)(end - beg), beg);
    *(char *)end = old_value;
    if (written < 0)
        return written;
    written += snprint_n_chars(buf + written,  buf_len - written, (int)(content_width - (end - beg)), ' ');
    if (written < 0)
        return written;

//    written += snprintf(buf + written, buf_len - written, "%*s", (int)content_width, buffer->str);
//    if (written < 0)
//        return written;

    written += snprint_n_chars(buf + written, buf_len - written, right, ' ');
    return written;
}