/*
 * Copyright (C) 2006 Evgeniy Stepanov <eugeni.stepanov@gmail.com>
 *
 * This file is part of libass.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "config.h"

#include <stdlib.h>
#include <stdio.h>
#include <inttypes.h>
#include <ft2build.h>
#include FT_GLYPH_H
#include <strings.h>

#include "ass_library.h"
#include "ass.h"
#include "ass_utils.h"

int mystrtoi(char **p, int *res)
{
    double temp_res;
    char *start = *p;
    temp_res = ass_strtod(*p, p);
    *res = (int) (temp_res + (temp_res > 0 ? 0.5 : -0.5));
    if (*p != start)
        return 1;
    else
        return 0;
}

int mystrtoll(char **p, long long *res)
{
    double temp_res;
    char *start = *p;
    temp_res = ass_strtod(*p, p);
    *res = (int) (temp_res + (temp_res > 0 ? 0.5 : -0.5));
    if (*p != start)
        return 1;
    else
        return 0;
}

int mystrtou32(char **p, int base, uint32_t *res)
{
    char *start = *p;
    *res = strtoll(*p, p, base);
    if (*p != start)
        return 1;
    else
        return 0;
}

int mystrtod(char **p, double *res)
{
    char *start = *p;
    *res = ass_strtod(*p, p);
    if (*p != start)
        return 1;
    else
        return 0;
}

int strtocolor(ASS_Library *library, char **q, uint32_t *res, int hex)
{
    uint32_t color = 0;
    int result;
    char *p = *q;
    int base = hex ? 16 : 10;

    if (*p == '&')
        ++p;
    else
        ass_msg(library, MSGL_DBG2, "suspicious color format: \"%s\"\n", p);

    if (*p == 'H' || *p == 'h') {
        ++p;
        result = mystrtou32(&p, 16, &color);
    } else {
        result = mystrtou32(&p, base, &color);
    }

    {
        unsigned char *tmp = (unsigned char *) (&color);
        unsigned char b;
        b = tmp[0];
        tmp[0] = tmp[3];
        tmp[3] = b;
        b = tmp[1];
        tmp[1] = tmp[2];
        tmp[2] = b;
    }
    if (*p == '&')
        ++p;
    *q = p;

    *res = color;
    return result;
}

// Return a boolean value for a string
char parse_bool(char *str)
{
    while (*str == ' ' || *str == '\t')
        str++;
    if (!strncasecmp(str, "yes", 3))
        return 1;
    else if (strtol(str, NULL, 10) > 0)
        return 1;
    return 0;
}

int parse_ycbcr_matrix(char *str)
{
    while (*str == ' ' || *str == '\t')
        str++;
    if (*str == '\0')
        return YCBCR_DEFAULT;

    char *end = str + strlen(str);
    while (end[-1] == ' ' || end[-1] == '\t')
        end--;

    // Trim a local copy of the input that we know is safe to
    // modify. The buffer is larger than any valid string + NUL,
    // so we can simply chop off the rest of the input.
    char buffer[16];
    size_t n = FFMIN(end - str, sizeof buffer - 1);
    strncpy(buffer, str, n);
    buffer[n] = '\0';

    if (!strcasecmp(buffer, "none"))
        return YCBCR_NONE;
    if (!strcasecmp(buffer, "tv.601"))
        return YCBCR_BT601_TV;
    if (!strcasecmp(buffer, "pc.601"))
        return YCBCR_BT601_PC;
    if (!strcasecmp(buffer, "tv.709"))
        return YCBCR_BT709_TV;
    if (!strcasecmp(buffer, "pc.709"))
        return YCBCR_BT709_PC;
    if (!strcasecmp(buffer, "tv.240m"))
        return YCBCR_SMPTE240M_TV;
    if (!strcasecmp(buffer, "pc.240m"))
        return YCBCR_SMPTE240M_PC;
    if (!strcasecmp(buffer, "tv.fcc"))
        return YCBCR_FCC_TV;
    if (!strcasecmp(buffer, "pc.fcc"))
        return YCBCR_FCC_PC;
    return YCBCR_UNKNOWN;
}

void ass_msg(ASS_Library *priv, int lvl, char *fmt, ...)
{
    va_list va;
    va_start(va, fmt);
    priv->msg_callback(lvl, fmt, va, priv->msg_callback_data);
    va_end(va);
}

unsigned ass_utf8_get_char(char **str)
{
    uint8_t *strp = (uint8_t *) * str;
    unsigned c = *strp++;
    unsigned mask = 0x80;
    int len = -1;
    while (c & mask) {
        mask >>= 1;
        len++;
    }
    if (len <= 0 || len > 4)
        goto no_utf8;
    c &= mask - 1;
    while ((*strp & 0xc0) == 0x80) {
        if (len-- <= 0)
            goto no_utf8;
        c = (c << 6) | (*strp++ & 0x3f);
    }
    if (len)
        goto no_utf8;
    *str = (char *) strp;
    return c;

  no_utf8:
    strp = (uint8_t *) * str;
    c = *strp++;
    *str = (char *) strp;
    return c;
}

/**
 * \brief find style by name
 * \param track track
 * \param name style name
 * \return index in track->styles
 * Returnes 0 if no styles found => expects at least 1 style.
 * Parsing code always adds "Default" style in the end.
 */
int lookup_style(ASS_Track *track, char *name)
{
    int i;
    if (*name == '*')
        ++name;                 // FIXME: what does '*' really mean ?
    for (i = track->n_styles - 1; i >= 0; --i) {
        if (strcmp(track->styles[i].Name, name) == 0)
            return i;
    }
    i = track->default_style;
    ass_msg(track->library, MSGL_WARN,
            "[%p]: Warning: no style named '%s' found, using '%s'",
            track, name, track->styles[i].Name);
    return i;                   // use the first style
}

#ifdef CONFIG_ENCA
void *ass_guess_buffer_cp(ASS_Library *library, unsigned char *buffer,
                          int buflen, char *preferred_language,
                          char *fallback)
{
    const char **languages;
    size_t langcnt;
    EncaAnalyser analyser;
    EncaEncoding encoding;
    char *detected_sub_cp = NULL;
    int i;

    languages = enca_get_languages(&langcnt);
    ass_msg(library, MSGL_V, "ENCA supported languages");
    for (i = 0; i < langcnt; i++) {
        ass_msg(library, MSGL_V, "lang %s", languages[i]);
    }

    for (i = 0; i < langcnt; i++) {
        const char *tmp;

        if (strcasecmp(languages[i], preferred_language) != 0)
            continue;
        analyser = enca_analyser_alloc(languages[i]);
        encoding = enca_analyse_const(analyser, buffer, buflen);
        tmp = enca_charset_name(encoding.charset, ENCA_NAME_STYLE_ICONV);
        if (tmp && encoding.charset != ENCA_CS_UNKNOWN) {
            detected_sub_cp = strdup(tmp);
            ass_msg(library, MSGL_INFO, "ENCA detected charset: %s", tmp);
        }
        enca_analyser_free(analyser);
    }

    free(languages);

    if (!detected_sub_cp) {
        detected_sub_cp = strdup(fallback);
        ass_msg(library, MSGL_INFO,
               "ENCA detection failed: fallback to %s", fallback);
    }

    return detected_sub_cp;
}
#endif
