/*

 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard

 * Copyright (c) 2007 Mans Rullgard

 *

 * This file is part of FFmpeg.

 *

 * FFmpeg is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * FFmpeg is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with FFmpeg; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

 */

#include <limits.h>

#include <stdarg.h>

#include <stdint.h>

#include <stdio.h>

#include <string.h>

#include "config.h"

#include "mem.h"

#include "avassert.h"

#include "avstring.h"

#include "bprint.h"

#include "error.h"

#include "macros.h"

int av_strstart(const char *str, const char *pfx, const char **ptr)

{

    while (*pfx && *pfx == *str) {

        pfx++;

        str++;

    }

    if (!*pfx && ptr)

        *ptr = str;

    return !*pfx;

}

int av_stristart(const char *str, const char *pfx, const char **ptr)

{

    while (*pfx && av_toupper((unsigned)*pfx) == av_toupper((unsigned)*str)) {

        pfx++;

        str++;

    }

    if (!*pfx && ptr)

        *ptr = str;

    return !*pfx;

}

char *av_stristr(const char *s1, const char *s2)

{

    if (!*s2)

        return (char*)(intptr_t)s1;

    do

        if (av_stristart(s1, s2, NULL))

            return (char*)(intptr_t)s1;

    while (*s1++);

    return NULL;

}

char *av_strnstr(const char *haystack, const char *needle, size_t hay_length)

{

    size_t needle_len = strlen(needle);

    if (!needle_len)

        return (char*)haystack;

    while (hay_length >= needle_len) {

        hay_length--;

        if (!memcmp(haystack, needle, needle_len))

            return (char*)haystack;

        haystack++;

    }

    return NULL;

}

size_t av_strlcpy(char *dst, const char *src, size_t size)

{

    size_t len = 0;

    while (++len < size && *src)

        *dst++ = *src++;

    if (len <= size)

        *dst = 0;

    return len + strlen(src) - 1;

}

size_t av_strlcat(char *dst, const char *src, size_t size)

{

    size_t len = strlen(dst);

    if (size <= len + 1)

        return len + strlen(src);

    return len + av_strlcpy(dst + len, src, size - len);

}

size_t av_strlcatf(char *dst, size_t size, const char *fmt, ...)

{

    size_t len = strlen(dst);

    va_list vl;

    va_start(vl, fmt);

    len += vsnprintf(dst + len, size > len ? size - len : 0, fmt, vl);

    va_end(vl);

    return len;

}

char *av_asprintf(const char *fmt, ...)

{

    char *p = NULL;

    va_list va;

    int len;

    va_start(va, fmt);

    len = vsnprintf(NULL, 0, fmt, va);

    va_end(va);

    if (len < 0)

        goto end;

    p = av_malloc(len + 1);

    if (!p)

        goto end;

    va_start(va, fmt);

    len = vsnprintf(p, len + 1, fmt, va);

    va_end(va);

    if (len < 0)

        av_freep(&p);

end:

    return p;

}

#define WHITESPACES " \n\t\r"

char *av_get_token(const char **buf, const char *term)

{

    char *out     = av_realloc(NULL, strlen(*buf) + 1);

    char *ret     = out, *end = out;

    const char *p = *buf;

    if (!out)

        return NULL;

    p += strspn(p, WHITESPACES);

    while (*p && !strspn(p, term)) {

        char c = *p++;

        if (c == '\\' && *p) {

            *out++ = *p++;

            end    = out;

        } else if (c == '\'') {

            while (*p && *p != '\'')

                *out++ = *p++;

            if (*p) {

                p++;

                end = out;

            }

        } else {

            *out++ = c;

        }

    }

    do

        *out-- = 0;

    while (out >= end && strspn(out, WHITESPACES));

    *buf = p;

    char *small_ret = av_realloc(ret, out - ret + 2);

    return small_ret ? small_ret : ret;

}

char *av_strtok(char *s, const char *delim, char **saveptr)

{

    char *tok;

    if (!s && !(s = *saveptr))

        return NULL;

    /* skip leading delimiters */

    s += strspn(s, delim);

    /* s now points to the first non delimiter char, or to the end of the string */

    if (!*s) {

        *saveptr = NULL;

        return NULL;

    }

    tok = s++;

    /* skip non delimiters */

    s += strcspn(s, delim);

    if (*s) {

        *s = 0;

        *saveptr = s+1;

    } else {

        *saveptr = NULL;

    }

    return tok;

}

int av_strcasecmp(const char *a, const char *b)

{

    uint8_t c1, c2;

    do {

        c1 = av_tolower(*a++);

        c2 = av_tolower(*b++);

    } while (c1 && c1 == c2);

    return c1 - c2;

}

int av_strncasecmp(const char *a, const char *b, size_t n)

{

    uint8_t c1, c2;

    if (n <= 0)

        return 0;

    do {

        c1 = av_tolower(*a++);

        c2 = av_tolower(*b++);

    } while (--n && c1 && c1 == c2);

    return c1 - c2;

}

char *av_strireplace(const char *str, const char *from, const char *to)

{

    char *ret = NULL;

    const char *pstr2, *pstr = str;

    size_t tolen = strlen(to), fromlen = strlen(from);

    AVBPrint pbuf;

    if (!fromlen)

        return av_strdup(str);

    av_bprint_init(&pbuf, 1, AV_BPRINT_SIZE_UNLIMITED);

    while ((pstr2 = av_stristr(pstr, from))) {

        av_bprint_append_data(&pbuf, pstr, pstr2 - pstr);

        pstr = pstr2 + fromlen;

        av_bprint_append_data(&pbuf, to, tolen);

    }

    av_bprint_append_data(&pbuf, pstr, strlen(pstr));

    if (!av_bprint_is_complete(&pbuf)) {

        av_bprint_finalize(&pbuf, NULL);

    } else {

        av_bprint_finalize(&pbuf, &ret);

    }

    return ret;

}

const char *av_basename(const char *path)

{

    if (!path || *path == '\0')

        return ".";

    const char *p = strrchr(path, '/');

#if HAVE_DOS_PATHS

    const char *q = strrchr(path, '\\');

    const char *d = strchr(path, ':');

    p = FFMAX3(p, q, d);

#endif

    if (!p)

        return path;

    return p + 1;

}

const char *av_dirname(char *path)

{

    char *p = path ? strrchr(path, '/') : NULL;

#if HAVE_DOS_PATHS

    char *q = path ? strrchr(path, '\\') : NULL;

    char *d = path ? strchr(path, ':')  : NULL;

    d = d ? d + 1 : d;

    p = FFMAX3(p, q, d);

#endif

    if (!p)

        return ".";

    *p = '\0';

    return path;

}

char *av_append_path_component(const char *path, const char *component)

{

    size_t p_len, c_len;

    char *fullpath;

    if (!path)

        return av_strdup(component);

    if (!component)

        return av_strdup(path);

    p_len = strlen(path);

    c_len = strlen(component);

    if (p_len > SIZE_MAX - c_len || p_len + c_len > SIZE_MAX - 2)

        return NULL;

    fullpath = av_malloc(p_len + c_len + 2);

    if (fullpath) {

        if (p_len) {

            av_strlcpy(fullpath, path, p_len + 1);

            if (c_len) {

                if (fullpath[p_len - 1] != '/' && component[0] != '/')

                    fullpath[p_len++] = '/';

                else if (fullpath[p_len - 1] == '/' && component[0] == '/')

                    p_len--;

            }

        }

        av_strlcpy(&fullpath[p_len], component, c_len + 1);

        fullpath[p_len + c_len] = 0;

    }

    return fullpath;

}

int av_escape(char **dst, const char *src, const char *special_chars,

              enum AVEscapeMode mode, int flags)

{

    AVBPrint dstbuf;

    int ret;

    av_bprint_init(&dstbuf, 1, INT_MAX); /* (int)dstbuf.len must be >= 0 */

    av_bprint_escape(&dstbuf, src, special_chars, mode, flags);

    if (!av_bprint_is_complete(&dstbuf)) {

        av_bprint_finalize(&dstbuf, NULL);

        return AVERROR(ENOMEM);

    }

    if ((ret = av_bprint_finalize(&dstbuf, dst)) < 0)

        return ret;

    return dstbuf.len;

}

int av_match_name(const char *name, const char *names)

{

    const char *p;

    size_t len, namelen;

    if (!name || !names)

        return 0;

    namelen = strlen(name);

    while (*names) {

        int negate = '-' == *names;

        p = strchr(names, ',');

        if (!p)

            p = names + strlen(names);

        names += negate;

        len = FFMAX(p - names, namelen);

        if (!av_strncasecmp(name, names, len) || !strncmp("ALL", names, FFMAX(3, p - names)))

            return !negate;

        names = p + (*p == ',');

    }

    return 0;

}

int av_utf8_decode(int32_t *codep, const uint8_t **bufp, const uint8_t *buf_end,

                   unsigned int flags)

{

    const uint8_t *p = *bufp;

    uint32_t top;

    uint64_t code;

    int ret = 0, tail_len;

    uint32_t overlong_encoding_mins[6] = {

        0x00000000, 0x00000080, 0x00000800, 0x00010000, 0x00200000, 0x04000000,

    };

    if (p >= buf_end)

        return 0;

    code = *p++;

    /* first sequence byte starts with 10, or is 1111-1110 or 1111-1111,

       which is not admitted */

    if ((code & 0xc0) == 0x80 || code >= 0xFE) {

        ret = AVERROR(EILSEQ);

        goto end;

    }

    top = (code & 128) >> 1;

    tail_len = 0;

    while (code & top) {

        int tmp;

        tail_len++;

        if (p >= buf_end) {

            (*bufp) ++;

            return AVERROR(EILSEQ); /* incomplete sequence */

        }

        /* we assume the byte to be in the form 10xx-xxxx */

        tmp = *p++ - 128;   /* strip leading 1 */

        if (tmp>>6) {

            (*bufp) ++;

            return AVERROR(EILSEQ);

        }

        code = (code<<6) + tmp;

        top <<= 5;

    }

    code &= (top << 1) - 1;

    /* check for overlong encodings */

    av_assert0(tail_len <= 5);

    if (code < overlong_encoding_mins[tail_len]) {

        ret = AVERROR(EILSEQ);

        goto end;

    }

    if (code >= 1U<<31) {

        ret = AVERROR(EILSEQ);  /* out-of-range value */

        goto end;

    }

    *codep = code;

    if (code > 0x10FFFF &&

        !(flags & AV_UTF8_FLAG_ACCEPT_INVALID_BIG_CODES))

        ret = AVERROR(EILSEQ);

    if (code < 0x20 && code != 0x9 && code != 0xA && code != 0xD &&

        flags & AV_UTF8_FLAG_EXCLUDE_XML_INVALID_CONTROL_CODES)

        ret = AVERROR(EILSEQ);

    if (code >= 0xD800 && code <= 0xDFFF &&

        !(flags & AV_UTF8_FLAG_ACCEPT_SURROGATES))

        ret = AVERROR(EILSEQ);

    if ((code == 0xFFFE || code == 0xFFFF) &&

        !(flags & AV_UTF8_FLAG_ACCEPT_NON_CHARACTERS))

        ret = AVERROR(EILSEQ);

end:

    *bufp = p;

    return ret;

}

int av_match_list(const char *name, const char *list, char separator)

{

    const char *p, *q;

    for (p = name; p && *p; ) {

        for (q = list; q && *q; ) {

            int k;

            for (k = 0; p[k] == q[k] || (p[k]*q[k] == 0 && p[k]+q[k] == separator); k++)

                if (k && (!p[k] || p[k] == separator))

                    return 1;

            q = strchr(q, separator);

            if(q)

                q++;

        }

        p = strchr(p, separator);

        if (p)

            p++;

    }

    return 0;

}