// filename: String.cpp
//   author: John Flores
//     date: May, 2003.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
// THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.

#include "String.h"

int String::find(const char *s, int sz) const {
    static unsigned idx = 0;
    String *ptr = const_cast<String *>(this);

    if (ptr != this) {
        ptr = const_cast<String *>(this);
        idx = 0;
    }

    int i;
    while (idx < len) {
        i = 0;
        while (s[i] == buf[i + idx]) {
            i++;
            if (i == sz)
                return idx++;
        }
        idx++;
    }
    idx = 0;
    return NPOS;
}

String String::substr(int idx, int sz) {
    String s;

    if (len - idx - sz < 0)
        sz = len;

    s.set(buf + idx, sz);
    return s;
}


void String::resize(unsigned sz) {
    unsigned newbufsz = bufsz? bufsz: INITSZ;
    while (newbufsz < sz)
        newbufsz *= 2;
    char *newbuf = new char[newbufsz];
    assert(newbuf);
    if (buf) {
        memcpy(newbuf, buf, len + 1);
        delete [] buf;
    }
    buf = newbuf;
    bufsz = newbufsz;
}

String &String::operator=(const char *s) {
    set(s, strlen(s));
    return *this;
}

void String::set(const char *s, unsigned sz) {
    if (bufsz < sz + 1)
        resize(sz + 1);
    memcpy(buf, s, sz);
    buf[len = sz] = '\0';
}


String::String(): buf(NULL), bufsz(0), len(0) {
    set("", 0);
}

String::String(char c): buf(NULL), bufsz(0), len(0) {
    set(&c, 1);
}

String::String(const char *s): buf(NULL), bufsz(0), len(0) {
    set(s, strlen(s));
}

String::String(const String &s): buf(NULL), bufsz(0), len(0) {
    set(s.buf, s.len);
}

String::~String() { 
    delete [] buf;
}

String &String::insert(unsigned idx, char c) {
    return insert(idx, &c, 1);
}

String &String::insert(unsigned idx, const char *s) {
    return insert(idx, s, strlen(s));
}

String &String::insert(unsigned idx, const String &s) {
    return insert(idx, s.buf, s.len);
}

String &String::insert(unsigned idx, const char *s, unsigned sz) {
    assert(idx >= 0 && idx <= len);
    if (bufsz < len + sz + 1)
        resize(len + sz + 1); 
    memmove(buf + idx + sz, buf + idx, len - idx + 1);
    memcpy(buf + idx, s, sz);
    len += sz;
    return *this;
}

String &String::insert(unsigned idx, const String &s, unsigned sz) {
    return insert(idx, s.buf, sz);
}

String &String::remove(int idx, int sz) {
    memmove(buf + idx, buf + idx + sz, len - idx - sz + 1);
    len -= sz;
    return *this;
}