/*
        / \
      /     \
     |\     / \ / \  chiral software
     |  \ /     \   \
      \  |\     /|  /|
        \|  \ /  |/  |
         |\  |  /|  /
         |  \|/  |/
          \  |  /
            \|/
*/
 
#include <string.h>
#include "extbuf.h"
    
ExtBuf * extbufCreate(long defsize) {
  ExtBuf *eb;
  if(defsize < 1) defsize = 1;
  eb = (ExtBuf *)malloc(sizeof(ExtBuf));
  eb->size = 0; 
  eb->totalSize = defsize; eb->extSize = defsize;
  eb->data = (char *)malloc(defsize);
  eb->data[eb->size] = 0;
  return eb;
}

void extbufFree(ExtBuf *eb) {
  free(eb->data); free(eb);
}

void extbufAppend(ExtBuf *eb, char *b, long rqs) {
  long left = eb->totalSize - eb->size;
  if(left < rqs+1) {
    long newsize = eb->size + (rqs-left) + eb->extSize + 1;
    char *newdata =(char *)malloc(newsize);
    eb->totalSize = newsize;
    memcpy(newdata,eb->data,eb->size);
    free(eb->data);
    eb->data = newdata;
  }
  memcpy(eb->data+eb->size,b,rqs);
  eb->size += rqs;
  eb->data[eb->size] = 0;
}

void extbufAppendChar(ExtBuf *eb, char c) {
  extbufAppend(eb,&c,1);
}

void extbufAppendStr(ExtBuf *eb, char *b) {
  extbufAppend(eb,b,strlen(b));
}

void extbufAppendDecimal(ExtBuf *eb, int n) {
  int digits[64]; // should be big enough to hold 128 bit ints
  int i = 0;
  if(n < 0) {
    extbufAppendChar(eb,'-'); n *= -1;
  }
  while(n > 10) {
    digits[i++] = n % 10;
    n /= 10;
  }
  digits[i] = n;
  while(i >= 0) {
    char c = ((char)digits[i])+'0';
    extbufAppendChar(eb,((char)digits[i])+'0');
    i--;
  }
}

static int intLogTen(int n) {
  int i=0;
  while(n < 10) {
    i++; n /= 10;
  }
  return i;
}

static int intExpTen(int n) {
  int i=1;
  while(n > 0) {
    i *= 10; n--;
  }
  return i;
}