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#include "compression.h"
using math::wide_integer::uint512_t;
uint512_t decodeBase(int b, const char *str);
const char* digits = " 0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-./?@";
// This function is from aprs434.github.io,
// MIT License, Copyright (c) 2022 Serge Y. Stroobandt, ON4AA
uint32_t encodeCallsign(const char *callsign) {
// Encode CCCC according to aprs434.github.io/code/codec.cpp
const int b = 37;
uint32_t result;
uint32_t weight;
int i, j, k, ch;
result = 0, weight = 1;
for (i = j = strlen(callsign); i > 0; i--) { // iterate over input string
ch = toupper(callsign[i-1]);
for (k = 0; k < strlen(digits); k++) { // lookup char index
if (digits[k] == ch) {
break;
}
}
if (k == strlen(digits)) // ignore if ch not found in digits
continue;
result = result + ((k) * weight);
weight = weight * b;
}
return result; // result can be pow(42,51)!
}
// This function is from ESP32 lora.tracker,
// MIT License, Copyright (c) 2020 Peter Buchegger
void ax25_base91enc(char *s, uint8_t n, uint32_t v) {
/* Creates a Base-91 representation of the value in v in the string
* pointed to by s, n-characters long. String length should be n+1.
*/
for (s += n, *s = '\0'; n; n--) {
*(--s) = v % 91 + 33;
v /= 91;
}
}
static void strrev(char s[])
{
int length = strlen(s) ;
int c, i, j;
for (i = 0, j = length - 1; i < j; i++, j--)
{
c = s[i];
s[i] = s[j];
s[j] = c;
}
}
inline void assert(bool cond) {
while (!cond) {}
}
static uint8_t bytes[100];
uint512_t decodeBase(int b, const char* str) { // base b, str 64 bytes max '\0' terminated
uint512_t result;
uint512_t weight;
int i, j, k, ch;
assert(b <= strlen(digits));
assert(b > 1);
result = 0, weight = 1;
for (i = j = strlen(str); i > 0; i--) // iterate over input string
{
ch=toupper(str[i-1]);
for (k = 0; k < strlen(digits); k++) { //lookup char index
if (digits[k] == ch) {
break;
}
}
if (k == strlen(digits)) // ignore if ch not found in digits
continue;
result = result + ((k) * weight);
weight = weight * b;
}
return result; // result can be pow(42,51)!
}
uint512_t encodetttt(const char *s) {
return decodeBase(42, s);
}
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