/*

* Long.g - Conversions and parsing for the int64 primitive

*

* Author: u/ApparentlyPlus

*/

import String;

import Char;

module Long {

/*

* ToString - Decimal text for an int64

*/

@intrinsic(stringify_long)

public String func ToString(int64 n) {

if (n == (0 as int64)) { return "0"; }

let neg = n < (0 as int64);

let v = n as uint64;

if (neg) { v = (0 as uint64) - v; }

unsafe {

let [24]char buf;

let i = 24;

while (v > (0 as uint64)) {

i = i - 1;

buf[i] = ('0' + ((v % (10 as uint64)) as int)) as char;

v = v / (10 as uint64);

}

if (neg) { i = i - 1; buf[i] = '-'; }

return String.FromBuffer(&buf[i], 24 - i);

}

}

/*

* Parse - Lenient decimal parse. Returns 0 for null/empty/invalid (mirrors Int.Parse)

*/

public int64 func Parse(String s) {

if (s == null) { return (0 as int64); }

let n = s.Length();

let i = 0;

while (i < n && Char.IsWhitespace(s.CharAt(i))) { i = i + 1; }

let neg = false;

if (i < n && (s.CharAt(i) == '-' || s.CharAt(i) == '+')) {

neg = s.CharAt(i) == '-';

i = i + 1;

}

let result = (0 as uint64);

while (i < n && Char.IsDigit(s.CharAt(i))) {

result = result * (10 as uint64) + (Char.DigitValue(s.CharAt(i)) as uint64);

i = i + 1;

}

if (neg) { return ((0 as uint64) - result) as int64; }

return result as int64;

}

/*

* ParseStrict - Like Parse but throws unless the whole string is a clean integer

*/

public throws int64 func ParseStrict(String s) {

if (s == null) { throw; }

let n = s.Length();

let i = 0;

while (i < n && Char.IsWhitespace(s.CharAt(i))) { i = i + 1; }

let neg = false;

if (i < n && (s.CharAt(i) == '-' || s.CharAt(i) == '+')) {

neg = s.CharAt(i) == '-';

i = i + 1;

}

if (i >= n || !Char.IsDigit(s.CharAt(i))) { throw; }

let result = (0 as uint64);

while (i < n && Char.IsDigit(s.CharAt(i))) {

result = result * (10 as uint64) + (Char.DigitValue(s.CharAt(i)) as uint64);

i = i + 1;

}

while (i < n && Char.IsWhitespace(s.CharAt(i))) { i = i + 1; }

if (i != n) { throw; }

if (neg) { return ((0 as uint64) - result) as int64; }

return result as int64;

}