Replace makeInt with make_int

basicswap/util.py

@@ -9,12 +9,15 @@ import json
 import hashlib
 from .contrib.segwit_addr import bech32_decode, convertbits, bech32_encode
 
+OP_1 = 0x51
+OP_16 = 0x60
 COIN = 100000000
 DCOIN = decimal.Decimal(COIN)
 
 
-def makeInt(v):
-    return int(dquantize(decimal.Decimal(v) * DCOIN).quantize(decimal.Decimal(1)))
+def assert_cond(v, err='Bad opcode'):
+    if not v:
+        raise ValueError(err)
 
 
 def format8(i):
@@ -188,3 +191,105 @@ def DeserialiseNum(b, o=0):
     if b[o + nb - 1] & 0x80:
         return -(v & ~(0x80 << (8 * (nb - 1))))
     return v
+
+
+def decodeScriptNum(script_bytes, o):
+    v = 0
+    num_len = script_bytes[o]
+    if num_len >= OP_1 and num_len <= OP_16:
+        return((num_len - OP_1) + 1, 1)
+
+    if num_len > 4:
+        raise ValueError('Bad scriptnum length')  # Max 4 bytes
+    if num_len + o >= len(script_bytes):
+        raise ValueError('Bad script length')
+    o += 1
+    for i in range(num_len):
+        b = script_bytes[o + i]
+        # Negative flag set in last byte, if num is positive and > 0x80 an extra 0x00 byte will be appended
+        if i == num_len - 1 and b & 0x80:
+            b &= (~(0x80) & 0xFF)
+            v += int(b) << 8 * i
+            v *= -1
+        else:
+            v += int(b) << 8 * i
+    return(v, 1 + num_len)
+
+
+def getCompactSizeLen(v):
+    # Compact Size
+    if v < 253:
+        return 1
+    if v < 0xffff:  # USHRT_MAX
+        return 3
+    if v < 0xffffffff:  # UINT_MAX
+        return 5
+    if v < 0xffffffffffffffff:  # UINT_MAX
+        return 9
+    raise ValueError('Value too large')
+
+
+def make_int(v, precision=8, r=0):  # r = 0, no rounding, fail, r > 0 round up, r < 0 floor
+    if type(v) == float:
+        v = str(v)
+    elif type(v) == int:
+        return v * 10 ** precision
+
+    ep = 10 ** precision
+    have_dp = False
+    rv = 0
+    for c in v:
+        if c == '.':
+            rv *= ep
+            have_dp = True
+            continue
+        if not c.isdigit():
+            raise ValueError('Invalid char')
+        if have_dp:
+            ep //= 10
+            if ep <= 0:
+                if r == 0:
+                    raise ValueError('Mantissa too long')
+                if r > 0:
+                    # Round up
+                    if int(c) > 4:
+                        rv += 1
+                break
+
+            rv += ep * int(c)
+        else:
+            rv = rv * 10 + int(c)
+    if not have_dp:
+        rv *= ep
+    return rv
+
+
+def validate_amount(amount, precision=8):
+    str_amount = str(amount)
+    has_decimal = False
+    for c in str_amount:
+        if c == '.' and not has_decimal:
+            has_decimal = True
+            continue
+        if not c.isdigit():
+            raise ValueError('Invalid amount')
+
+    ar = str_amount.split('.')
+    if len(ar) > 1 and len(ar[1]) > precision:
+        raise ValueError('Too many decimal places in amount {}'.format(str_amount))
+    return True
+
+
+def format_amount(i, display_precision, precision=None):
+    if precision is None:
+        precision = display_precision
+    ep = 10 ** precision
+    n = abs(i)
+    quotient = n // ep
+    remainder = n % ep
+    if display_precision != precision:
+        remainder %= (10 ** display_precision)
+    rv = '{}.{:0>{prec}}'.format(quotient, remainder, prec=display_precision)
+    if i < 0:
+        rv = '-' + rv
+    return rv