import json
from datetime import datetime
from struct import pack
from zoneinfo import ZoneInfo

import numpy as np

NUM_DIGITS = 3144
ARRAY_SIZE = NUM_DIGITS * 10 // 3 + 1
TZ = ZoneInfo("Europe/Paris")
print("Running Spigot Algorithm for pi with:")
print("\t Base: 10_000")
print(f"\t Digits number: {NUM_DIGITS}")
print(f"\t Array length: {ARRAY_SIZE}")
print()

start_time = datetime.now(tz=TZ).strftime("%d/%m/%Y %H:%M:%S")

np.set_printoptions(formatter={"int":hex})
array = np.array([2] * ARRAY_SIZE)
max_carry = 0
max_quotient = 0
max_remainder = 0
print(f"Step 0/{NUM_DIGITS // 4}:")
print("digits = 0000, predigits = 0000, 9999s = 0")
print(array)
print()


def main(f):
    global max_carry, max_quotient, max_remainder
    for step in range(1, NUM_DIGITS // 4 + 1):
        carry = 0
        for i in range(len(array)-1,0,-1):
            x = 10_000 * array[i] + carry
            q = x // (2*i+1)
            r = x % (2 * i + 1)
            max_quotient = max(q, max_quotient)
            max_remainder = max(r, max_remainder)
            array[i] = r
            carry = (x // (2*i+1)) * i
            max_carry = max(carry, max_carry)
        x0 = 10_000 * array[0] + carry
        array[0] = x0 % 10_000
        p = x0 // 10_000

        print(f"Step {step}/{NUM_DIGITS // 4 + 1}:")
        print(f"digits = {p:04d}")
        f.write(pack(">H", p))

    # print(array)
    print()

with open('pi-mock.json', 'w') as f:
    end_time = datetime.now(tz=ZoneInfo("Europe/Paris")).strftime("%d/%m/%Y %H:%M:%S")
    json.dump({
        "start_ts": start_time,
        "end_ts": end_time,
    }, f)
with open('pi-mock.bin', 'wb') as f:
    main(f)

print(f"Max carry: {max_carry}, Max quotient: {max_quotient}, Max remainder: {max_remainder}")