import os, sys, collections, math

base = r"F:\steam\steamapps\common\The I of the Dragon\Data\Misc"
files = ["Fonts.dat", "UnitDescription.dat", "AIDescription.dat"]

def printable_ratio(b):
    if not b: return 0
    return sum(1 for x in b if 32 <= x < 127) / len(b)

def score_text(b):
    # rough score: printable ratio + bonus for common english words
    r = printable_ratio(b)
    sample = bytes(b)
    kw = 0
    for w in [b"Char", b"Code", b"Font", b"SpaceWidth", b".tga", b"Shrift", b"Distance", b"Id", b"String"]:
        kw += sample.count(w)
    return r, kw

for f in files:
    p = os.path.join(base, f)
    data = open(p, "rb").read()
    print("="*70)
    print(f, "size", len(data))
    print("first 32:", data[:32].hex(" "))

    # 1) single-byte xor
    best = []
    for k in range(256):
        dec = bytes(x ^ k for x in data)
        r, kw = score_text(dec)
        best.append((kw, r, k, dec[:80]))
    best.sort(key=lambda t: (-t[0], -t[1]))
    print("-- best single-byte XOR by keyword --")
    for kw, r, k, s in best[:5]:
        print(f"  k=0x{k:02X} kw={kw} pr={r:.3f} {s!r}")

    # 2) additive / subtractive
    best = []
    for k in range(256):
        dec = bytes((x - k) & 0xFF for x in data)
        r, kw = score_text(dec)
        best.append((kw, r, k, dec[:80]))
    best.sort(key=lambda t: (-t[0], -t[1]))
    print("-- best subtract key --")
    for kw, r, k, s in best[:3]:
        print(f"  k=0x{k:02X} kw={kw} pr={r:.3f} {s!r}")

    # 3) repeating-key XOR, key length 2..64, derive key from space frequency
    print("-- repeating-key XOR (key from most-common byte == space) --")
    results = []
    for L in range(2, 65):
        key = bytearray()
        for r in range(L):
            col = data[r::L]
            c = collections.Counter(col).most_common(1)[0][0]
            key.append(c ^ 0x20)
        dec = bytes(x ^ key[i % L] for i, x in enumerate(data))
        rr, kw = score_text(dec)
        results.append((kw, rr, L, bytes(key), dec[:80]))
    results.sort(key=lambda t: (-t[0], -t[1]))
    for kw, rr, L, key, s in results[:6]:
        print(f"  L={L:2d} key={key.hex()} kw={kw} pr={rr:.3f} {s!r}")