import csv
import pathlib
import struct

ROOT = pathlib.Path(r"K:/ghidra/Crusader_Decomp")
TARGETS = {189, 190, 191, 272, 273, 283, 285}
TARGET_COMPARE_CLASSES = {"NPCTRIG", "COR_BOOT", "REE_BOOT", "SFXTRIG"}


def find_all(haystack: bytes, needle: bytes) -> list[int]:
    offsets: list[int] = []
    start = 0
    while True:
        found = haystack.find(needle, start)
        if found < 0:
            return offsets
        offsets.append(found)
        start = found + 1

def lcp(left: bytes, right: bytes) -> int:
    count = 0
    limit = min(len(left), len(right))
    while count < limit and left[count] == right[count]:
        count += 1
    return count


def lcs(left: bytes, right: bytes) -> int:
    count = 0
    limit = min(len(left), len(right))
    while count < limit and left[-1 - count] == right[-1 - count]:
        count += 1
    return count


rows = list(
    csv.DictReader(
        (ROOT / "USECODE/EUSECODE_extracted/class_event_index.tsv").open("r", encoding="utf-8"),
        delimiter="\t",
    )
)
rows_by_entry: dict[int, list[dict[str, object]]] = {}
for row in rows:
    entry_index = int(row["entry_index"])
    if entry_index not in TARGETS:
        continue
    if not row["derived_body_start"]:
        continue
    rows_by_entry.setdefault(entry_index, []).append(
        {
            "class_name": row["class_name_hint"],
            "slot": int(row["slot"], 0),
            "event_name_hint": row["event_name_hint"],
            "body_start": int(row["derived_body_start"], 0),
            "body_end": int(row["derived_body_end"], 0),
        }
    )

chunk_files: dict[int, pathlib.Path] = {}
for chunk_path in (ROOT / "USECODE/EUSECODE_extracted/chunks").glob("chunk_*.bin"):
    entry_index = int(chunk_path.name.split("_")[1])
    if entry_index in rows_by_entry:
        chunk_files[entry_index] = chunk_path

bodies: dict[tuple[str, int], bytes] = {}
for entry_index in sorted(rows_by_entry):
    chunk_path = chunk_files[entry_index]
    data = chunk_path.read_bytes()
    class_name = str(rows_by_entry[entry_index][0]["class_name"])
    print(f"ENTRY {entry_index} {class_name} FILE {chunk_path.name}")
    for row in sorted(rows_by_entry[entry_index], key=lambda item: int(item["body_start"])):
        body = data[int(row["body_start"]):int(row["body_end"])]
        class_name = str(row["class_name"])
        slot = int(row["slot"])
        bodies[(class_name, slot)] = body
        hits_0410_16 = find_all(body, struct.pack("<H", 0x0410))
        hits_0410_32 = find_all(body, struct.pack("<I", 0x00000410))
        hits_1004_16 = find_all(body, struct.pack("<H", 0x1004))
        print(
            "BODY class={class_name} slot=0x{slot:02X} hint={hint} start=0x{start:04X} end=0x{end:04X} len={length} le16_0410={count16}:{offs16} le32_00000410={count32}:{offs32} le16_1004={count1004}:{offs1004} first16={first16} last16={last16}".format(
                class_name=class_name,
                slot=slot,
                hint=str(row["event_name_hint"] or "-"),
                start=int(row["body_start"]),
                end=int(row["body_end"]),
                length=len(body),
                count16=len(hits_0410_16),
                offs16=",".join(f"0x{offset:04X}" for offset in hits_0410_16[:16]) or "-",
                count32=len(hits_0410_32),
                offs32=",".join(f"0x{offset:04X}" for offset in hits_0410_32[:16]) or "-",
                count1004=len(hits_1004_16),
                offs1004=",".join(f"0x{offset:04X}" for offset in hits_1004_16[:16]) or "-",
                first16=body[:16].hex(),
                last16=body[-16:].hex(),
            )
        )
    print()

print("TOP_STRUCTURAL_PAIRS")
comparisons: list[tuple[int, int, int, tuple[str, int], tuple[str, int], int, int]] = []
compare_keys = [key for key in bodies if key[0] in TARGET_COMPARE_CLASSES]
for left_index, left_key in enumerate(compare_keys):
    for right_key in compare_keys[left_index + 1:]:
        left_body = bodies[left_key]
        right_body = bodies[right_key]
        prefix = lcp(left_body, right_body)
        suffix = lcs(left_body, right_body)
        comparisons.append((prefix + suffix, prefix, suffix, left_key, right_key, len(left_body), len(right_body)))
comparisons.sort(reverse=True)
for total, prefix, suffix, left_key, right_key, left_len, right_len in comparisons[:12]:
    print(
        f"PAIR {left_key[0]}:0x{left_key[1]:02X} len={left_len} <-> {right_key[0]}:0x{right_key[1]:02X} len={right_len} prefix={prefix} suffix={suffix} total={total}"
    )