# -*- coding: utf-8 -*-
"""Разбор логов вылетов Minecraft.

Ищет в логе последний exception-блок и определяет причину:
нехватка ОЗУ, проблемы с Java, конкретный мод или «неизвестно».
"""

import re

# "java.lang.NullPointerException: ..." / "Caused by: ...Exception: ..."
_EXC = re.compile(
    r"^(?:Caused by: |Exception in thread [^\s]+ )?"
    r"([\w.$]+(?:Exception|Error|Throwable))(?::\s*(.*))?$")

_MOD_JAR = re.compile(r"mods[/\\]([\w.\- ]+\.jar)")
_MOD_AT = re.compile(r"\(([\w\-]+)@[\d.]+\)")     # SomeMod@1.2.3 в кадрах
_XMX = re.compile(r"-xmx(\d+)([mg])")


def analyze(text=None, path=None, tail=600):
    """Разбирает лог. Возвращает dict:

    kind    — "crash" | "oom" | "java" | "unknown"
    exc     — класс исключения (без пакета)
    msg     — сообщение исключения
    culprit — имя файла мода (mods/xxx.jar) или id мода, если найдено
    hints   — подсказки ("oom", "xmx=2048", "classver", ...)
    """
    res = {"kind": "unknown", "exc": "", "msg": "", "culprit": None,
           "hints": []}
    lines = []
    if text is not None:
        lines = text.splitlines()[-tail:]
    elif path:
        try:
            with open(path, encoding="utf-8", errors="replace") as f:
                lines = f.readlines()[-tail:]
        except OSError:
            pass
    joined = "\n".join(lines)
    if not joined.strip():
        return res
    low = joined.lower()

    # --- нехватка ОЗУ
    if ("outofmemoryerror" in low
            or "could not reserve enough space" in low
            or "gc overhead limit exceeded" in low):
        res["kind"] = "oom"
        res["exc"] = "OutOfMemoryError"
        res["hints"].append("oom")
        m = _XMX.search(low)
        if m:
            res["hints"].append("xmx=" + m.group(1) + m.group(2))
        return res

    # --- проблемы с Java
    for pat, tag in ((r"unsupported class file major version (\d+)",
                      "classver"),
                     (r"unsupportedclassversionerror", "classver"),
                     (r"could not create the java virtual machine", "jvm"),
                     (r"invalid java runtime|no jvm could be found",
                      "java")):
        if re.search(pat, low):
            res["kind"] = "java"
            res["exc"] = tag
            res["hints"].append(tag)
            return res

    # --- последний exception-блок
    idx = [i for i, ln in enumerate(lines) if _EXC.match(ln.strip())]
    if not idx:
        return res
    caused = [i for i in idx if lines[i].strip().startswith("Caused by:")]
    # корневая причина — последний Caused by в цепочке
    m = _EXC.match(lines[caused[-1] if caused else idx[0]].strip())
    res["kind"] = "crash"
    if m:
        res["exc"] = m.group(1).split(".")[-1]
        res["msg"] = (m.group(2) or "")[:200]

    # --- виновник: файл мода в тексте или mixin-кадр с mod id
    m2 = _MOD_JAR.search(joined)
    if m2:
        res["culprit"] = m2.group(1)
    else:
        m3 = _MOD_AT.search(joined)
        if m3:
            res["culprit"] = m3.group(1)
    return res