"""规范化测试（T-P5）：同义同哈希 / 易变剔除 / 顺序固定 / doc_version 失效 / 多轮不缓存。"""
import hashlib

from gateway.proxy.config import BucketCfg
from gateway.proxy.normalizer import (
    canonical_hash,
    is_cacheable,
    normalize_messages,
    resolve_bucket,
    shape,
)


def _body(content="什么是递归？", role="user", n_extra=0, **over):
    msgs = [{"role": "system", "content": "你是助教"},
            {"role": role, "content": content}]
    for i in range(n_extra):
        msgs.append({"role": "assistant", "content": f"答 {i}"})
    b = {"model": "deepseek-chat", "messages": msgs}
    b.update(over)
    return b


def test_same_semantics_same_hash():
    """同输入同哈希（确定性）+ content 顺序敏感。"""
    b1 = _body()
    b2 = _body()
    assert canonical_hash("default", 1, b1) == canonical_hash("default", 1, b2)
    b3 = _body("什么是递归")            # 差一个问号 -> 不同哈希
    assert canonical_hash("default", 1, b1) != canonical_hash("default", 1, b3)


def test_volatile_fields_stripped():
    """规则 2：temperature/seed 等易变字段不参与哈希；时间戳内容行剔除。"""
    b1 = _body(temperature=0.2, seed=1)
    b2 = _body(temperature=0.9, seed=42)
    assert canonical_hash("default", 1, b1) == canonical_hash("default", 1, b2)
    b3 = _body("当前时间：2026-09-05 10:00:00\n什么是递归？")
    b4 = _body("当前时间：2026-09-06 23:59:59\n什么是递归？")
    assert canonical_hash("default", 1, b3) == canonical_hash("default", 1, b4)


def test_system_template_not_in_hash():
    """规则 3：桶模板/资料前缀不参与哈希——不同模板同哈希。"""
    b = _body()
    assert canonical_hash("python24", 1, b) == canonical_hash("python24", 1, b)
    # 桶不同 -> 键不同（隔离）
    assert canonical_hash("default", 1, b) != canonical_hash("python24", 1, b)


def test_doc_version_bumps_key():
    """doc_version+1 后旧缓存键不可见（资料更新失效）。"""
    b = _body()
    assert canonical_hash("course", 1, b) != canonical_hash("course", 2, b)


def test_multiturn_not_cacheable():
    """规则 5：system 外 >1 条 -> 多轮 cacheable=False（D-P5）。"""
    assert is_cacheable(_body()) is True                    # system+1 user
    assert is_cacheable(_body(n_extra=1)) is False          # +assistant 历史
    assert is_cacheable({"messages": [{"role": "user", "content": "x"}]}) is True


def test_shape_fixed_order_and_template_injection(tmp_path):
    """规则 4：整形顺序 [canonical_system] -> [doc_prefix] -> [原 messages]；
    自带 system 时不重复注入模板；资料前缀文件内容插入。"""
    prefix_file = tmp_path / "python24.txt"
    prefix_file.write_text("第一章：变量与类型", encoding="utf-8")
    bucket = BucketCfg(name="python24", system_template="你是 Python 助教。",
                       doc_prefix_file=str(prefix_file), doc_version=3)
    # 无 system：注入模板 + 资料
    b = {"model": "m", "messages": [{"role": "user", "content": "q"}]}
    shaped = shape(b, bucket)
    roles = [m["role"] for m in shaped["messages"]]
    assert roles == ["system", "system", "user"]
    assert "Python 助教" in shaped["messages"][0]["content"]
    assert "课程资料 v3" in shaped["messages"][1]["content"]
    assert "第一章" in shaped["messages"][1]["content"]
    # 自带 system：模板不重复注入；资料前缀在原 messages 之前（规则 4 顺序）
    b2 = {"model": "m", "messages": [{"role": "system", "content": "自定义"},
                                     {"role": "user", "content": "q"}]}
    shaped2 = shape(b2, bucket)
    assert "课程资料" in shaped2["messages"][0]["content"]
    assert shaped2["messages"][1]["content"] == "自定义"
    # 易变字段剔除
    assert "temperature" not in shape(_body(temperature=0.7), bucket)


def test_resolve_bucket_header_and_fallback():
    """D-P2：X-Campus-Bucket 头优先；未知名回落 default。"""
    from types import SimpleNamespace

    class Cfg:
        def bucket(self, name):
            return SimpleNamespace(name=name or "default")

    r = resolve_bucket(_body(), {"x-campus-bucket": "python24"}, Cfg())
    assert r.name == "python24"
    r2 = resolve_bucket(_body(), {}, Cfg())
    assert r2.name == "default"


def test_normalize_serialization_format():
    """规则 1：role\\u0001content\\u0002 串接形态。"""
    b = {"messages": [{"role": "user", "content": "hi"}]}
    assert normalize_messages(b) == "user\u0001hi\u0002"