"""
Claude Code Provider (Anthropic Direct)

使用 Anthropic 官方 API 调用 Claude 模型
使用 Anthropic Messages API 格式（/v1/messages）

环境变量：
- ANTHROPIC_BASE_URL: API 基础地址（如 https://api.anthropic.com）
- ANTHROPIC_AUTH_TOKEN: API 密钥

注意：
- 使用 Anthropic 原生 Messages API 格式
- 响应格式转换为框架统一的 OpenAI 兼容格式
"""

import os
import json
import asyncio
import logging
import httpx
from typing import List, Dict, Any, Optional

from .usage import TokenUsage
from .pricing import calculate_cost

logger = logging.getLogger(__name__)

# 可重试的异常类型
_RETRYABLE_EXCEPTIONS = (
    httpx.RemoteProtocolError,
    httpx.ConnectError,
    httpx.ReadTimeout,
    httpx.WriteTimeout,
    httpx.ConnectTimeout,
    httpx.PoolTimeout,
    ConnectionError,
)

# 模糊匹配规则：(关键词, 目标模型名)，从精确到宽泛排序
# 精确匹配走 MODEL_EXACT，不命中则按顺序尝试关键词匹配
MODEL_EXACT = {
    "claude-sonnet-4-6": "claude-sonnet-4-6",
    "claude-sonnet-4.6": "claude-sonnet-4-6",
    "claude-sonnet-4-5-20250929": "claude-sonnet-4-5-20250929",
    "claude-sonnet-4-5": "claude-sonnet-4-5-20250929",
    "claude-sonnet-4.5": "claude-sonnet-4-5-20250929",
    "claude-opus-4-6": "claude-opus-4-6",
    "claude-opus-4-5-20251101": "claude-opus-4-5-20251101",
    "claude-opus-4-5": "claude-opus-4-5-20251101",
    "claude-opus-4-1-20250805": "claude-opus-4-1-20250805",
    "claude-opus-4-1": "claude-opus-4-1-20250805",
    "claude-haiku-4-5-20251001": "claude-haiku-4-5-20251001",
    "claude-haiku-4-5": "claude-haiku-4-5-20251001",
}

MODEL_FUZZY = [
    # 版本+家族（精确）
    ("sonnet-4-6", "claude-sonnet-4-6"),
    ("sonnet-4.6", "claude-sonnet-4-6"),
    ("sonnet-4-5", "claude-sonnet-4-5-20250929"),
    ("sonnet-4.5", "claude-sonnet-4-5-20250929"),
    ("opus-4-6", "claude-opus-4-6"),
    ("opus-4.6", "claude-opus-4-6"),
    ("opus-4-5", "claude-opus-4-5-20251101"),
    ("opus-4.5", "claude-opus-4-5-20251101"),
    ("opus-4-1", "claude-opus-4-1-20250805"),
    ("opus-4.1", "claude-opus-4-1-20250805"),
    ("haiku-4-5", "claude-haiku-4-5-20251001"),
    ("haiku-4.5", "claude-haiku-4-5-20251001"),
    # 仅家族名 → 最新版本
    ("sonnet", "claude-sonnet-4-6"),
    ("opus", "claude-opus-4-6"),
    ("haiku", "claude-haiku-4-5-20251001"),
]


def _resolve_model(model: str) -> str:
    """将任意格式的模型名映射为 Anthropic API 接受的模型名。
    支持：OpenRouter 前缀(anthropic/xxx)、带点号(4.5)、纯家族名(sonnet)等。
    """
    # 1. 剥离 provider 前缀
    if "/" in model:
        model = model.split("/", 1)[1]

    # 2. 精确匹配
    if model in MODEL_EXACT:
        return MODEL_EXACT[model]

    # 3. 模糊匹配（大小写不敏感）
    model_lower = model.lower()
    for keyword, target in MODEL_FUZZY:
        if keyword in model_lower:
            logger.info("模型名模糊匹配: %s → %s", model, target)
            return target

    # 4. 兜底：原样返回，让 API 报错
    logger.warning("未能匹配模型名: %s, 原样传递", model)
    return model


def _normalize_tool_call_ids(messages: List[Dict[str, Any]], target_prefix: str) -> List[Dict[str, Any]]:
    """
    将消息历史中的 tool_call_id 统一重写为目标 Provider 的格式。
    跨 Provider 续跑时，历史中的 tool_call_id 可能不兼容目标 API
    （如 Anthropic 的 toolu_xxx 发给 OpenAI，或 OpenAI 的 call_xxx 发给 Anthropic）。
    仅在检测到异格式 ID 时才重写，同格式直接跳过。
    """
    # 第一遍：收集需要重写的 ID
    id_map: Dict[str, str] = {}
    counter = 0
    for msg in messages:
        if msg.get("role") == "assistant" and msg.get("tool_calls"):
            for tc in msg["tool_calls"]:
                old_id = tc.get("id", "")
                if old_id and not old_id.startswith(target_prefix + "_"):
                    if old_id not in id_map:
                        id_map[old_id] = f"{target_prefix}_{counter:06x}"
                        counter += 1

    if not id_map:
        return messages  # 无需重写

    logger.info("重写 %d 个 tool_call_id (target_prefix=%s)", len(id_map), target_prefix)

    # 第二遍：重写（浅拷贝避免修改原始数据）
    result = []
    for msg in messages:
        if msg.get("role") == "assistant" and msg.get("tool_calls"):
            new_tcs = []
            for tc in msg["tool_calls"]:
                old_id = tc.get("id", "")
                if old_id in id_map:
                    new_tcs.append({**tc, "id": id_map[old_id]})
                else:
                    new_tcs.append(tc)
            result.append({**msg, "tool_calls": new_tcs})
        elif msg.get("role") == "tool" and msg.get("tool_call_id") in id_map:
            result.append({**msg, "tool_call_id": id_map[msg["tool_call_id"]]})
        else:
            result.append(msg)

    return result


def _convert_content_to_anthropic(content: Any) -> Any:
    """
    将 OpenAI 格式的 content（字符串或列表）转换为 Anthropic 格式。
    主要处理 image_url 类型块 → Anthropic image 块。
    """
    if not isinstance(content, list):
        return content

    result = []
    for block in content:
        if not isinstance(block, dict):
            result.append(block)
            continue

        block_type = block.get("type", "")
        if block_type == "image_url":
            image_url_obj = block.get("image_url", {})
            url = image_url_obj.get("url", "") if isinstance(image_url_obj, dict) else str(image_url_obj)
            if url.startswith("data:"):
                # base64 编码图片：data:<media_type>;base64,<data>
                header, _, data = url.partition(",")
                media_type = header.split(":")[1].split(";")[0] if ":" in header else "image/png"
                result.append({
                    "type": "image",
                    "source": {
                        "type": "base64",
                        "media_type": media_type,
                        "data": data,
                    },
                })
            else:
                result.append({
                    "type": "image",
                    "source": {
                        "type": "url",
                        "url": url,
                    },
                })
        else:
            result.append(block)
    return result


def _convert_messages_to_anthropic(messages: List[Dict[str, Any]]) -> tuple:
    """
    将 OpenAI 格式消息转换为 Anthropic Messages API 格式

    Returns:
        (system_prompt, anthropic_messages)
    """
    system_prompt = None
    anthropic_messages = []

    for msg in messages:
        role = msg.get("role", "")
        content = msg.get("content", "")

        if role == "system":
            # Anthropic 把 system 消息放在顶层参数中
            system_prompt = content
        elif role == "user":
            anthropic_messages.append({"role": "user", "content": _convert_content_to_anthropic(content)})
        elif role == "assistant":
            assistant_msg = {"role": "assistant"}
            # 处理 tool_calls（assistant 发起工具调用）
            tool_calls = msg.get("tool_calls")
            if tool_calls:
                content_blocks = []
                if content:
                    # content 可能已被 _add_cache_control 转成 list（含 cache_control），
                    # 也可能是普通字符串。两者都需要正确处理，避免产生 {"type":"text","text":[...]}
                    converted = _convert_content_to_anthropic(content)
                    if isinstance(converted, list):
                        content_blocks.extend(converted)
                    elif isinstance(converted, str) and converted.strip():
                        content_blocks.append({"type": "text", "text": converted})
                for tc in tool_calls:
                    func = tc.get("function", {})
                    args_str = func.get("arguments", "{}")
                    try:
                        args = json.loads(args_str) if isinstance(args_str, str) else args_str
                    except json.JSONDecodeError:
                        args = {}
                    content_blocks.append({
                        "type": "tool_use",
                        "id": tc.get("id", ""),
                        "name": func.get("name", ""),
                        "input": args,
                    })
                assistant_msg["content"] = content_blocks
            else:
                assistant_msg["content"] = content
            anthropic_messages.append(assistant_msg)
        elif role == "tool":
            # OpenAI tool 结果 -> Anthropic tool_result
            # Anthropic 要求同一个 assistant 的所有 tool_results 合并到一个 user message 中
            tool_result_block = {
                "type": "tool_result",
                "tool_use_id": msg.get("tool_call_id", ""),
                "content": _convert_content_to_anthropic(content),
            }
            # 如果上一条已经是 tool_result user message，合并进去
            if (anthropic_messages
                    and anthropic_messages[-1].get("role") == "user"
                    and isinstance(anthropic_messages[-1].get("content"), list)
                    and anthropic_messages[-1]["content"]
                    and anthropic_messages[-1]["content"][0].get("type") == "tool_result"):
                anthropic_messages[-1]["content"].append(tool_result_block)
            else:
                anthropic_messages.append({
                    "role": "user",
                    "content": [tool_result_block],
                })

    return system_prompt, anthropic_messages


def _convert_tools_to_anthropic(tools: List[Dict]) -> List[Dict]:
    """将 OpenAI 工具定义转换为 Anthropic 格式"""
    anthropic_tools = []
    for tool in tools:
        if tool.get("type") == "function":
            func = tool["function"]
            anthropic_tools.append({
                "name": func.get("name", ""),
                "description": func.get("description", ""),
                "input_schema": func.get("parameters", {"type": "object", "properties": {}}),
            })
    return anthropic_tools


def _parse_anthropic_response(result: Dict[str, Any]) -> Dict[str, Any]:
    """
    将 Anthropic Messages API 响应转换为框架统一格式

    Anthropic 响应格式:
    {
        "id": "msg_...",
        "type": "message",
        "role": "assistant",
        "content": [{"type": "text", "text": "..."}, {"type": "tool_use", ...}],
        "usage": {"input_tokens": ..., "output_tokens": ...},
        "stop_reason": "end_turn" | "tool_use" | "max_tokens"
    }
    """
    content_blocks = result.get("content", [])

    # 提取文本内容
    text_parts = []
    tool_calls = []
    for block in content_blocks:
        if block.get("type") == "text":
            text_parts.append(block.get("text", ""))
        elif block.get("type") == "tool_use":
            # 转换为 OpenAI tool_calls 格式
            tool_calls.append({
                "id": block.get("id", ""),
                "type": "function",
                "function": {
                    "name": block.get("name", ""),
                    "arguments": json.dumps(block.get("input", {}), ensure_ascii=False),
                },
            })

    content = "\n".join(text_parts)

    # 映射 stop_reason
    stop_reason = result.get("stop_reason", "end_turn")
    finish_reason_map = {
        "end_turn": "stop",
        "tool_use": "tool_calls",
        "max_tokens": "length",
        "stop_sequence": "stop",
    }
    finish_reason = finish_reason_map.get(stop_reason, stop_reason)

    # 提取 usage（Anthropic 原生格式）
    raw_usage = result.get("usage", {})
    usage = TokenUsage(
        input_tokens=raw_usage.get("input_tokens", 0),
        output_tokens=raw_usage.get("output_tokens", 0),
        cache_creation_tokens=raw_usage.get("cache_creation_input_tokens", 0),
        cache_read_tokens=raw_usage.get("cache_read_input_tokens", 0),
    )

    return {
        "content": content,
        "tool_calls": tool_calls if tool_calls else None,
        "finish_reason": finish_reason,
        "usage": usage,
    }


async def claude_code_llm_call(
    messages: List[Dict[str, Any]],
    model: str = "claude-sonnet-4.5",
    tools: Optional[List[Dict]] = None,
    **kwargs
) -> Dict[str, Any]:
    """
    Claude Code (Anthropic) LLM 调用函数

    Args:
        messages: OpenAI 格式消息列表
        model: 模型名称（如 "claude-sonnet-4.5"）
        tools: OpenAI 格式工具定义
        **kwargs: 其他参数（temperature, max_tokens 等）

    Returns:
        统一格式的响应字典
    """
    # base_url = os.getenv("YESCODE_BASE_URL")
    # api_key = os.getenv("YESCODE_API_KEY")
    base_url = os.getenv("ANTHROPIC_BASE_URL")
    api_key = os.getenv("ANTHROPIC_AUTH_TOKEN")

    if not base_url:
        raise ValueError("ANTHROPIC_BASE_URL environment variable not set")
    if not api_key:
        raise ValueError("ANTHROPIC_AUTH_TOKEN environment variable not set")

    base_url = base_url.rstrip("/")
    endpoint = f"{base_url}/v1/messages"

    # 解析模型名
    api_model = _resolve_model(model)

    # 跨 Provider 续跑时，重写不兼容的 tool_call_id
    messages = _normalize_tool_call_ids(messages, "toolu")

    # 转换消息格式
    system_prompt, anthropic_messages = _convert_messages_to_anthropic(messages)

    # 构建 Anthropic 格式请求
    payload = {
        "model": api_model,
        "messages": anthropic_messages,
        "max_tokens": kwargs.get("max_tokens", 16384),
    }

    if system_prompt:
        payload["system"] = system_prompt

    if tools:
        payload["tools"] = _convert_tools_to_anthropic(tools)

    if "temperature" in kwargs:
        payload["temperature"] = kwargs["temperature"]

    headers = {
        "x-api-key": api_key,
        "content-type": "application/json",
        "anthropic-version": "2023-06-01",
        "user-agent": "claude-code/1.0.0",
    }

    # 调用 API（带重试）
    max_retries = 5
    last_exception = None
    for attempt in range(max_retries):
        async with httpx.AsyncClient(timeout=300.0) as client:
            try:
                response = await client.post(endpoint, json=payload, headers=headers)
                response.raise_for_status()
                result = response.json()
                break

            except httpx.HTTPStatusError as e:
                error_body = e.response.text
                status = e.response.status_code
                if status in (429, 500, 502, 503, 504, 524, 529) and attempt < max_retries - 1:
                    wait = 2 ** attempt * 2
                    logger.warning(
                        "[Claude Code] HTTP %d (attempt %d/%d), retrying in %ds: %s",
                        status, attempt + 1, max_retries, wait, error_body[:200],
                    )
                    await asyncio.sleep(wait)
                    last_exception = e
                    continue
                logger.error("[Claude Code] Error %d: %s", status, error_body)
                print(f"[Claude Code] API Error {status}: {error_body[:500]}")
                raise

            except _RETRYABLE_EXCEPTIONS as e:
                last_exception = e
                if attempt < max_retries - 1:
                    wait = 2 ** attempt * 2
                    logger.warning(
                        "[Claude Code] %s (attempt %d/%d), retrying in %ds",
                        type(e).__name__, attempt + 1, max_retries, wait,
                    )
                    await asyncio.sleep(wait)
                    continue
                logger.error("[Claude Code] Request failed after %d attempts: %s", max_retries, e)
                raise

            except Exception as e:
                logger.error("[Claude Code] Request failed: %s", e)
                raise
    else:
        raise last_exception  # type: ignore[misc]

    # 解析 Anthropic 响应并转换为统一格式
    parsed = _parse_anthropic_response(result)
    usage = parsed["usage"]

    # 计算费用
    cost = calculate_cost(model, usage)

    return {
        "content": parsed["content"],
        "tool_calls": parsed["tool_calls"],
        "prompt_tokens": usage.input_tokens,
        "completion_tokens": usage.output_tokens,
        "reasoning_tokens": usage.reasoning_tokens,
        "cache_creation_tokens": usage.cache_creation_tokens,
        "cache_read_tokens": usage.cache_read_tokens,
        "finish_reason": parsed["finish_reason"],
        "cost": cost,
        "usage": usage,
    }


def create_claude_code_llm_call(
    model: str = "claude-sonnet-4.5"
):
    """
    创建 Claude Code (Anthropic) LLM 调用函数

    Args:
        model: 模型名称
            - "claude-sonnet-4.5"

    Returns:
        异步 LLM 调用函数
    """
    async def llm_call(
        messages: List[Dict[str, Any]],
        model: str = model,
        tools: Optional[List[Dict]] = None,
        **kwargs
    ) -> Dict[str, Any]:
        return await claude_code_llm_call(messages, model, tools, **kwargs)

    return llm_call