"""
A simple wrapper for the official ChatGPT API
"""
import json
import requests
import tiktoken


class Chatbot:
    """
    Official ChatGPT API
    """

    def __init__(
            self,
            api_key: str,
            engine: str = "gpt-3.5-turbo",
            proxy: str = None,
            max_tokens: int = 3000,
            temperature: float = 0.5,
            top_p: float = 1.0,
            presence_penalty: float = 0.0,
            frequency_penalty: float = 0.0,
            reply_count: int = 1,
            system_prompt: str = "You are ChatGPT, a large language model trained by OpenAI. Respond conversationally",
    ) -> None:
        """
        Initialize Chatbot with API key (from https://platform.openai.com/account/api-keys)
        """
        self.engine = engine
        self.session = requests.Session()
        self.api_key = api_key
        self.proxy = proxy

        self.system_prompt = system_prompt
        self.max_tokens = max_tokens
        self.temperature = temperature
        self.top_p = top_p
        self.presence_penalty = presence_penalty
        self.frequency_penalty = frequency_penalty
        self.reply_count = reply_count

        self.sentence = ""
        self.temp = ""
        self.has_printed = False

        if self.proxy:
            proxies = {
                "http": self.proxy,
                "https": self.proxy,
            }
            self.session.proxies = proxies
        self.conversation: dict = {
            "default": [
                {
                    "role": "system",
                    "content": system_prompt,
                },
            ],
        }
        if max_tokens > 4000:
            raise Exception("Max tokens cannot be greater than 4000")

        if self.get_token_count("default") > self.max_tokens:
            raise Exception("System prompt is too long")

    def add_to_conversation(
            self,
            message: str,
            role: str,
            convo_id: str = "default",
    ) -> None:
        """
        Add a message to the conversation
        """
        self.conversation[convo_id].append({"role": role, "content": message})

    def __truncate_conversation(self, convo_id: str = "default") -> None:
        """
        Truncate the conversation
        """
        while True:
            if (
                    self.get_token_count(convo_id) > self.max_tokens
                    and len(self.conversation[convo_id]) > 1
            ):
                # Don't remove the first message
                self.conversation[convo_id].pop(1)
            else:
                break

    # https://github.com/openai/openai-cookbook/blob/main/examples/How_to_count_tokens_with_tiktoken.ipynb
    def get_token_count(self, convo_id: str = "default") -> int:
        """
        Get token count
        """
        if self.engine not in ["gpt-3.5-turbo", "gpt-3.5-turbo-0301"]:
            raise NotImplementedError("Unsupported engine {self.engine}")

        encoding = tiktoken.encoding_for_model(self.engine)

        num_tokens = 0
        for message in self.conversation[convo_id]:
            # every message follows <im_start>{role/name}\n{content}<im_end>\n
            num_tokens += 4
            for key, value in message.items():
                num_tokens += len(encoding.encode(value))
                if key == "name":  # if there's a name, the role is omitted
                    num_tokens += -1  # role is always required and always 1 token
        num_tokens += 2  # every reply is primed with <im_start>assistant
        return num_tokens

    def get_max_tokens(self, convo_id: str) -> int:
        """
        Get max tokens
        """
        return self.max_tokens - self.get_token_count(convo_id)

    def ask_stream(
            self,
            prompt: str,
            lock=None,
            stop_event=None,
            role: str = "user",
            convo_id: str = "default",
    ) -> None:
        """
        Ask a question
        """
        self.has_printed = False
        # Make conversation if it doesn't exist
        if convo_id not in self.conversation:
            self.reset(convo_id=convo_id, system_prompt=self.system_prompt)
        self.add_to_conversation(prompt, "user", convo_id=convo_id)
        self.__truncate_conversation(convo_id=convo_id)
        # Get response
        response = self.session.post(
            "https://api.openai.com/v1/chat/completions",
            headers={"Authorization": f"Bearer {self.api_key}"},
            json={
                "model": self.engine,
                "messages": self.conversation[convo_id],
                "stream": True,
                "temperature": self.temperature,
                "top_p": self.top_p,
                "presence_penalty":
                    self.presence_penalty,
                "frequency_penalty":
                    self.frequency_penalty,
                "n": self.reply_count,
                "user": role,
                "max_tokens": self.get_max_tokens(convo_id=convo_id),
            },
            stream=True,
        )
        if response.status_code != 200:
            raise Exception(
                f"Error: {response.status_code} {response.reason} {response.text}",
            )
        response_role: str = None
        full_response: str = ""

        for line in response.iter_lines():
            if stop_event.is_set():
                self.temp = ""
                return
            if not line:
                continue
            # Remove "data: "
            line = line.decode("utf-8")[6:]
            if line == "[DONE]":
                break
            resp: dict = json.loads(line)
            choices = resp.get("choices")
            if not choices:
                continue
            delta = choices[0].get("delta")
            if not delta:
                continue
            if "role" in delta:
                response_role = delta["role"]
            if "content" in delta:
                content = delta["content"]  # .replace(" ", "") # （只能用于汉语发音严重不连续的情况，英文会导致空格丢失）
                success = lock.acquire(blocking=False)
                if success:
                    try:
                        self.sentence += self.temp + content  # 确保每次别的线程都能拿到完整的句子，但是会保留前面的句子
                        self.temp = ""
                    finally:
                        lock.release()
                else:
                    self.temp += content
                print(content, end="")
                full_response += content
        print()
        self.has_printed = True
        self.add_to_conversation(full_response, response_role, convo_id=convo_id)

    def rollback(self, n: int = 1, convo_id: str = "default") -> None:
        """
        Rollback the conversation
        """
        for _ in range(n):
            self.conversation[convo_id].pop()

    def reset(self, convo_id: str = "default", system_prompt: str = None) -> None:
        """
        Reset the conversation
        """
        self.conversation[convo_id] = [
            {"role": "system", "content": system_prompt or self.system_prompt},
        ]

    def save(self, file: str, *convo_ids: str) -> bool:
        """
        Save the conversation to a JSON file
        """
        try:
            with open(file, "w", encoding="utf-8") as f:
                if convo_ids:
                    json.dump({k: self.conversation[k] for k in convo_ids}, f, indent=2)
                else:
                    json.dump(self.conversation, f, indent=2)
        except (FileNotFoundError, KeyError):
            return False
        return True
        # print(f"Error: {file} could not be created")

    def load(self, file: str, *convo_ids: str) -> bool:
        """
        Load the conversation from a JSON  file
        """
        try:
            with open(file, encoding="utf-8") as f:
                if convo_ids:
                    convos = json.load(f)
                    self.conversation.update({k: convos[k] for k in convo_ids})
                else:
                    self.conversation = json.load(f)
        except (FileNotFoundError, KeyError, json.decoder.JSONDecodeError):
            return False
        return True

    def load_config(self, file: str, no_api_key: bool = False) -> bool:
        """
        Load the configuration from a JSON file
        """
        try:
            with open(file, encoding="utf-8") as f:
                config = json.load(f)
                if config is not None:
                    self.api_key = config.get("api_key") or self.api_key
                    if self.api_key is None:
                        # Make sure the API key is set
                        raise Exception("Error: API key is not set")
                    self.engine = config.get("engine") or self.engine
                    self.temperature = config.get("temperature") or self.temperature
                    self.top_p = config.get("top_p") or self.top_p
                    self.presence_penalty = (
                            config.get("presence_penalty") or self.presence_penalty
                    )
                    self.frequency_penalty = (
                            config.get("frequency_penalty") or self.frequency_penalty
                    )
                    self.reply_count = config.get("reply_count") or self.reply_count
                    self.max_tokens = config.get("max_tokens") or self.max_tokens

                    if config.get("system_prompt") is not None:
                        self.system_prompt = (
                                config.get("system_prompt") or self.system_prompt
                        )
                        self.reset(system_prompt=self.system_prompt)

                    if config.get("proxy") is not None:
                        self.proxy = config.get("proxy") or self.proxy
                        proxies = {
                            "http": self.proxy,
                            "https": self.proxy,
                        }
                        self.session.proxies = proxies
        except (FileNotFoundError, KeyError, json.decoder.JSONDecodeError):
            return False
        return True
