from dataclasses import dataclass
from typing import TYPE_CHECKING, Dict, List, Optional, Sequence, Tuple, Union

from ..extras.logging import get_logger
from .formatter import EmptyFormatter, FunctionFormatter, StringFormatter, ToolFormatter
from .utils import Role, infer_max_len


if TYPE_CHECKING:
    from transformers import PreTrainedTokenizer

    from .formatter import Formatter


logger = get_logger(__name__)


@dataclass
class Template:
    format_user: "Formatter"
    format_assistant: "Formatter"
    format_system: "Formatter"
    format_function: "Formatter"
    format_observation: "Formatter"
    format_tools: "Formatter"
    format_separator: "Formatter"
    default_system: str
    stop_words: List[str]
    efficient_eos: bool
    replace_eos: bool
    force_system: bool

    def encode_oneturn(
        self,
        tokenizer: "PreTrainedTokenizer",
        messages: List[Dict[str, str]],
        system: Optional[str] = None,
        tools: Optional[str] = None,
        cutoff_len: Optional[int] = 1_000_000,
        reserved_label_len: Optional[int] = 1,
    ) -> Tuple[List[int], List[int]]:
        r"""
        Returns a single pair of token ids representing prompt and response respectively.
        """
        encoded_pairs = self._encode(tokenizer, messages, system, tools, cutoff_len, reserved_label_len)
        prompt_ids = []
        for query_ids, resp_ids in encoded_pairs[:-1]:
            prompt_ids += query_ids + resp_ids
        prompt_ids = prompt_ids + encoded_pairs[-1][0]
        answer_ids = encoded_pairs[-1][1]
        return prompt_ids, answer_ids

    def encode_multiturn(
        self,
        tokenizer: "PreTrainedTokenizer",
        messages: List[Dict[str, str]],
        system: Optional[str] = None,
        tools: Optional[str] = None,
        cutoff_len: Optional[int] = 1_000_000,
        reserved_label_len: Optional[int] = 1,
    ) -> Sequence[Tuple[List[int], List[int]]]:
        r"""
        Returns multiple pairs of token ids representing prompts and responses respectively.
        """
        return self._encode(tokenizer, messages, system, tools, cutoff_len, reserved_label_len)

    def _encode(
        self,
        tokenizer: "PreTrainedTokenizer",
        messages: List[Dict[str, str]],
        system: str,
        tools: str,
        cutoff_len: int,
        reserved_label_len: int,
    ) -> Sequence[Tuple[List[int], List[int]]]:
        r"""
        Encodes formatted inputs to pairs of token ids.
        Turn 0: system + query        resp
        Turn t: sep + query           resp
        """
        system = system or self.default_system
        encoded_messages = []
        for i, message in enumerate(messages):
            elements = []
            if i == 0 and (system or tools or self.force_system):
                tool_text = self.format_tools.apply(content=tools)[0] if tools else ""
                elements += self.format_system.apply(content=(system + tool_text))
            elif i > 0 and i % 2 == 0:
                elements += self.format_separator.apply()

            if message["role"] == Role.USER:
                elements += self.format_user.apply(content=message["content"], idx=str(i // 2))
            elif message["role"] == Role.ASSISTANT:
                elements += self.format_assistant.apply(content=message["content"])
            elif message["role"] == Role.OBSERVATION:
                elements += self.format_observation.apply(content=message["content"])
            elif message["role"] == Role.FUNCTION:
                elements += self.format_function.apply(content=message["content"])
            else:
                raise NotImplementedError

            encoded_messages.append(self._convert_elements_to_ids(tokenizer, elements))

        return self._make_pairs(encoded_messages, cutoff_len, reserved_label_len)

    def _convert_elements_to_ids(
        self, tokenizer: "PreTrainedTokenizer", elements: List[Union[str, Dict[str, str]]]
    ) -> List[int]:
        r"""
        Converts elements to token ids.
        """
        token_ids = []
        for elem in elements:
            if isinstance(elem, str):
                if len(elem) != 0:
                    token_ids += tokenizer.encode(elem, add_special_tokens=False)
            elif isinstance(elem, dict):
                token_ids += [tokenizer.convert_tokens_to_ids(elem.get("token"))]
            elif isinstance(elem, set):
                if "bos_token" in elem and tokenizer.bos_token_id is not None:
                    token_ids += [tokenizer.bos_token_id]
                elif "eos_token" in elem and tokenizer.eos_token_id is not None:
                    token_ids += [tokenizer.eos_token_id]
            else:
                raise ValueError("Input must be string, set[str] or dict[str, str], got {}".format(type(elem)))

        return token_ids

    def _make_pairs(
        self,
        encoded_messages: Sequence[List[int]],
        cutoff_len: int,
        reserved_label_len: int,
    ) -> Sequence[Tuple[List[int], List[int]]]:
        encoded_pairs = []
        total_length = 0
        for i in range(0, len(encoded_messages), 2):
            if total_length >= cutoff_len:
                break

            max_source_len, max_target_len = infer_max_len(
                source_len=len(encoded_messages[i]),
                target_len=len(encoded_messages[i + 1]),
                max_len=(cutoff_len - total_length),
                reserved_label_len=reserved_label_len,
            )
            source_ids = encoded_messages[i][:max_source_len]
            target_ids = encoded_messages[i + 1][:max_target_len]
            total_length += len(source_ids) + len(target_ids)
            encoded_pairs.append((source_ids, target_ids))

        return encoded_pairs


@dataclass
class Llama2Template(Template):
    def _encode(
        self,
        tokenizer: "PreTrainedTokenizer",
        messages: List[Dict[str, str]],
        system: str,
        tools: str,
        cutoff_len: int,
        reserved_label_len: int,
    ) -> Sequence[Tuple[List[int], List[int]]]:
        r"""
        Encodes formatted inputs to pairs of token ids.
        Turn 0: system + query        resp
        Turn t: sep + query           resp
        """
        system = system or self.default_system
        encoded_messages = []
        for i, message in enumerate(messages):
            elements = []
            system_text = ""
            if i == 0 and (system or tools or self.force_system):
                tool_text = self.format_tools.apply(content=tools)[0] if tools else ""
                system_text = self.format_system.apply(content=(system + tool_text))[0]
            elif i > 0 and i % 2 == 0:
                elements += self.format_separator.apply()

            if message["role"] == Role.USER:
                elements += self.format_user.apply(content=system_text + message["content"])
            elif message["role"] == Role.ASSISTANT:
                elements += self.format_assistant.apply(content=message["content"])
            elif message["role"] == Role.OBSERVATION:
                elements += self.format_observation.apply(content=message["content"])
            elif message["role"] == Role.FUNCTION:
                elements += self.format_function.apply(content=message["content"])
            else:
                raise NotImplementedError

            encoded_messages.append(self._convert_elements_to_ids(tokenizer, elements))

        return self._make_pairs(encoded_messages, cutoff_len, reserved_label_len)


templates: Dict[str, Template] = {}


def _register_template(
    name: str,
    format_user: Optional["Formatter"] = None,
    format_assistant: Optional["Formatter"] = None,
    format_system: Optional["Formatter"] = None,
    format_function: Optional["Formatter"] = None,
    format_observation: Optional["Formatter"] = None,
    format_tools: Optional["Formatter"] = None,
    format_separator: Optional["Formatter"] = None,
    default_system: Optional[str] = "",
    stop_words: Optional[List[str]] = [],
    efficient_eos: Optional[bool] = False,
    replace_eos: Optional[bool] = False,
    force_system: Optional[bool] = False,
) -> None:
    eos_slots = [] if efficient_eos else [{"eos_token"}]
    template_class = Llama2Template if name.startswith("llama2") else Template
    default_user_formatter = StringFormatter(slots=["{{content}}"])
    default_assistant_formatter = StringFormatter(slots=["{{content}}"] + eos_slots)
    default_function_formatter = FunctionFormatter(slots=["Action: {{name}}\nAction Input: {{arguments}}"] + eos_slots)
    default_tool_formatter = ToolFormatter(tool_format="default")
    default_separator_formatter = EmptyFormatter()
    templates[name] = template_class(
        format_user=format_user or default_user_formatter,
        format_assistant=format_assistant or default_assistant_formatter,
        format_system=format_system or default_user_formatter,
        format_function=format_function or default_function_formatter,
        format_observation=format_observation or format_user or default_user_formatter,
        format_tools=format_tools or default_tool_formatter,
        format_separator=format_separator or default_separator_formatter,
        default_system=default_system,
        stop_words=stop_words,
        efficient_eos=efficient_eos,
        replace_eos=replace_eos,
        force_system=force_system,
    )


def _add_or_replace_eos_token(tokenizer: "PreTrainedTokenizer", eos_token: str) -> None:
    is_added = tokenizer.eos_token_id is None
    is_oov = eos_token not in tokenizer.get_vocab()
    tokenizer.add_special_tokens({"eos_token": eos_token})

    if is_added:
        logger.info("Add eos token: {}".format(tokenizer.eos_token))
    else:
        logger.info("Replace eos token: {}".format(tokenizer.eos_token))

    if is_oov:
        logger.warning("New tokens have been added, make sure `resize_vocab` is True.")


def get_template_and_fix_tokenizer(
    tokenizer: "PreTrainedTokenizer",
    name: Optional[str] = None,
) -> Template:
    if name is None:
        template = templates["vanilla"]  # placeholder
    else:
        template = templates.get(name, None)
        if templates is None:
            raise ValueError("Template {} does not exist.".format(name))

    stop_words = template.stop_words
    if template.replace_eos:
        if not stop_words:
            raise ValueError("Stop words are required to replace the EOS token.")

        _add_or_replace_eos_token(tokenizer, eos_token=stop_words[0])
        stop_words = stop_words[1:]

    if tokenizer.eos_token_id is None:
        _add_or_replace_eos_token(tokenizer, eos_token="<|endoftext|>")

    if tokenizer.pad_token_id is None:
        tokenizer.pad_token = tokenizer.eos_token
        logger.info("Add pad token: {}".format(tokenizer.pad_token))

    if stop_words:
        tokenizer.add_special_tokens(
            dict(additional_special_tokens=stop_words), replace_additional_special_tokens=False
        )
        logger.info("Add {} to stop words.".format(",".join(stop_words)))

    return template


_register_template(
    name="alpaca",
    format_user=StringFormatter(slots=["### Instruction:\n{{content}}\n\n### Response:\n"]),
    format_separator=EmptyFormatter(slots=["\n\n"]),
    default_system=(
        "Below is an instruction that describes a task. " "Write a response that appropriately completes the request."
    ),
)


_register_template(
    name="aquila",
    format_user=StringFormatter(slots=["Human: {{content}}###Assistant:"]),
    format_separator=EmptyFormatter(slots=["###"]),
    default_system=(
        "A chat between a curious human and an artificial intelligence assistant. "
        "The assistant gives helpful, detailed, and polite answers to the human's questions."
    ),
    stop_words=["</s>"],
    efficient_eos=True,
)


_register_template(
    name="baichuan",
    format_user=StringFormatter(slots=[{"token": "<reserved_102>"}, "{{content}}", {"token": "<reserved_103>"}]),
    efficient_eos=True,
)


_register_template(
    name="baichuan2",
    format_user=StringFormatter(slots=[{"token": "<reserved_106>"}, "{{content}}", {"token": "<reserved_107>"}]),
    efficient_eos=True,
)


_register_template(
    name="belle",
    format_user=StringFormatter(slots=["Human: {{content}}\n\nBelle: "]),
    format_system=StringFormatter(slots=[{"bos_token"}, "{{content}}"]),
    format_separator=EmptyFormatter(slots=["\n\n"]),
    force_system=True,
)


_register_template(
    name="bluelm",
    format_user=StringFormatter(slots=[{"token": "[|Human|]:"}, "{{content}}", {"token": "[|AI|]:"}]),
)


_register_template(
    name="chatglm2",
    format_user=StringFormatter(slots=["[Round {{idx}}]\n\n问：{{content}}\n\n答："]),
    format_system=StringFormatter(slots=[{"token": "[gMASK]"}, {"token": "sop"}, "{{content}}"]),
    format_separator=EmptyFormatter(slots=["\n\n"]),
    efficient_eos=True,
    force_system=True,
)


_register_template(
    name="chatglm3",
    format_user=StringFormatter(slots=[{"token": "<|user|>"}, "\n", "{{content}}", {"token": "<|assistant|>"}]),
    format_assistant=StringFormatter(slots=["\n", "{{content}}"]),
    format_system=StringFormatter(
        slots=[{"token": "[gMASK]"}, {"token": "sop"}, {"token": "<|system|>"}, "\n", "{{content}}"]
    ),
    format_function=FunctionFormatter(slots=["{{name}}\n{{arguments}}"]),
    format_observation=StringFormatter(
        slots=[{"token": "<|observation|>"}, "\n", "{{content}}", {"token": "<|assistant|>"}]
    ),
    default_system=(
        "You are ChatGLM3, a large language model trained by Zhipu.AI. "
        "Follow the user's instructions carefully. Respond using markdown."
    ),
    stop_words=["<|user|>", "<|observation|>"],
    efficient_eos=True,
)


_register_template(
    name="chatml_de",
    format_user=StringFormatter(slots=["<|im_start|>user\n{{content}}<|im_end|>\n<|im_start|>assistant\n"]),
    format_system=StringFormatter(slots=["<|im_start|>system\n{{content}}<|im_end|>\n"]),
    format_separator=EmptyFormatter(slots=["\n"]),
    default_system="Du bist ein freundlicher und hilfsbereiter KI-Assistent.",
    stop_words=["<|im_end|>"],
    replace_eos=True,
)


_register_template(
    name="codegeex2",
    format_system=StringFormatter(slots=[{"token": "[gMASK]"}, {"token": "sop"}, "{{content}}"]),
    force_system=True,
)


_register_template(
    name="cpm",
    format_user=StringFormatter(slots=["<用户>{{content}}<AI>"]),
    format_system=StringFormatter(slots=[{"bos_token"}, "{{content}}"]),
    force_system=True,
)


_register_template(
    name="deepseek",
    format_user=StringFormatter(slots=["User: {{content}}\n\nAssistant:"]),
    format_system=StringFormatter(slots=[{"bos_token"}, "{{content}}"]),
    force_system=True,
)


_register_template(
    name="deepseekcoder",
    format_user=StringFormatter(slots=["### Instruction:\n{{content}}\n### Response:"]),
    format_assistant=StringFormatter(slots=["\n", "{{content}}"]),
    format_separator=EmptyFormatter(slots=["\n", {"token": "<|EOT|>"}, "\n"]),
    default_system=(
        "You are an AI programming assistant, utilizing the Deepseek Coder model, "
        "developed by Deepseek Company, and you only answer questions related to computer science. "
        "For politically sensitive questions, security and privacy issues, "
        "and other non-computer science questions, you will refuse to answer\n"
    ),
    stop_words=["<|EOT|>"],
    efficient_eos=True,
)


_register_template(
    name="default",
    format_user=StringFormatter(slots=["Human: {{content}}\nAssistant: "]),
    format_system=StringFormatter(slots=["{{content}}\n"]),
    format_separator=EmptyFormatter(slots=["\n"]),
)


_register_template(
    name="falcon",
    format_user=StringFormatter(slots=["User: {{content}}\nFalcon:"]),
    format_separator=EmptyFormatter(slots=["\n"]),
    efficient_eos=True,
)


_register_template(
    name="intern",
    format_user=StringFormatter(slots=["<|User|>:{{content}}", {"token": "<eoh>"}, "\n<|Bot|>:"]),
    format_separator=EmptyFormatter(slots=[{"token": "<eoa>"}, "\n"]),
    stop_words=["<eoa>"],
    efficient_eos=True,
)


_register_template(
    name="intern2",
    format_user=StringFormatter(slots=["<|im_start|>user\n{{content}}<|im_end|>\n<|im_start|>assistant\n"]),
    format_system=StringFormatter(slots=[{"bos_token"}, "<|im_start|>system\n{{content}}<|im_end|>\n"]),
    format_separator=EmptyFormatter(slots=["\n"]),
    default_system=(
        "You are an AI assistant whose name is InternLM (书生·浦语).\n"
        "- InternLM (书生·浦语) is a conversational language model that is developed "
        "by Shanghai AI Laboratory (上海人工智能实验室). It is designed to be helpful, honest, and harmless.\n"
        "- InternLM (书生·浦语) can understand and communicate fluently in the language chosen "
        "by the user such as English and 中文."
    ),
    stop_words=["<|im_end|>"],
    efficient_eos=True,  # internlm2 tokenizer cannot set eos_token_id
)


_register_template(
    name="llama2",
    format_user=StringFormatter(slots=[{"bos_token"}, "[INST] {{content}} [/INST]"]),
    format_system=StringFormatter(slots=["<<SYS>>\n{{content}}\n<</SYS>>\n\n"]),
    default_system=(
        "You are a helpful, respectful and honest assistant. "
        "Always answer as helpfully as possible, while being safe. "
        "Your answers should not include any harmful, unethical, "
        "racist, sexist, toxic, dangerous, or illegal content. "
        "Please ensure that your responses are socially unbiased and positive in nature.\n\n"
        "If a question does not make any sense, or is not factually coherent, "
        "explain why instead of answering something not correct. "
        "If you don't know the answer to a question, please don't share false information."
    ),
)


_register_template(
    name="llama2_zh",
    format_user=StringFormatter(slots=[{"bos_token"}, "[INST] {{content}} [/INST]"]),
    format_system=StringFormatter(slots=["<<SYS>>\n{{content}}\n<</SYS>>\n\n"]),
    default_system="You are a helpful assistant. 你是一个乐于助人的助手。",
)


_register_template(
    name="mistral",
    format_user=StringFormatter(slots=["[INST] {{content}} [/INST]"]),
    format_system=StringFormatter(slots=[{"bos_token"}, "{{content}}"]),
    force_system=True,
)


_register_template(
    name="openchat",
    format_user=StringFormatter(slots=["GPT4 Correct User: {{content}}", {"eos_token"}, "GPT4 Correct Assistant:"]),
    format_assistant=StringFormatter(slots=["{{content}}"]),
    format_system=StringFormatter(slots=[{"bos_token"}, "{{content}}"]),
    force_system=True,
)


_register_template(
    name="orion",
    format_user=StringFormatter(slots=["Human: {{content}}\n\nAssistant: ", {"eos_token"}]),
    format_system=StringFormatter(slots=[{"bos_token"}, "{{content}}"]),
    force_system=True,
)


_register_template(
    name="qwen",
    format_user=StringFormatter(slots=["<|im_start|>user\n{{content}}<|im_end|>\n<|im_start|>assistant\n"]),
    format_system=StringFormatter(slots=["<|im_start|>system\n{{content}}<|im_end|>\n"]),
    format_separator=EmptyFormatter(slots=["\n"]),
    default_system="You are a helpful assistant.",
    stop_words=["<|im_end|>"],
    replace_eos=True,
)


_register_template(
    name="solar",
    format_user=StringFormatter(slots=["### User:\n{{content}}\n\n### Assistant:\n"]),
    format_system=StringFormatter(slots=["### System:\n{{content}}\n\n"]),
    efficient_eos=True,
)


_register_template(
    name="starchat",
    format_user=StringFormatter(
        slots=[{"token": "<|user|>"}, "\n{{content}}", {"token": "<|end|>"}, "\n", {"token": "<|assistant|>"}]
    ),
    format_system=StringFormatter(slots=[{"token": "<|system|>"}, "\n{{content}}", {"token": "<|end|>"}, "\n"]),
    format_separator=EmptyFormatter(slots=["\n"]),
    stop_words=["<|end|>"],
    replace_eos=True,
    force_system=True,
)


_register_template(
    name="vanilla",
)


_register_template(
    name="vicuna",
    format_user=StringFormatter(slots=["USER: {{content}} ASSISTANT:"]),
    default_system=(
        "A chat between a curious user and an artificial intelligence assistant. "
        "The assistant gives helpful, detailed, and polite answers to the user's questions."
    ),
)


_register_template(
    name="xuanyuan",
    format_user=StringFormatter(slots=["Human: {{content}} Assistant:"]),
    default_system=(
        "以下是用户和人工智能助手之间的对话。用户以Human开头，人工智能助手以Assistant开头，"
        "会对人类提出的问题给出有帮助、高质量、详细和礼貌的回答，并且总是拒绝参与与不道德、"
        "不安全、有争议、政治敏感等相关的话题、问题和指示。\n"
    ),
)


_register_template(
    name="xverse",
    format_user=StringFormatter(slots=["Human: {{content}}\n\nAssistant: "]),
)


_register_template(
    name="yayi",
    format_user=StringFormatter(slots=[{"token": "<|Human|>"}, ":\n{{content}}\n\n", {"token": "<|YaYi|>"}, ":"]),
    format_system=StringFormatter(slots=[{"token": "<|System|>"}, ":\n{{content}}\n\n"]),
    format_separator=EmptyFormatter(slots=["\n\n"]),
    default_system=(
        "You are a helpful, respectful and honest assistant named YaYi "
        "developed by Beijing Wenge Technology Co.,Ltd. "
        "Always answer as helpfully as possible, while being safe.  "
        "Your answers should not include any harmful, unethical, "
        "racist, sexist, toxic, dangerous, or illegal content. "
        "Please ensure that your responses are socially unbiased and positive in nature.\n\n"
        "If a question does not make any sense, or is not factually coherent, "
        "explain why instead of answering something not correct. "
        "If you don't know the answer to a question, please don't share false information."
    ),
    stop_words=["<|End|>"],
)


_register_template(
    name="yi",
    format_user=StringFormatter(slots=["<|im_start|>user\n{{content}}<|im_end|>\n<|im_start|>assistant\n"]),
    format_separator=EmptyFormatter(slots=["\n"]),
    stop_words=["<|im_end|>"],
    replace_eos=True,
)


_register_template(
    name="yuan",
    format_user=StringFormatter(slots=["{{content}}", {"token": "<sep>"}]),
    format_separator=EmptyFormatter(slots=["\n"]),
    stop_words=["<eod>"],
    replace_eos=True,
)


_register_template(
    name="zephyr",
    format_user=StringFormatter(slots=["<|user|>\n{{content}}", {"eos_token"}, "<|assistant|>"]),
    format_system=StringFormatter(slots=["<|system|>\n{{content}}", {"eos_token"}]),
    default_system="You are a friendly chatbot who always responds in the style of a pirate",
)


_register_template(
    name="ziya",
    format_user=StringFormatter(slots=[{"token": "<human>"}, ":{{content}}\n", {"token": "<bot>"}, ":"]),
    format_separator=EmptyFormatter(slots=["\n"]),
)
