import base64
import dataclasses
import re
from enum import Enum, auto
from io import BytesIO
from typing import Any, Dict, List, Tuple, Union

from PIL import Image


class SeparatorStyle(Enum):
    """Different separator style."""

    SINGLE = auto()
    TWO = auto()
    PLAIN = auto()
    CHATML = auto()
    QWEN = auto()


@dataclasses.dataclass
class Conversation:
    """A class that keeps all conversation history."""

    system: str
    roles: List[str]
    messages: List[List[str]]
    offset: int
    sep_style: SeparatorStyle = SeparatorStyle.SINGLE
    sep: str = "###"
    sep2: str = None
    version: str = "Unknown"

    tokenizer_id: str = ""
    tokenizer: Any = None
    # Stop criteria (the default one is EOS token)
    stop_str: Union[str, List[str]] = None
    # Stops generation if meeting any token in this list
    stop_token_ids: List[int] = None

    skip_next: bool = False

    def get_prompt(self):
        messages = self.messages
        if len(messages) > 0 and type(messages[0][1]) is tuple:
            messages = self.messages.copy()
            init_role, init_msg = messages[0].copy()
            init_msg = init_msg[0]
            if "mmtag" in self.version:
                init_msg = init_msg.replace("<image>", "").strip()
                messages[0] = (init_role, init_msg)
                messages.insert(0, (self.roles[0], "<Image><image></Image>"))
                messages.insert(1, (self.roles[1], "Received."))
            elif not init_msg.startswith("<image>"):
                init_msg = init_msg.replace("<image>", "").strip()
                messages[0] = (init_role, "<image>\n" + init_msg)
            else:
                messages[0] = (init_role, init_msg)

        if self.sep_style == SeparatorStyle.SINGLE:
            ret = self.system + self.sep
            for role, message in messages:
                if message:
                    if type(message) is tuple:
                        message, _, _ = message
                    ret += role + ": " + message + self.sep
                else:
                    ret += role + ":"

        elif self.sep_style == SeparatorStyle.TWO:
            seps = [self.sep, self.sep2]
            ret = self.system + seps[0]
            for i, (role, message) in enumerate(messages):
                if message:
                    if type(message) is tuple:
                        message, _, _ = message
                    ret += role + ": " + message + seps[i % 2]
                else:
                    ret += role + ":"

        elif self.sep_style == SeparatorStyle.CHATML:
            ret = "" if self.system == "" else self.system + self.sep + "\n"
            for role, message in messages:
                if message:
                    if type(message) is tuple:
                        message, images, _ = message
                        message = "<image>" * len(images) + message
                    ret += role + "\n" + message + self.sep + "\n"
                else:
                    ret += role + "\n"
            return ret

        elif self.sep_style == SeparatorStyle.PLAIN:
            seps = [self.sep, self.sep2]
            ret = self.system
            for i, (role, message) in enumerate(messages):
                if message:
                    if type(message) is tuple:
                        message, _, _ = message
                    ret += message + seps[i % 2]
                else:
                    ret += ""
        else:
            raise ValueError(f"Invalid style: {self.sep_style}")

        return ret

    def append_message(self, role, message):
        self.messages.append([role, message])

    def process_image(self, image, image_process_mode, return_pil=False, image_format="PNG"):
        if image_process_mode == "Pad":

            def expand2square(pil_img, background_color=(122, 116, 104)):
                width, height = pil_img.size
                if width == height:
                    return pil_img
                elif width > height:
                    result = Image.new(pil_img.mode, (width, width), background_color)
                    result.paste(pil_img, (0, (width - height) // 2))
                    return result
                else:
                    result = Image.new(pil_img.mode, (height, height), background_color)
                    result.paste(pil_img, ((height - width) // 2, 0))
                    return result

            image = expand2square(image)
        elif image_process_mode in ["Default", "Crop"]:
            pass
        elif image_process_mode == "Resize":
            image = image.resize((336, 336))
        else:
            raise ValueError(f"Invalid image_process_mode: {image_process_mode}")

        if type(image) is not Image.Image:
            image = Image.open(image).convert("RGB")

        max_hw, min_hw = max(image.size), min(image.size)
        aspect_ratio = max_hw / min_hw
        max_len, min_len = 672, 448
        shortest_edge = int(min(max_len / aspect_ratio, min_len, min_hw))
        longest_edge = int(shortest_edge * aspect_ratio)
        W, H = image.size
        if H > W:
            H, W = longest_edge, shortest_edge
        else:
            H, W = shortest_edge, longest_edge
        image = image.resize((W, H))
        if return_pil:
            return image
        else:
            buffered = BytesIO()
            image.save(buffered, format=image_format)
            img_b64_str = base64.b64encode(buffered.getvalue()).decode()
            return img_b64_str

    def get_images(self, return_pil=False, return_path=False):
        images = []
        for i, (role, msg) in enumerate(self.messages[self.offset :]):
            if i % 2 == 0:
                if type(msg) is tuple:
                    msg, image, image_process_mode = msg
                    if type(image) != list:
                        image = [image]
                    for img in image:
                        if not return_path and self.is_image_file(img):
                            img = self.process_image(img, image_process_mode, return_pil=return_pil)
                        else:
                            images.append(img)
        return images

    def is_image_file(self, filename):
        image_extensions = [".png", ".jpg", ".jpeg", ".gif", ".bmp", ".tiff", ".webp"]
        return any(filename.lower().endswith(ext) for ext in image_extensions)

    def is_video_file(self, filename):
        video_extensions = [".mp4", ".mov", ".avi", ".mkv", ".wmv", ".flv", ".mpeg", ".mpg"]
        return any(filename.lower().endswith(ext) for ext in video_extensions)

    def to_gradio_chatbot(self):
        ret = []
        for i, (role, msg) in enumerate(self.messages[self.offset :]):
            if i % 2 == 0:
                if type(msg) is tuple:
                    msg, image, image_process_mode = msg
                    if type(image) != list:
                        image = [image]
                    if len(image) == 1:
                        msg = "<image>\n" + msg.replace("<image>", "").strip()
                    else:
                        msg = re.sub(r"(<image>)\n(?=<image>)", r"\1 ", msg)

                    img_str_list = []                         
                    for img in image:
                        if self.is_image_file(img):
                            img_b64_str = self.process_image(img, "Default", return_pil=False, image_format="JPEG")
                            img_str = f'<img src="data:image/jpeg;base64,{img_b64_str}" style="max-width: 256px; max-height: 256px; width: auto; height: auto; object-fit: contain;"/>'
                            img_str_list.append(img_str)
                        elif self.is_video_file(img):
                            ret.append(((img,), None))

                    msg = msg.strip()
                    img_place_holder = ""
                    for img_str in img_str_list:
                        img_place_holder += f"{img_str}\n\n"

                    if len(img_str_list) > 0:
                        msg = f"{img_place_holder}\n\n{msg}"

                    if len(msg) > 0:
                        ret.append([msg, None])
                else:
                    ret.append([msg, None])
            else:
                ret[-1][-1] = msg
        return ret

    def copy(self):
        return Conversation(system=self.system, roles=self.roles, messages=[[x, y] for x, y in self.messages], offset=self.offset, sep_style=self.sep_style, sep=self.sep, sep2=self.sep2, version=self.version)

    def dict(self):
        if len(self.get_images()) > 0:
            return {
                "system": self.system,
                "roles": self.roles,
                "messages": [[x, y[0] if type(y) is tuple else y] for x, y in self.messages],
                "offset": self.offset,
                "sep": self.sep,
                "sep2": self.sep2,
            }
        return {
            "system": self.system,
            "roles": self.roles,
            "messages": self.messages,
            "offset": self.offset,
            "sep": self.sep,
            "sep2": self.sep2,
        }


conv_vicuna_v0 = Conversation(
    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.",
    roles=("Human", "Assistant"),
    messages=[
        ["Human", "What are the key differences between renewable and non-renewable energy sources?"],
        [
            "Assistant",
            "Renewable energy sources are those that can be replenished naturally in a relatively "
            "short amount of time, such as solar, wind, hydro, geothermal, and biomass. "
            "Non-renewable energy sources, on the other hand, are finite and will eventually be "
            "depleted, such as coal, oil, and natural gas. Here are some key differences between "
            "renewable and non-renewable energy sources:\n"
            "1. Availability: Renewable energy sources are virtually inexhaustible, while non-renewable "
            "energy sources are finite and will eventually run out.\n"
            "2. Environmental impact: Renewable energy sources have a much lower environmental impact "
            "than non-renewable sources, which can lead to air and water pollution, greenhouse gas emissions, "
            "and other negative effects.\n"
            "3. Cost: Renewable energy sources can be more expensive to initially set up, but they typically "
            "have lower operational costs than non-renewable sources.\n"
            "4. Reliability: Renewable energy sources are often more reliable and can be used in more remote "
            "locations than non-renewable sources.\n"
            "5. Flexibility: Renewable energy sources are often more flexible and can be adapted to different "
            "situations and needs, while non-renewable sources are more rigid and inflexible.\n"
            "6. Sustainability: Renewable energy sources are more sustainable over the long term, while "
            "non-renewable sources are not, and their depletion can lead to economic and social instability.\n",
        ],
    ],
    offset=2,
    sep_style=SeparatorStyle.SINGLE,
    sep="###",
)


conv_qwen = Conversation(
    system="""<|im_start|>system
You are a helpful assistant.""",
    roles=("<|im_start|>user", "<|im_start|>assistant"),
    version="qwen",
    messages=[],
    offset=0,
    sep_style=SeparatorStyle.CHATML,
    sep="<|im_end|>",
)


default_conversation = conv_vicuna_v0
conv_templates = {
    "default": conv_vicuna_v0,
    "v0": conv_vicuna_v0,
    "qwen_1_5": conv_qwen,
    "qwen_2": conv_qwen,
}


if __name__ == "__main__":
    print(default_conversation.get_prompt())