import os
from pathlib import Path
import spaces
import gradio as gr
from huggingface_hub import InferenceClient
from torch import nn
from transformers import AutoModel, AutoProcessor, AutoTokenizer, PreTrainedTokenizer, PreTrainedTokenizerFast, AutoModelForCausalLM, BitsAndBytesConfig
import torch
import torch.amp.autocast_mode
from PIL import Image
import torchvision.transforms.functional as TVF
import gc
from peft import PeftConfig

# Define the base directory
BASE_DIR = Path(__file__).resolve().parent

device = "cuda" if torch.cuda.is_available() else "cpu"
HF_TOKEN = os.environ.get("HF_TOKEN", None)
use_inference_client = False

llm_models = {
    "bunnycore/LLama-3.1-8B-Matrix": None,
    "Sao10K/Llama-3.1-8B-Stheno-v3.4": None,
    "unsloth/Meta-Llama-3.1-8B-bnb-4bit": None,
    "DevQuasar/HermesNova-Llama-3.1-8B": None,
    "mergekit-community/L3.1-Boshima-b-FIX": None,
    "meta-llama/Meta-Llama-3.1-8B": None, # gated
}

CLIP_PATH = "google/siglip-so400m-patch14-384"
MODEL_PATH = list(llm_models.keys())[0]
CHECKPOINT_PATH = BASE_DIR / "9em124t2-499968"
LORA_PATH = CHECKPOINT_PATH / "text_model"

JC_TITLE_MD = "<h1><center>JoyCaption Alpha One Mod</center></h1>"
JC_DESC_MD = """This space is mod of [fancyfeast/joy-caption-alpha-one](https://huggingface.co/spaces/fancyfeast/joy-caption-alpha-one),
 [Wi-zz/joy-caption-pre-alpha](https://huggingface.co/Wi-zz/joy-caption-pre-alpha)"""

CAPTION_TYPE_MAP = {
    ("descriptive", "formal", False, False): ["Write a descriptive caption for this image in a formal tone."],
    ("descriptive", "formal", False, True): ["Write a descriptive caption for this image in a formal tone within {word_count} words."],
    ("descriptive", "formal", True, False): ["Write a {length} descriptive caption for this image in a formal tone."],
    ("descriptive", "informal", False, False): ["Write a descriptive caption for this image in a casual tone."],
    ("descriptive", "informal", False, True): ["Write a descriptive caption for this image in a casual tone within {word_count} words."],
    ("descriptive", "informal", True, False): ["Write a {length} descriptive caption for this image in a casual tone."],
    ("training_prompt", "formal", False, False): ["Write a stable diffusion prompt for this image."],
    ("training_prompt", "formal", False, True): ["Write a stable diffusion prompt for this image within {word_count} words."],
    ("training_prompt", "formal", True, False): ["Write a {length} stable diffusion prompt for this image."],
    ("rng-tags", "formal", False, False): ["Write a list of Booru tags for this image."],
    ("rng-tags", "formal", False, True): ["Write a list of Booru tags for this image within {word_count} words."],
    ("rng-tags", "formal", True, False): ["Write a {length} list of Booru tags for this image."],
}

class ImageAdapter(nn.Module):
    def __init__(self, input_features: int, output_features: int, ln1: bool, pos_emb: bool, num_image_tokens: int, deep_extract: bool):
        super().__init__()
        self.deep_extract = deep_extract

        if self.deep_extract:
            input_features = input_features * 5

        self.linear1 = nn.Linear(input_features, output_features)
        self.activation = nn.GELU()
        self.linear2 = nn.Linear(output_features, output_features)
        self.ln1 = nn.Identity() if not ln1 else nn.LayerNorm(input_features)
        self.pos_emb = None if not pos_emb else nn.Parameter(torch.zeros(num_image_tokens, input_features))

        self.other_tokens = nn.Embedding(3, output_features)
        self.other_tokens.weight.data.normal_(mean=0.0, std=0.02)

    def forward(self, vision_outputs: torch.Tensor):
        if self.deep_extract:
            x = torch.concat((
                vision_outputs[-2],
                vision_outputs[3],
                vision_outputs[7],
                vision_outputs[13],
                vision_outputs[20],
            ), dim=-1)
            assert len(x.shape) == 3, f"Expected 3, got {len(x.shape)}"
            assert x.shape[-1] == vision_outputs[-2].shape[-1] * 5, f"Expected {vision_outputs[-2].shape[-1] * 5}, got {x.shape[-1]}"
        else:
            x = vision_outputs[-2]

        x = self.ln1(x)

        if self.pos_emb is not None:
            assert x.shape[-2:] == self.pos_emb.shape, f"Expected {self.pos_emb.shape}, got {x.shape[-2:]}"
            x = x + self.pos_emb

        x = self.linear1(x)
        x = self.activation(x)
        x = self.linear2(x)

        other_tokens = self.other_tokens(torch.tensor([0, 1], device=self.other_tokens.weight.device).expand(x.shape[0], -1))
        assert other_tokens.shape == (x.shape[0], 2, x.shape[2]), f"Expected {(x.shape[0], 2, x.shape[2])}, got {other_tokens.shape}"
        x = torch.cat((other_tokens[:, 0:1], x, other_tokens[:, 1:2]), dim=1)

        return x

    def get_eot_embedding(self):
        return self.other_tokens(torch.tensor([2], device=self.other_tokens.weight.device)).squeeze(0)

tokenizer = None
text_model_client = None
text_model = None
image_adapter = None
peft_config = None

def load_text_model(model_name: str=MODEL_PATH, gguf_file: str | None=None, is_nf4: bool=True):
    global tokenizer, text_model, image_adapter, peft_config, text_model_client, use_inference_client
    try:
        nf4_config = BitsAndBytesConfig(load_in_4bit=True, bnb_4bit_quant_type="nf4",
                                        bnb_4bit_use_double_quant=True, bnb_4bit_compute_dtype=torch.bfloat16)
        print("Loading tokenizer")
        if gguf_file:
            tokenizer = AutoTokenizer.from_pretrained(model_name, gguf_file=gguf_file, use_fast=True, legacy=False)
        else:
            tokenizer = AutoTokenizer.from_pretrained(model_name, use_fast=False, legacy=False)
        assert isinstance(tokenizer, PreTrainedTokenizer) or isinstance(tokenizer, PreTrainedTokenizerFast), f"Tokenizer is of type {type(tokenizer)}"
        
        print(f"Loading LLM: {model_name}")
        if gguf_file:
            if device == "cpu":
                text_model = AutoModelForCausalLM.from_pretrained(model_name, gguf_file=gguf_file, device_map=device, torch_dtype=torch.bfloat16).eval()
            elif is_nf4:
                text_model = AutoModelForCausalLM.from_pretrained(model_name, quantization_config=nf4_config, device_map=device, torch_dtype=torch.bfloat16).eval()
            else:
                text_model = AutoModelForCausalLM.from_pretrained(model_name, device_map=device, torch_dtype=torch.bfloat16).eval()
        else:
            if device == "cpu":
                text_model = AutoModelForCausalLM.from_pretrained(model_name, device_map=device, torch_dtype=torch.bfloat16).eval()
            elif is_nf4:
                text_model = AutoModelForCausalLM.from_pretrained(model_name, quantization_config=nf4_config, device_map=device, torch_dtype=torch.bfloat16).eval()
            else:
                text_model = AutoModelForCausalLM.from_pretrained(model_name, device_map=device, torch_dtype=torch.bfloat16).eval()
        
        if LORA_PATH.exists():
            print("Loading VLM's custom text model")
            if is_nf4:
                peft_config = PeftConfig.from_pretrained(str(LORA_PATH), device_map=device, quantization_config=nf4_config)
            else:
                peft_config = PeftConfig.from_pretrained(str(LORA_PATH), device_map=device)
            text_model.add_adapter(peft_config)
            text_model.enable_adapters()
        
        print("Loading image adapter")
        image_adapter = ImageAdapter(clip_model.config.hidden_size, text_model.config.hidden_size, False, False, 38, False).eval().to("cpu")
        image_adapter_path = CHECKPOINT_PATH / "image_adapter.pt"
        image_adapter.load_state_dict(torch.load(image_adapter_path, map_location="cpu", weights_only=True))
        image_adapter.eval().to(device)
    except Exception as e:
        print(f"LLM load error: {e}")
        raise Exception(f"LLM load error: {e}") from e
    finally:
        torch.cuda.empty_cache()
        gc.collect()

load_text_model.zerogpu = True

# Load CLIP
print("Loading CLIP")
clip_processor = AutoProcessor.from_pretrained(CLIP_PATH)
clip_model = AutoModel.from_pretrained(CLIP_PATH).vision_model

clip_model_path = CHECKPOINT_PATH / "clip_model.pt"
if clip_model_path.exists():
    print("Loading VLM's custom vision model")
    checkpoint = torch.load(clip_model_path, map_location='cpu')
    checkpoint = {k.replace("_orig_mod.module.", ""): v for k, v in checkpoint.items()}
    clip_model.load_state_dict(checkpoint)
    del checkpoint

clip_model.eval().requires_grad_(False).to(device)

# Load text model
load_text_model()

@spaces.GPU()
@torch.no_grad()
def stream_chat_mod(input_image: Image.Image, caption_type: str, caption_tone: str, caption_length: str | int, max_new_tokens: int=300, top_p: float=0.9, temperature: float=0.6, progress=gr.Progress(track_tqdm=True)) -> str:
    global use_inference_client
    global text_model
    torch.cuda.empty_cache()
    gc.collect()

    length = None if caption_length == "any" else caption_length

    if isinstance(length, str):
        try:
            length = int(length)
        except ValueError:
            pass

    if caption_type == "rng-tags" or caption_type == "training_prompt":
        caption_tone = "formal"

    prompt_key = (caption_type, caption_tone, isinstance(length, str), isinstance(length, int))
    if prompt_key not in CAPTION_TYPE_MAP:
        raise ValueError(f"Invalid caption type: {prompt_key}")

    prompt_str = CAPTION_TYPE_MAP[prompt_key][0].format(length=length, word_count=length)
    print(f"Prompt: {prompt_str}")

    image = input_image.resize((384, 384), Image.LANCZOS)
    pixel_values = TVF.pil_to_tensor(image).unsqueeze(0) / 255.0
    pixel_values = TVF.normalize(pixel_values, [0.5], [0.5])
    pixel_values = pixel_values.to(device)

    prompt = tokenizer.encode(prompt_str, return_tensors='pt', padding=False, truncation=False, add_special_tokens=False)

    with torch.amp.autocast_mode.autocast(device, enabled=True):
        vision_outputs = clip_model(pixel_values=pixel_values, output_hidden_states=True)
        image_features = vision_outputs.hidden_states
        embedded_images = image_adapter(image_features)
        embedded_images = embedded_images.to(device)
    
    prompt_embeds = text_model.model.embed_tokens(prompt.to(device))
    assert prompt_embeds.shape == (1, prompt.shape[1], text_model.config.hidden_size), f"Prompt shape is {prompt_embeds.shape}, expected {(1, prompt.shape[1], text_model.config.hidden_size)}"
    embedded_bos = text_model.model.embed_tokens(torch.tensor([[tokenizer.bos_token_id]], device=text_model.device, dtype=torch.int64))
    eot_embed = image_adapter.get_eot_embedding().unsqueeze(0).to(dtype=text_model.dtype)

    inputs_embeds = torch.cat([
        embedded_bos.expand(embedded_images.shape[0], -1, -1),
        embedded_images.to(dtype=embedded_bos.dtype),
        prompt_embeds.expand(embedded_images.shape[0], -1, -1),
        eot_embed.expand(embedded_images.shape[0], -1, -1),
    ], dim=1)

    input_ids = torch.cat([
        torch.tensor([[tokenizer.bos_token_id]], dtype=torch.long),
        torch.zeros((1, embedded_images.shape[1]), dtype=torch.long),
        prompt,
        torch.tensor([[tokenizer.convert_tokens_to_ids("<|eot_id|>")]], dtype=torch.long),
    ], dim=1).to(device)
    attention_mask = torch.ones_like(input_ids)

    text_model.to(device)
    generate_ids = text_model.generate(input_ids, inputs_embeds=inputs_embeds, attention_mask=attention_mask, max_new_tokens=max_new_tokens,
                                       do_sample=True, suppress_tokens=None, top_p=top_p, temperature=temperature)

    generate_ids = generate_ids[:, input_ids.shape[1]:]
    if generate_ids[0][-1] == tokenizer.eos_token_id or generate_ids[0][-1] == tokenizer.convert_tokens_to_ids("<|eot_id|>"):
        generate_ids = generate_ids[:, :-1]

    caption = tokenizer.batch_decode(generate_ids, skip_special_tokens=False, clean_up_tokenization_spaces=False)[0]

    return caption.strip()

def is_repo_name(s):
    import re
    return re.fullmatch(r'^[^/,\s\"\']+/[^/,\s\"\']+$', s)

def is_repo_exists(repo_id):
    from huggingface_hub import HfApi
    try:
        api = HfApi(token=HF_TOKEN)
        return api.repo_exists(repo_id=repo_id)
    except Exception as e:
        print(f"Error: Failed to connect {repo_id}.")
        print(e)
        return True  # for safety

def get_text_model():
    return list(llm_models.keys())

def is_gguf_repo(repo_id: str):
    from huggingface_hub import HfApi
    try:
        api = HfApi(token=HF_TOKEN)
        if not is_repo_name(repo_id) or not is_repo_exists(repo_id):
            return False
        files = api.list_repo_files(repo_id=repo_id)
    except Exception as e:
        print(f"Error: Failed to get {repo_id}'s info.")
        print(e)
        gr.Warning(f"Error: Failed to get {repo_id}'s info.")
        return False
    files = [f for f in files if f.endswith(".gguf")]
    return len(files) > 0

def get_repo_gguf(repo_id: str):
    from huggingface_hub import HfApi
    try:
        api = HfApi(token=HF_TOKEN)
        if not is_repo_name(repo_id) or not is_repo_exists(repo_id):
            return gr.update(value="", choices=[])
        files = api.list_repo_files(repo_id=repo_id)
    except Exception as e:
        print(f"Error: Failed to get {repo_id}'s info.")
        print(e)
        gr.Warning(f"Error: Failed to get {repo_id}'s info.")
        return gr.update(value="", choices=[])
    files = [f for f in files if f.endswith(".gguf")]
    if len(files) == 0:
        return gr.update(value="", choices=[])
    else:
        return gr.update(value=files[0], choices=files)

@spaces.GPU()
def change_text_model(model_name: str=MODEL_PATH, use_client: bool=False, gguf_file: str | None=None,
                      is_nf4: bool=True, progress=gr.Progress(track_tqdm=True)):
    global use_inference_client, llm_models
    use_inference_client = use_client
    try:
        if not is_repo_name(model_name) or not is_repo_exists(model_name):
            raise gr.Error(f"Repo doesn't exist: {model_name}")
        if not gguf_file and is_gguf_repo(model_name):
            gr.Info(f"Please select a gguf file.")
            return gr.update(visible=True)
        if not use_inference_client:
            load_text_model(model_name, gguf_file, is_nf4)
        if model_name not in llm_models:
            llm_models[model_name] = gguf_file if gguf_file else None
        return gr.update(choices=get_text_model())
    except Exception as e:
        raise gr.Error(f"Model load error: {model_name}, {e}")

# Custom CSS for neon purple theme
css = """
body {
    background: linear-gradient(45deg, #1a0033, #4d0099);
    color: #e6ccff;
    font-family: 'Arial', sans-serif;
}
.gradio-container {
    max-width: 1200px !important;
    margin: auto;
}
.gr-button {
    background: linear-gradient(90deg, #8a2be2, #9400d3) !important;
    border: none !important;
    color: white !important;
    font-weight: bold;
    transition: all 0.3s ease;
}
.gr-button:hover {
    background: linear-gradient(90deg, #9400d3, #8a2be2) !important;
    box-shadow: 0 0 15px #9400d3;
}
.gr-form {
    border-radius: 15px;
    padding: 20px;
    background-color: rgba(60, 19, 97, 0.7) !important;
    box-shadow: 0 0 20px rgba(138, 43, 226, 0.4);
    backdrop-filter: blur(10px);
}
.gr-box {
    border-radius: 15px;
    background-color: rgba(75, 0, 130, 0.7) !important;
    box-shadow: 0 0 20px rgba(138, 43, 226, 0.4);
    backdrop-filter: blur(5px);
}
.gr-padded {
    padding: 20px;
}
.gr-form label, .gr-form .label-wrap {
    color: #e6ccff !important;
    font-weight: bold;
}
.gr-input, .gr-dropdown {
    background-color: rgba(47, 1, 71, 0.8) !important;
    border: 2px solid #8a2be2 !important;
    color: #ffffff !important;
    border-radius: 8px;
}
.gr-input::placeholder {
    color: #b19cd9 !important;
}
.gr-checkbox {
    background-color: #4b0082 !important;
    border-color: #8a2be2 !important;
}
.gr-checkbox:checked {
    background-color: #8a2be2 !important;
}
h1, h2, h3 {
    color: #ffd700 !important;
    text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);
}
.gr-block {
    border: none !important;
}
.gr-accordion {
    border: 2px solid #8a2be2;
    border-radius: 10px;
    overflow: hidden;
}
.gr-accordion summary {
    background-color: rgba(75, 0, 130, 0.9);
    color: #ffd700;
    padding: 10px;
    font-weight: bold;
    cursor: pointer;
}
"""

# Gradio interface
with gr.Blocks(css=css, theme=gr.themes.Soft()) as demo:
    gr.HTML(
        "<h1 style='text-align: center; color: #FFD700; text-shadow: 0 0 10px rgba(255, 215, 0, 0.5);'>JoyCaption Alpha One Mod</h1>"
        "<p style='text-align: center; color: #e6ccff;'>Generate captivating captions for your images!</p>"
    )
    with gr.Row():
        with gr.Column(scale=1):
            with gr.Group():
                jc_input_image = gr.Image(type="pil", label="Input Image", sources=["upload", "clipboard"], height=384)
                with gr.Row():
                    jc_caption_type = gr.Dropdown(
                        choices=["descriptive", "training_prompt", "rng-tags"],
                        label="Caption Type",
                        value="descriptive",
                    )
                    jc_caption_tone = gr.Dropdown(
                        choices=["formal", "informal"],
                        label="Caption Tone",
                        value="formal",
                    )
                    jc_caption_length = gr.Dropdown(
                        choices=["any", "very short", "short", "medium-length", "long", "very long"] +
                                [str(i) for i in range(20, 261, 10)],
                        label="Caption Length",
                        value="any",
                    )
                gr.Markdown("**Note:** Caption tone doesn't affect `rng-tags` and `training_prompt`.")
                with gr.Accordion("Advanced Settings", open=False):
                    with gr.Row():
                        jc_text_model = gr.Dropdown(label="LLM Model", info="You can enter a Hugging Face model repo_id to use.",
                                                    choices=get_text_model(), value=get_text_model()[0],
                                                    allow_custom_value=True, interactive=True, min_width=320)
                        jc_gguf = gr.Dropdown(label=f"GGUF Filename", choices=[], value="",
                                              allow_custom_value=True, min_width=320, visible=False)
                        jc_nf4 = gr.Checkbox(label="Use NF4 quantization", value=True)
                        jc_text_model_button = gr.Button("Load Model", variant="secondary")
                    jc_use_inference_client = gr.Checkbox(label="Use Inference Client", value=False, visible=False)
                    with gr.Row():
                        jc_tokens = gr.Slider(minimum=1, maximum=4096, value=300, step=1, label="Max tokens")
                        jc_temperature = gr.Slider(minimum=0.1, maximum=4.0, value=0.6, step=0.1, label="Temperature")
                        jc_topp = gr.Slider(minimum=0, maximum=2.0, value=0.9, step=0.01, label="Top-P")
            jc_run_button = gr.Button("Generate Caption", variant="primary")

        with gr.Column(scale=1):
            jc_output_caption = gr.Textbox(label="Generated Caption", show_copy_button=True)
    
    gr.Markdown(JC_DESC_MD)
    with gr.Row():
        gr.LoginButton()
        gr.DuplicateButton(value="Duplicate Space for private use", variant="secondary")

    jc_run_button.click(fn=stream_chat_mod, inputs=[jc_input_image, jc_caption_type, jc_caption_tone, jc_caption_length, jc_tokens, jc_topp, jc_temperature], outputs=[jc_output_caption])
    jc_text_model_button.click(change_text_model, inputs=[jc_text_model, jc_use_inference_client, jc_gguf, jc_nf4], outputs=[jc_text_model])
    jc_use_inference_client.change(change_text_model, inputs=[jc_text_model, jc_use_inference_client], outputs=[jc_text_model])

if __name__ == "__main__":
    demo.launch(share=True)