#!/usr/bin/env python3

import argparse
import os
import sys
import importlib

from transformers import AutoTokenizer, AutoConfig, AutoModel
import torch

# Add parent directory to path for imports
sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..'))
from utils.common import save_output_data


def parse_arguments():
    parser = argparse.ArgumentParser(description='Run original embedding model')
    parser.add_argument(
        '--model-path',
        '-m',
        help='Path to the model'
    )
    parser.add_argument(
        '--prompts-file',
        '-p',
        help='Path to file containing prompts (one per line)'
    )
    parser.add_argument(
        '--use-sentence-transformers',
        action='store_true',
        help=('Use SentenceTransformer to apply all numbered layers '
              '(01_Pooling, 02_Dense, 03_Dense, 04_Normalize)')
    )
    parser.add_argument(
        '--device',
        '-d',
        help='Device to use (cpu, cuda, mps, auto)',
        default='auto'
    )
    return parser.parse_args()


def load_model_and_tokenizer(model_path, use_sentence_transformers=False, device="auto"):
    if device == "cpu":
        device_map = {"": "cpu"}
        print("Forcing CPU usage")
    elif device == "auto":
        # On Mac, "auto" device_map can cause issues with accelerate
        # So we detect the best device manually
        if torch.cuda.is_available():
            device_map = {"": "cuda"}
            print("Using CUDA")
        elif torch.backends.mps.is_available():
            device_map = {"": "mps"}
            print("Using MPS (Apple Metal)")
        else:
            device_map = {"": "cpu"}
            print("Using CPU")
    else:
        device_map = {"": device}

    if use_sentence_transformers:
        from sentence_transformers import SentenceTransformer
        print("Using SentenceTransformer to apply all numbered layers")
        model = SentenceTransformer(model_path)
        tokenizer = model.tokenizer
        config = model[0].auto_model.config  # ty: ignore[unresolved-attribute]
    else:
        tokenizer = AutoTokenizer.from_pretrained(model_path)
        config = AutoConfig.from_pretrained(model_path, trust_remote_code=True)

        # This can be used to override the sliding window size for manual testing. This
        # can be useful to verify the sliding window attention mask in the original model
        # and compare it with the converted .gguf model.
        if hasattr(config, 'sliding_window'):
            original_sliding_window = config.sliding_window
            print(f"Modified sliding window: {original_sliding_window} -> {config.sliding_window}")

        unreleased_model_name = os.getenv('UNRELEASED_MODEL_NAME')
        print(f"Using unreleased model: {unreleased_model_name}")
        if unreleased_model_name:
            model_name_lower = unreleased_model_name.lower()
            unreleased_module_path = f"transformers.models.{model_name_lower}.modular_{model_name_lower}"
            class_name = f"{unreleased_model_name}Model"
            print(f"Importing unreleased model module: {unreleased_module_path}")

            try:
                model_class = getattr(importlib.import_module(unreleased_module_path), class_name)
                model = model_class.from_pretrained(
                    model_path,
                    device_map=device_map,
                    offload_folder="offload",
                    trust_remote_code=True,
                    config=config
                )
            except (ImportError, AttributeError) as e:
                print(f"Failed to import or load model: {e}")
                sys.exit(1)
        else:
            model = AutoModel.from_pretrained(
                model_path,
                device_map=device_map,
                offload_folder="offload",
                trust_remote_code=True,
                config=config
            )
        print(f"Model class: {type(model)}")
        print(f"Model file: {type(model).__module__}")

        # Verify the model is using the correct sliding window
        if hasattr(model.config, 'sliding_window'):
            print(f"Model's sliding_window: {model.config.sliding_window}")
        else:
            print("Model config does not have sliding_window attribute")

    return model, tokenizer, config


def get_prompt(args):
    if args.prompts_file:
        try:
            with open(args.prompts_file, 'r', encoding='utf-8') as f:
                return f.read().strip()
        except FileNotFoundError:
            print(f"Error: Prompts file '{args.prompts_file}' not found")
            sys.exit(1)
        except Exception as e:
            print(f"Error reading prompts file: {e}")
            sys.exit(1)
    else:
        return "Hello world today"


def main():
    args = parse_arguments()

    model_path = os.environ.get('EMBEDDING_MODEL_PATH', args.model_path)
    if model_path is None:
        print("Error: Model path must be specified either via --model-path argument "
              "or EMBEDDING_MODEL_PATH environment variable")
        sys.exit(1)

    # Determine if we should use SentenceTransformer
    use_st = (
        args.use_sentence_transformers or os.environ.get('USE_SENTENCE_TRANSFORMERS', '').lower() in ('1', 'true', 'yes')
    )

    model, tokenizer, config = load_model_and_tokenizer(model_path, use_st, args.device)

    # Get the device the model is on
    if not use_st:
        device = next(model.parameters()).device
    else:
        # For SentenceTransformer, get device from the underlying model
        device = next(model[0].auto_model.parameters()).device

    model_name = os.path.basename(model_path)

    prompt_text = get_prompt(args)
    texts = [prompt_text]

    with torch.no_grad():
        if use_st:
            embeddings = model.encode(texts, convert_to_numpy=True)
            all_embeddings = embeddings  # Shape: [batch_size, hidden_size]

            encoded = tokenizer(
                texts,
                padding=True,
                truncation=True,
                return_tensors="pt"
            )
            tokens = encoded['input_ids'][0]
            token_ids = tokens.cpu().tolist()
            token_strings = tokenizer.convert_ids_to_tokens(tokens)
            for i, (token_id, token_str) in enumerate(zip(tokens, token_strings)):
                print(f"{token_id:6d} -> '{token_str}'")

            print(f"Embeddings shape (after all SentenceTransformer layers): {all_embeddings.shape}")
            print(f"Embedding dimension: {all_embeddings.shape[1] if len(all_embeddings.shape) > 1 else all_embeddings.shape[0]}")
        else:
            # Standard approach: use base model output only
            encoded = tokenizer(
                texts,
                padding=True,
                truncation=True,
                return_tensors="pt"
            )

            tokens = encoded['input_ids'][0]
            token_ids = tokens.cpu().tolist()
            token_strings = tokenizer.convert_ids_to_tokens(tokens)
            for i, (token_id, token_str) in enumerate(zip(tokens, token_strings)):
                print(f"{token_id:6d} -> '{token_str}'")

            # Move inputs to the same device as the model
            encoded = {k: v.to(device) for k, v in encoded.items()}
            outputs = model(**encoded)
            hidden_states = outputs.last_hidden_state  # Shape: [batch_size, seq_len, hidden_size]

            all_embeddings = hidden_states[0].float().cpu().numpy()  # Shape: [seq_len, hidden_size]

            print(f"Hidden states shape: {hidden_states.shape}")
            print(f"All embeddings shape: {all_embeddings.shape}")
            print(f"Embedding dimension: {all_embeddings.shape[1]}")

        if len(all_embeddings.shape) == 1:
            n_embd = all_embeddings.shape[0]
            n_embd_count = 1
            all_embeddings = all_embeddings.reshape(1, -1)
        else:
            n_embd = all_embeddings.shape[1]
            n_embd_count = all_embeddings.shape[0]

        print()

        for j in range(n_embd_count):
            embedding = all_embeddings[j]
            print(f"embedding {j}: ", end="")

            # Print first 3 values
            for i in range(min(3, n_embd)):
                print(f"{embedding[i]:9.6f} ", end="")

            print(" ... ", end="")

            # Print last 3 values
            for i in range(n_embd - 3, n_embd):
                print(f"{embedding[i]:9.6f} ", end="")

            print()  # New line

        print()

        flattened_embeddings = all_embeddings.flatten()
        print(f"Total values: {len(flattened_embeddings)} ({n_embd_count} embeddings × {n_embd} dimensions)")
        print("")

        save_output_data(flattened_embeddings, token_ids, prompt_text, model_name, type_suffix="-embeddings")


if __name__ == "__main__":
    main()
