from collections import namedtuple
import csv
import json
import os
import os.path as osp

from diffusers import DiffusionPipeline
import migraphx_diffusers
import torch


def parse_args():
    from argparse import ArgumentParser
    parser = ArgumentParser(description="SDXL inference with migraphx backend")

    #=========================== mdoel load and compile ========================
    parser.add_argument(
        "-m", 
        "--model-dir",
        type=str,
        required=True,
        help="Path to local model directory.",
    )
    parser.add_argument(
        "--force-compile",
        action="store_true",
        default=False,
        help="Ignore existing .mxr files and override them",
    )
    parser.add_argument(
        "--img-size",
        type=int,
        default=None,
        help="output image size",
    )
    parser.add_argument(
        "--num-images-per-prompt",
        type=int,
        default=1,
        help="The number of images to generate per prompt."
    )
    # --------------------------------------------------------------------------

    # =============================== generation ===============================
    parser.add_argument(
        "-p",
        "--parti-prompts-file",
        type=str,
        required=True,
        help="Number of iteration steps",
    )
    parser.add_argument(
        "-t",
        "--num-inference-steps",
        type=int,
        default=50,
        help="Number of iteration steps",
    )
    parser.add_argument(
        "--save-dir",
        type=str,
        default=None,
        help="Path to save images",
    )
    parser.add_argument(
        "-s",
        "--seed",
        type=int,
        default=42,
        help="Random seed",
    )
    parser.add_argument(
        "--resume",
        action="store_true",
        help="resume image generation",
    )
    # --------------------------------------------------------------------------

    args = parser.parse_args()
    return args


def get_name_and_migraphx_config(model_dir):
    model_index_json = osp.join(model_dir, "model_index.json")
    with open(model_index_json, "r") as f:
        pipe_cfg = json.load(f)
    
    if pipe_cfg["_class_name"] == "StableDiffusionXLPipeline":
        return 'sdxl', migraphx_diffusers.DEFAULT_ARGS['sdxl']
    elif pipe_cfg["_class_name"] == "StableDiffusionPipeline":
        return 'sd2.1', migraphx_diffusers.DEFAULT_ARGS['sd2.1']
    else:
        raise NotImplementedError(
            f"{pipe_cfg['_class_name']} has not been adapted yet")


def parse_prompts(parti_prompts_file):
    Prompt = namedtuple("Prompt", 
                        ["prompt_text", "category", "challenge", "note"])
    prompt_list = []

    with open(parti_prompts_file, "r") as f:
        csv_reader = csv.reader(f, delimiter="\t")
        for i, row in enumerate(csv_reader):
            if i == 0:
                continue
            prompt_list.append(Prompt(*row))
    
    return prompt_list


def main():
    args = parse_args()
    name, migraphx_config = get_name_and_migraphx_config(args.model_dir)

    if args.img_size is not None:
        migraphx_config['common_args']['img_size'] = args.img_size
    migraphx_config['common_args'].update(dict(
        batch=args.num_images_per_prompt,
        force_compile=args.force_compile,
    ))

    pipe = DiffusionPipeline.from_pretrained(
        args.model_dir,
        torch_dtype=torch.float16,
        migraphx_config=migraphx_config
    )
    pipe.to("cuda")

    os.makedirs(args.save_dir, exist_ok=True)
    generator = torch.Generator("cuda").manual_seed(args.seed)

    print("Generating image...")
    for i, prompt in enumerate(parse_prompts(args.parti_prompts_file)):
        sub_dir = osp.join(args.save_dir, 
                           prompt.category.replace(" ", "").replace("&", "_"),
                           f"prompt_{i:0>4d}")
        prompt_json = osp.join(sub_dir, "prompt_info.json")

        # =========================== resume =========================
        if args.resume:
            check_file_list = [osp.join(sub_dir, f"image_{j:0>2d}.png") 
                               for j in range(args.num_images_per_prompt)]
            check_file_list.append(prompt_json)
            if all([osp.exists(f) for f in check_file_list]):
                print(f"Skipping prompt {i}: \"{prompt.prompt_text}\"")
                continue
        
        # =========================== generate image =========================
        print(f"Processing prompt {i}: \"{prompt.prompt_text}\"")
        if not osp.isdir(sub_dir):
            os.makedirs(sub_dir, exist_ok=True)
        
        with open(prompt_json, "w") as f:
            json.dump(prompt._asdict(), f)

        images = pipe(
            prompt=prompt.prompt_text, 
            num_inference_steps=args.num_inference_steps,
            generator=generator
        ).images

        for j, image in enumerate(images):
            save_path = osp.join(sub_dir, f"{j:0>2d}.png")
            image.save(save_path)
            print(f"Generated image: {save_path}")


if __name__ == "__main__":
    main()