import re


def build_messages(sys, user, images, raw_res, num_docs=None, index=None, titles=None, instruction=None):
    messages = []
    user_list = []

    if sys is not None:
        messages.append({"role": "system", "content": sys})

    for segment in re.split("(<image>|<video>|<index>|<title>|<n_images>|<instruction>)", user):
        if segment == "<image>":
            image_dict = images.pop(0)
            user_list.append({"type": "image", 'image': image_dict.get('image'), 'bbox': image_dict.get('bbox', None), 'dynamic_crop': image_dict.get('dynamic_crop', False), 'max_pixels': image_dict.get('max_pixels', None)})
        elif segment == "<index>":
            user_list.append({"type": "text", "text": str(index)})
        elif segment == "<title>":
            title = titles.pop(0)
            user_list.append({"type": "text", "text": title})
        elif segment == "<n_images>":
            for i in range(num_docs):
                image_dict = images.pop(0)
                user_list.append({"type": "image", 'image': image_dict.get('image'), 'bbox': image_dict.get('bbox', None), 'dynamic_crop': image_dict.get('dynamic_crop', False), 'max_pixels': image_dict.get('max_pixels', None)})
        elif segment == "<instruction>":
            user_list.append({"type": "text", "text": instruction or ""})
        else:
            user_list.append({"type": "text", "text": segment})
    messages.append({"role": "user", "content": user_list})

    if raw_res is not None:
        messages.append({"role": "assistant", "content": [{'type': 'text', 'text': raw_res}]})

    return messages