#
# Copyright 2016 The BigDL Authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

import torch
import time
import argparse

from transformers import AutoModelForCausalLM, LlamaTokenizer
from ipex_llm import optimize_model

WIZARDCODERPYTHON_PROMPT_FORMAT = """Below is an instruction that describes a task. Write a response that appropriately completes the request.

### Instruction:
{prompt}

### Response:"""

if __name__ == '__main__':
    parser = argparse.ArgumentParser(description='Predict Tokens using `generate()` API for WizardCoder-Python model')
    parser.add_argument('--repo-id-or-model-path', type=str, default="WizardLM/WizardCoder-Python-7B-V1.0",
                        help='The huggingface repo id for the WizardCoder-Python (e.g. `WizardLM/WizardCoder-Python-7B-V1.0`) to be downloaded'
                             ', or the path to the huggingface checkpoint folder')
    parser.add_argument('--prompt', type=str, default="def print_hello_world():",
                        help='Prompt to infer')
    parser.add_argument('--n-predict', type=int, default=64,
                        help='Max tokens to predict')

    args = parser.parse_args()
    model_path = args.repo_id_or_model_path

    # Load model
    model = AutoModelForCausalLM.from_pretrained(model_path, trust_remote_code=True)

    # With only one line to enable IPEX-LLM optimization on model
    model = optimize_model(model)

    # Load tokenizer
    tokenizer = LlamaTokenizer.from_pretrained(model_path, trust_remote_code=True)

    # Generate predicted tokens
    with torch.inference_mode():
        prompt = WIZARDCODERPYTHON_PROMPT_FORMAT.format(prompt=args.prompt)
        input_ids = tokenizer.encode(prompt, return_tensors="pt")
        st = time.time()
        output = model.generate(input_ids,
                                max_new_tokens=args.n_predict)
        end = time.time()
        output_str = tokenizer.decode(output[0], skip_special_tokens=True)
        print(f'Inference time: {end-st} s')
        print('-'*20, 'Output', '-'*20)
        print(output_str)