# SPDX-License-Identifier: Apache-2.0

from __future__ import annotations

import json
import re
from typing import Any

import jsonschema
import pytest

from vllm.entrypoints.llm import LLM
from vllm.outputs import RequestOutput
from vllm.sampling_params import GuidedDecodingParams, SamplingParams

GUIDED_DECODING_BACKENDS_V1 = ["xgrammar", "guidance"]
MODELS_TO_TEST = [
    "Qwen/Qwen2.5-1.5B-Instruct", "mistralai/Ministral-8B-Instruct-2410"
]


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_json_completion(
    monkeypatch: pytest.MonkeyPatch,
    sample_json_schema: dict[str, Any],
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=1.0,
        max_tokens=1000,
        guided_decoding=GuidedDecodingParams(json=sample_json_schema))
    outputs = llm.generate(prompts=[
        f"Give an example JSON for an employee profile "
        f"that fits this schema: {sample_json_schema}"
    ] * 2,
                           sampling_params=sampling_params,
                           use_tqdm=True)

    assert outputs is not None

    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)
        prompt = output.prompt

        generated_text = output.outputs[0].text
        assert generated_text is not None
        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")
        output_json = json.loads(generated_text)
        jsonschema.validate(instance=output_json, schema=sample_json_schema)


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_json_completion_disable_any_whitespace(
    monkeypatch: pytest.MonkeyPatch,
    sample_json_schema: dict[str, Any],
    guided_decoding_backend: str,
    model_name: str,
):
    if guided_decoding_backend != "xgrammar":
        pytest.skip("disable-any-whitespace is only supported for xgrammar.")
    guided_decoding_backend = 'xgrammar:disable-any-whitespace'

    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=1.0,
        max_tokens=1000,
        guided_decoding=GuidedDecodingParams(json=sample_json_schema))
    outputs = llm.generate(prompts=[
        f"Give an example JSON for an employee profile "
        f"that fits this schema: {sample_json_schema}"
    ] * 2,
                           sampling_params=sampling_params,
                           use_tqdm=True)

    assert outputs is not None

    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)
        prompt = output.prompt

        generated_text = output.outputs[0].text
        assert generated_text is not None
        assert "\n" not in generated_text
        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")
        output_json = json.loads(generated_text)
        jsonschema.validate(instance=output_json, schema=sample_json_schema)


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_json_object(
    monkeypatch: pytest.MonkeyPatch,
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=1.0,
        max_tokens=100,
        n=2,
        guided_decoding=GuidedDecodingParams(json_object=True))

    outputs = llm.generate(
        prompts=("Generate a JSON object with curly braces for a person with "
                 "name and age fields for John Smith who is 31 years old."),
        sampling_params=sampling_params,
        use_tqdm=True)

    assert outputs is not None
    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)

        for i in range(2):
            generated_text = output.outputs[i].text
            print(generated_text)
            assert generated_text is not None

            # Parse to verify it is valid JSON
            parsed_json = json.loads(generated_text)
            allowed_types: tuple[type, ...] = (dict, )
            if guided_decoding_backend == "xgrammar":
                # TODO - we are currently too permissive with xgrammar and
                # allow # any valid json (typically comes back as a list or
                # object).  We can fix this by specifying a jsonschema of
                # {"type": "object"}, # but we need this fix in a release
                # first: https://github.com/mlc-ai/xgrammar/pull/264
                allowed_types = (dict, list)
            assert isinstance(parsed_json, allowed_types)


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1 + ["auto"])
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_json_unsupported_schema(
    monkeypatch: pytest.MonkeyPatch,
    unsupported_json_schema: dict[str, Any],
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=1.0,
        max_tokens=1000,
        guided_decoding=GuidedDecodingParams(json=unsupported_json_schema))
    if guided_decoding_backend == "xgrammar":
        with pytest.raises(ValueError,
                           match="The provided JSON schema contains features "
                           "not supported by xgrammar."):
            llm.generate(prompts=[
                f"Give an example JSON for an employee profile "
                f"that fits this schema: {unsupported_json_schema}"
            ] * 2,
                         sampling_params=sampling_params,
                         use_tqdm=True)
    else:
        # This should work for both "guidance" and "auto".

        outputs = llm.generate(
            prompts=("Give an example JSON object for a grade "
                     "that fits this schema: "
                     f"{unsupported_json_schema}"),
            sampling_params=sampling_params,
            use_tqdm=True)
        assert outputs is not None
        for output in outputs:
            assert output is not None
            assert isinstance(output, RequestOutput)
            generated_text = output.outputs[0].text
            assert generated_text is not None
            print(generated_text)

            # Parse to verify it is valid JSON
            parsed_json = json.loads(generated_text)
            assert isinstance(parsed_json, dict)


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_grammar_ebnf(
    monkeypatch: pytest.MonkeyPatch,
    sample_sql_ebnf: str,
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=0.8,
        top_p=0.95,
        max_tokens=1000,
        guided_decoding=GuidedDecodingParams(grammar=sample_sql_ebnf))
    outputs = llm.generate(
        prompts=("Generate a sql statement that selects col_1 from "
                 "table_1 where it is equal to 1"),
        sampling_params=sampling_params,
        use_tqdm=True,
    )

    assert outputs is not None
    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)
        prompt = output.prompt

        generated_text = output.outputs[0].text
        assert generated_text is not None

        # remove spaces for comparison b/c we removed them in the grammar
        ground_truth = "SELECT col_1 from table_1 where col_1 = 1".replace(
            " ", "")

        assert generated_text.strip() == ground_truth

        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_grammar_lark(
    monkeypatch: pytest.MonkeyPatch,
    sample_sql_lark: str,
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=0.8,
        top_p=0.95,
        max_tokens=1000,
        guided_decoding=GuidedDecodingParams(grammar=sample_sql_lark))
    outputs = llm.generate(
        prompts=("Generate a sql statement that selects col_1 from "
                 "table_1 where it is equal to 1"),
        sampling_params=sampling_params,
        use_tqdm=True,
    )

    assert outputs is not None
    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)
        prompt = output.prompt

        generated_text = output.outputs[0].text
        assert generated_text is not None

        # use Lark to parse the output, and make sure it's a valid parse tree
        from lark import Lark
        parser = Lark(sample_sql_lark)
        parser.parse(generated_text)

        # remove spaces for comparison b/c we removed them in the grammar
        ground_truth = "SELECT col_1 from table_1 where col_1 = 1".replace(
            " ", "")

        assert generated_text.strip() == ground_truth

        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_grammar_ebnf_invalid(
    monkeypatch: pytest.MonkeyPatch,
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=0.8,
        top_p=0.95,
        max_tokens=1000,
        guided_decoding=GuidedDecodingParams(grammar="not a grammar"))
    with pytest.raises(ValueError, match="Failed to convert the grammar "):
        llm.generate(
            prompts=("Generate a sql statement that selects col_1 from "
                     "table_1 where it is equal to 1"),
            sampling_params=sampling_params,
            use_tqdm=True,
        )


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_regex(
    monkeypatch: pytest.MonkeyPatch,
    sample_regex: str,
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=0.8,
        top_p=0.95,
        guided_decoding=GuidedDecodingParams(regex=sample_regex))
    outputs = llm.generate(
        prompts=[
            f"Give an example IPv4 address with this regex: {sample_regex}"
        ] * 2,
        sampling_params=sampling_params,
        use_tqdm=True,
    )

    assert outputs is not None
    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)
        prompt = output.prompt
        generated_text = output.outputs[0].text
        print(generated_text)
        assert generated_text is not None
        assert re.fullmatch(sample_regex, generated_text) is not None
        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")


@pytest.mark.skip_global_cleanup
@pytest.mark.parametrize("guided_decoding_backend",
                         GUIDED_DECODING_BACKENDS_V1)
@pytest.mark.parametrize("model_name", MODELS_TO_TEST)
def test_guided_choice_completion(
    monkeypatch: pytest.MonkeyPatch,
    sample_guided_choice: str,
    guided_decoding_backend: str,
    model_name: str,
):
    monkeypatch.setenv("VLLM_USE_V1", "1")
    llm = LLM(model=model_name,
              max_model_len=1024,
              guided_decoding_backend=guided_decoding_backend)
    sampling_params = SamplingParams(
        temperature=0.8,
        top_p=0.95,
        guided_decoding=GuidedDecodingParams(choice=sample_guided_choice))
    outputs = llm.generate(
        prompts="The best language for type-safe systems programming is ",
        sampling_params=sampling_params,
        use_tqdm=True)
    assert outputs is not None
    for output in outputs:
        assert output is not None
        assert isinstance(output, RequestOutput)
        prompt = output.prompt
        generated_text = output.outputs[0].text
        print(generated_text)
        assert generated_text is not None
        assert generated_text in sample_guided_choice
        print(f"Prompt: {prompt!r}, Generated text: {generated_text!r}")
