import json

import pytest

from vllm.entrypoints.openai.cli_args import (make_arg_parser,
                                              validate_parsed_serve_args)
from vllm.entrypoints.openai.serving_models import LoRAModulePath
from vllm.utils import FlexibleArgumentParser

from ...utils import VLLM_PATH

LORA_MODULE = {
    "name": "module2",
    "path": "/path/to/module2",
    "base_model_name": "llama"
}
CHATML_JINJA_PATH = VLLM_PATH / "examples/template_chatml.jinja"
assert CHATML_JINJA_PATH.exists()


@pytest.fixture
def serve_parser():
    parser = FlexibleArgumentParser(description="vLLM's remote OpenAI server.")
    return make_arg_parser(parser)


### Tests for Lora module parsing
def test_valid_key_value_format(serve_parser):
    # Test old format: name=path
    args = serve_parser.parse_args([
        '--lora-modules',
        'module1=/path/to/module1',
    ])
    expected = [LoRAModulePath(name='module1', path='/path/to/module1')]
    assert args.lora_modules == expected


def test_valid_json_format(serve_parser):
    # Test valid JSON format input
    args = serve_parser.parse_args([
        '--lora-modules',
        json.dumps(LORA_MODULE),
    ])
    expected = [
        LoRAModulePath(name='module2',
                       path='/path/to/module2',
                       base_model_name='llama')
    ]
    assert args.lora_modules == expected


def test_invalid_json_format(serve_parser):
    # Test invalid JSON format input, missing closing brace
    with pytest.raises(SystemExit):
        serve_parser.parse_args([
            '--lora-modules', '{"name": "module3", "path": "/path/to/module3"'
        ])


def test_invalid_type_error(serve_parser):
    # Test type error when values are not JSON or key=value
    with pytest.raises(SystemExit):
        serve_parser.parse_args([
            '--lora-modules',
            'invalid_format'  # This is not JSON or key=value format
        ])


def test_invalid_json_field(serve_parser):
    # Test valid JSON format but missing required fields
    with pytest.raises(SystemExit):
        serve_parser.parse_args([
            '--lora-modules',
            '{"name": "module4"}'  # Missing required 'path' field
        ])


def test_empty_values(serve_parser):
    # Test when no LoRA modules are provided
    args = serve_parser.parse_args(['--lora-modules', ''])
    assert args.lora_modules == []


def test_multiple_valid_inputs(serve_parser):
    # Test multiple valid inputs (both old and JSON format)
    args = serve_parser.parse_args([
        '--lora-modules',
        'module1=/path/to/module1',
        json.dumps(LORA_MODULE),
    ])
    expected = [
        LoRAModulePath(name='module1', path='/path/to/module1'),
        LoRAModulePath(name='module2',
                       path='/path/to/module2',
                       base_model_name='llama')
    ]
    assert args.lora_modules == expected


### Tests for serve argument validation that run prior to loading
def test_enable_auto_choice_passes_without_tool_call_parser(serve_parser):
    """Ensure validation fails if tool choice is enabled with no call parser"""
    # If we enable-auto-tool-choice, explode with no tool-call-parser
    args = serve_parser.parse_args(args=["--enable-auto-tool-choice"])
    with pytest.raises(TypeError):
        validate_parsed_serve_args(args)


def test_enable_auto_choice_passes_with_tool_call_parser(serve_parser):
    """Ensure validation passes with tool choice enabled with a call parser"""
    args = serve_parser.parse_args(args=[
        "--enable-auto-tool-choice",
        "--tool-call-parser",
        "mistral",
    ])
    validate_parsed_serve_args(args)


def test_enable_auto_choice_fails_with_enable_reasoning(serve_parser):
    """Ensure validation fails if reasoning is enabled with auto tool choice"""
    args = serve_parser.parse_args(args=[
        "--enable-auto-tool-choice",
        "--enable-reasoning",
    ])
    with pytest.raises(TypeError):
        validate_parsed_serve_args(args)


def test_enable_reasoning_passes_with_reasoning_parser(serve_parser):
    """Ensure validation passes if reasoning is enabled 
    with a reasoning parser"""
    args = serve_parser.parse_args(args=[
        "--enable-reasoning",
        "--reasoning-parser",
        "deepseek_r1",
    ])
    validate_parsed_serve_args(args)


def test_enable_reasoning_fails_without_reasoning_parser(serve_parser):
    """Ensure validation fails if reasoning is enabled 
    without a reasoning parser"""
    args = serve_parser.parse_args(args=["--enable-reasoning"])
    with pytest.raises(TypeError):
        validate_parsed_serve_args(args)


def test_chat_template_validation_for_happy_paths(serve_parser):
    """Ensure validation passes if the chat template exists"""
    args = serve_parser.parse_args(
        args=["--chat-template",
              CHATML_JINJA_PATH.absolute().as_posix()])
    validate_parsed_serve_args(args)


def test_chat_template_validation_for_sad_paths(serve_parser):
    """Ensure validation fails if the chat template doesn't exist"""
    args = serve_parser.parse_args(args=["--chat-template", "does/not/exist"])
    with pytest.raises(ValueError):
        validate_parsed_serve_args(args)