using System;
using System.Collections.Generic;

using JetBrains.Metadata.Reader.API;
using JetBrains.ProjectModel;
using JetBrains.ReSharper.Psi;
using JetBrains.ReSharper.UnitTestExplorer;

using MbUnit.ReSharperRunner.Elements;

namespace MbUnit.ReSharperRunner.Explorer
{
    internal class MbUnitAssemblyExplorer
    {
        private CLRTypeName ignoreAttribute = new CLRTypeName(AttributesNames.IgnoreAttributeName);
        private CLRTypeName categoryAttribute = new CLRTypeName(AttributesNames.TestCategoryAttributeName);
        private readonly AssemblyHelper helper = new AssemblyHelper();

        public void ExploreAssembly(IUnitTestProvider provider, IMetadataAssembly assembly, IProject project,
                                    UnitTestElementConsumer consumer)
        {
            if (provider == null)
            {
                throw new ArgumentNullException("provider");
            }
            if (assembly == null)
            {
                throw new ArgumentNullException("assembly");
            }
            if (project == null)
            {
                throw new ArgumentNullException("project");
            }
            if (consumer == null)
            {
                throw new ArgumentNullException("consumer");
            }
            foreach (IMetadataTypeInfo type in assembly.GetTypes())
            {
                if (helper.IsTestFixture(type))
                {
                    List<string> fixtureCategories = new List<string>();
                    helper.CollectTestFixtureCategories(type, ref fixtureCategories);
                    MbUnitTestFixtureElement fixture =
                        new MbUnitTestFixtureElement(provider, project,
                                                     type.FullyQualifiedName,
                                                     assembly.Location,
                                                     helper.GetTestFixtureName(type));

                    fixture.AssignCategories(fixtureCategories);
                    fixture.SetExplicit(GetExplicitString(type));
                    consumer(fixture);
                    foreach (IMetadataMethod method in helper.GetAllTestMethods(type))
                    {
                        if (helper.IsTestMethod(method))
                        {
                            List<string> methodCategories = new List<string>(fixtureCategories);
                            helper.CollectTestMethodCategories(method, ref methodCategories);
                            MbUnitTestElement testElement = new MbUnitTestElement(
                                provider, fixture, project, method.DeclaringType.FullyQualifiedName,
                                helper.GetMethodName(method),
                                helper.GetTestName(method));
                            if (helper.HasChildTest(method))
                            {
                                foreach (string childName in helper.GetChildNames(method))
                                {
                                    MbUnitChildTestElement childTest =
                                        new MbUnitChildTestElement(testElement, provider, project,
                                                                   method.DeclaringType.FullyQualifiedName, childName,
                                                                   helper.GetTestName(method));
                                    childTest.AssignCategories(methodCategories);
                                    consumer(childTest);
                                }
                            }
                            //                    testElement.SetExplicit(GetExplicitString(method));
                            testElement.AssignCategories(methodCategories);
                            consumer(testElement);
                        }
                    }
                }
            }
        }

        private string GetExplicitString(IMetadataEntity method)
        {
            IMetadataCustomAttribute[] attributes = method.GetCustomAttributes(ignoreAttribute.ClrName);
            string reason = null;
            for (int i = 0; i < attributes.Length; i++)
            {
                object[] arguments = attributes[i].ConstructorArguments;
                if (arguments.Length == 1)
                {
                    string r = arguments[0] as string;
                    if (r == null)
                    {
                        if (reason == null)
                        {
                            reason = "";
                        }
                    }
                    else
                    {
                        reason = r;
                    }
                }
                else if (reason == null)
                {
                    reason = "";
                }
            }
            return reason;
        }
    }
}