using SQLInsight.Collectors.Performance;

namespace SQLInsight.Collectors.Tests;

public class ShowplanAnalyzerTests
{
    private const string Plan = """
        <ShowPlanXML xmlns="http://schemas.microsoft.com/sqlserver/2004/07/showplan" Version="1.564" Build="16.0.4295.3">
          <BatchSequence><Batch><Statements><StmtSimple StatementText="SELECT ...">
            <QueryPlan>
              <Warnings>
                <PlanAffectingConvert ConvertIssue="Cardinality Estimate" Expression="CONVERT_IMPLICIT(nvarchar(20),[x].[Code],0)" />
                <PlanAffectingConvert ConvertIssue="Seek Plan" Expression="CONVERT_IMPLICIT(nvarchar(20),[x].[Code],0)=[@code]" />
              </Warnings>
              <RelOp PhysicalOp="Nested Loops">
                <Warnings NoJoinPredicate="true">
                  <ColumnsWithNoStatistics><ColumnReference Table="[Orders]" Column="Status" /></ColumnsWithNoStatistics>
                </Warnings>
                <ComputeScalar><DefinedValues><DefinedValue><ScalarOperator>
                  <UserDefinedFunction FunctionName="[Sales].[dbo].[fn_Price]" />
                </ScalarOperator></DefinedValue></DefinedValues></ComputeScalar>
              </RelOp>
            </QueryPlan>
          </StmtSimple></Statements></Batch></BatchSequence>
        </ShowPlanXML>
        """;

    [Fact]
    public void Finds_the_warnings_that_matter()
    {
        var warnings = ShowplanAnalyzer.Analyze(Plan);

        Assert.Equal(["CONVERT_IMPLICIT(nvarchar(20),[x].[Code],0)=[@code]"], warnings.SeekPreventingConversions);
        Assert.True(warnings.NoJoinPredicate);
        Assert.Equal(["[Sales].[dbo].[fn_Price]"], warnings.ScalarUdfs);
        Assert.Equal(["[Orders].Status"], warnings.ColumnsWithNoStatistics);
        Assert.False(warnings.NotAnalyzed);
    }

    [Theory]
    [InlineData(null)]
    [InlineData("")]
    [InlineData("<not-closed")]
    public void Missing_or_broken_plans_are_marked_not_analyzed(string? plan)
    {
        Assert.True(ShowplanAnalyzer.Analyze(plan).NotAnalyzed);
    }

    [Fact]
    public void Dtd_is_rejected()
    {
        Assert.True(ShowplanAnalyzer.Analyze("<!DOCTYPE x [<!ENTITY e SYSTEM \"file:///etc/passwd\">]><x>&e;</x>").NotAnalyzed);
    }
}