using AxCopilot.Services.Agent;
using FluentAssertions;
using Xunit;

namespace AxCopilot.Tests.Services;

public class AgentLoopDiagnosticsFormatterTests
{
    [Fact]
    public void BuildCompactionCompleteMessage_ShouldIncludeStageSummaryAndSavedTokens()
    {
        var result = new ContextCompactionResult
        {
            BeforeTokens = 18_400,
            AfterTokens = 7_900,
        };
        result.AppliedStages.Add("tool-result");
        result.AppliedStages.Add("session-memory");

        var message = AgentLoopDiagnosticsFormatter.BuildCompactionCompleteMessage(result);

        message.Should().Be("Context compaction complete: tool-result -> session-memory, saved 10.3K tokens");
    }

    [Fact]
    public void BuildQueryViewSummary_ShouldIncludeWindowAndPreviewReuseMetrics()
    {
        var result = new AgentQueryContextWindowResult
        {
            Messages = new(),
            SourceMessageCount = 34,
            ViewMessageCount = 12,
            WindowStartIndex = 21,
            BoundaryApplied = true,
            ToolPairExpanded = true,
            PreservedToolPairCount = 2,
            TruncatedToolResultCount = 3,
            ReusedToolResultPreviewCount = 4,
            TokensBeforeBudget = 8_600,
            TokensAfterBudget = 6_100,
        };

        var summary = AgentLoopDiagnosticsFormatter.BuildQueryViewSummary(result);

        summary.Should().Be("query-view 34->12, start=21, pairs=2, tool_result_budget=3, tool_result_preview_reuse=4, tokens 8600->6100");
    }
}