// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Text.Json;
using Aspire.Cli.Backchannel;
using Aspire.Shared.ConsoleLogs;
using Microsoft.Extensions.Logging;
using ModelContextProtocol;
using ModelContextProtocol.Protocol;
 
namespace Aspire.Cli.Mcp.Tools;
 
/// <summary>
/// MCP tool for listing console logs for a resource.
/// Gets log data directly from the AppHost backchannel instead of forwarding to the dashboard.
/// </summary>
internal sealed class ListConsoleLogsTool(IAuxiliaryBackchannelMonitor auxiliaryBackchannelMonitor, ILogger<ListConsoleLogsTool> logger) : CliMcpTool
{
    public override string Name => KnownMcpTools.ListConsoleLogs;
 
    public override string Description => "List console logs for a resource. The console logs includes standard output from resources and resource commands. Known resource commands are 'resource-start', 'resource-stop' and 'resource-restart' which are used to start and stop resources. Don't print the full console logs in the response to the user. Console logs should be examined when determining why a resource isn't running.";
 
    public override JsonElement GetInputSchema()
    {
        return JsonDocument.Parse("""
            {
              "type": "object",
              "properties": {
                "resourceName": {
                  "type": "string",
                  "description": "The resource name."
                }
              },
              "required": ["resourceName"]
            }
            """).RootElement;
    }
 
    public override async ValueTask<CallToolResult> CallToolAsync(CallToolContext context, CancellationToken cancellationToken)
    {
        var arguments = context.Arguments;
 
        // Get the resource name from arguments
        string? resourceName = null;
        if (arguments is not null && arguments.TryGetValue("resourceName", out var resourceNameElement))
        {
            resourceName = resourceNameElement.GetString();
        }
 
        if (string.IsNullOrEmpty(resourceName))
        {
            throw new McpProtocolException("The resourceName parameter is required.", McpErrorCode.InvalidParams);
        }
 
        var connection = await AppHostConnectionHelper.GetSelectedConnectionAsync(auxiliaryBackchannelMonitor, logger, cancellationToken).ConfigureAwait(false);
        if (connection is null)
        {
            logger.LogWarning("No Aspire AppHost is currently running");
            throw new McpProtocolException(McpErrorMessages.NoAppHostRunning, McpErrorCode.InternalError);
        }
 
        try
        {
            var logParser = new LogParser(ConsoleColor.Black);
            var logEntries = new LogEntries(maximumEntryCount: SharedAIHelpers.ConsoleLogsLimit) { BaseLineNumber = 1 };
 
            // Collect logs from the backchannel
            await foreach (var logLine in connection.GetResourceLogsAsync(resourceName, follow: false, cancellationToken).ConfigureAwait(false))
            {
                logEntries.InsertSorted(logParser.CreateLogEntry(logLine.Content, logLine.IsError, resourceName));
            }
 
            var entries = logEntries.GetEntries().ToList();
            var totalLogsCount = entries.Count == 0 ? 0 : entries.Last().LineNumber;
            var (trimmedItems, limitMessage) = SharedAIHelpers.GetLimitFromEndWithSummary(
                entries,
                totalLogsCount,
                SharedAIHelpers.ConsoleLogsLimit,
                "console log",
                "console logs",
                SharedAIHelpers.SerializeLogEntry,
                SharedAIHelpers.EstimateTokenCount);
            var consoleLogsText = SharedAIHelpers.SerializeConsoleLogs(trimmedItems);
 
            var consoleLogsData = $"""
                {limitMessage}
 
                # CONSOLE LOGS
 
                ```plaintext
                {consoleLogsText.Trim()}
                ```
                """;
 
            return new CallToolResult
            {
                Content = [new TextContentBlock { Text = consoleLogsData }]
            };
        }
        catch (Exception ex) when (ex is not McpProtocolException)
        {
            logger.LogError(ex, "Error retrieving console logs for resource '{ResourceName}'", resourceName);
            return new CallToolResult
            {
                Content = [new TextContentBlock { Text = $"Error retrieving console logs for resource '{resourceName}': {ex.Message}" }]
            };
        }
    }
}