using System.ComponentModel;
using System.Text.Json;
using ModelContextProtocol.Protocol;
using ModelContextProtocol.Server;
using Sbroenne.ExcelMcp.Core.Commands.Screenshot;
namespace Sbroenne.ExcelMcp.McpServer.Tools;
/// <summary>
/// Manual MCP tool for screenshot operations.
/// Returns ImageContentBlock for proper MCP image handling.
/// </summary>
[McpServerToolType]
public static class ExcelScreenshotTool
{
/// <summary>
/// Capture Excel worksheet content as images for visual verification.
/// Uses Excel's built-in rendering to capture all visual elements (formatting, charts, conditional formatting).
/// capture: specific range (requires rangeAddress).
/// capture-sheet: entire used area of worksheet.
/// Returns the image directly as MCP ImageContent.
/// Use after operations to visually verify results.
/// quality: Medium (default, JPEG 75% scale, ~4-8x smaller), High (PNG full scale), Low (JPEG 50% scale).
/// </summary>
[McpServerTool(Name = "screenshot", Title = "Screenshot", Destructive = false)]
[McpMeta("category", "visualization")]
[McpMeta("requiresSession", true)]
[Description("Capture Excel worksheet content as images for visual verification. " +
"Uses Excel's built-in rendering to capture all visual elements (formatting, charts, conditional formatting). " +
"capture: specific range (requires rangeAddress). " +
"capture-sheet: entire used area of worksheet. " +
"Returns the image directly as MCP ImageContent. " +
"Use after operations to visually verify results. " +
"quality: Medium (default, JPEG 75% scale, ~4-8x smaller than High), High (PNG full scale), Low (JPEG 50% scale).")]
public static CallToolResult ExcelScreenshot(
[Description("The action to perform")] ScreenshotAction action,
[Description("Session ID from file 'open' action")] string session_id,
[DefaultValue(null)] string? sheet_name,
[DefaultValue("A1:Z30")] string range_address,
[DefaultValue(ScreenshotQuality.Medium)] ScreenshotQuality quality)
{
// Forward to service and get JSON response
var jsonResponse = ExcelToolsBase.ExecuteToolAction(
"screenshot",
ServiceRegistry.Screenshot.ToActionString(action),
() => ServiceRegistry.Screenshot.RouteAction(
action,
session_id,
ExcelToolsBase.ForwardToServiceFunc,
sheetName: sheet_name,
rangeAddress: range_address,
quality: quality
));
// Parse the JSON response to extract image data
try
{
var result = JsonSerializer.Deserialize<ScreenshotResult>(jsonResponse, ExcelToolsBase.JsonOptions);
if (result is null || !result.Success || string.IsNullOrEmpty(result.ImageBase64))
{
// Return error as text content
return new CallToolResult
{
IsError = true,
Content = [new TextContentBlock { Text = jsonResponse }]
};
}
// Return image as ImageContentBlock + metadata as TextContentBlock
var metadata = $"Screenshot: {result.RangeAddress} on '{result.SheetName}' ({result.Width}x{result.Height}px)";
return new CallToolResult
{
Content =
[
new ImageContentBlock
{
Data = result.ImageBase64,
MimeType = result.MimeType
},
new TextContentBlock
{
Text = metadata
}
]
};
}
catch (JsonException)
{
// If JSON parsing fails, return the raw response as error
return new CallToolResult
{
IsError = true,
Content = [new TextContentBlock { Text = jsonResponse }]
};
}
}
}
