using Sbroenne.ExcelMcp.ComInterop;
namespace Sbroenne.ExcelMcp.Core.Commands.Chart;
/// <summary>
/// Helpers for chart positioning: collision detection against data ranges and other charts.
/// </summary>
internal static class ChartPositionHelpers
{
/// <summary>
/// Detects collisions between a chart's proposed position and existing content on the worksheet.
/// Checks against the used range (data) and all other chart shapes.
/// </summary>
/// <param name="worksheet">Target worksheet COM object</param>
/// <param name="left">Proposed chart left position in points</param>
/// <param name="top">Proposed chart top position in points</param>
/// <param name="width">Proposed chart width in points</param>
/// <param name="height">Proposed chart height in points</param>
/// <param name="excludeChartName">Chart name to exclude from collision checks (for move/resize operations on an existing chart)</param>
/// <returns>List of collision warning messages, empty if no collisions</returns>
internal static List<string> DetectCollisions(
dynamic worksheet,
double left,
double top,
double width,
double height,
string? excludeChartName = null)
{
var warnings = new List<string>();
// Check collision with used range (data area)
CheckUsedRangeCollision(worksheet, left, top, width, height, warnings);
// Check collision with other charts
CheckChartCollisions(worksheet, left, top, width, height, excludeChartName, warnings);
return warnings;
}
/// <summary>
/// Finds the first available position below or to the right of all existing content (used range + charts)
/// on the worksheet for a chart with the given dimensions.
/// </summary>
/// <param name="worksheet">Target worksheet COM object</param>
/// <param name="width">Desired chart width in points</param>
/// <param name="height">Desired chart height in points</param>
/// <param name="padding">Padding in points between content and chart (default: 10pt)</param>
/// <returns>Tuple of (left, top) position in points for the chart</returns>
internal static (double Left, double Top) FindAvailablePosition(
dynamic worksheet,
double width = 400,
double height = 300,
double padding = 10.0)
{
double maxBottom = 0;
double maxRight = 0;
// Get used range boundary
dynamic? usedRange = null;
try
{
usedRange = worksheet.UsedRange;
double urLeft = Convert.ToDouble(usedRange.Left);
double urTop = Convert.ToDouble(usedRange.Top);
double urWidth = Convert.ToDouble(usedRange.Width);
double urHeight = Convert.ToDouble(usedRange.Height);
maxBottom = Math.Max(maxBottom, urTop + urHeight);
maxRight = Math.Max(maxRight, urLeft + urWidth);
}
finally
{
ComUtilities.Release(ref usedRange!);
}
// Get chart boundaries
dynamic? shapes = null;
try
{
shapes = worksheet.Shapes;
int shapeCount = Convert.ToInt32(shapes.Count);
for (int j = 1; j <= shapeCount; j++)
{
dynamic? shape = null;
try
{
shape = shapes.Item(j);
// Only consider chart shapes (msoChart = 3)
if (Convert.ToInt32(shape.Type) != 3)
{
continue;
}
double sLeft = Convert.ToDouble(shape.Left);
double sTop = Convert.ToDouble(shape.Top);
double sWidth = Convert.ToDouble(shape.Width);
double sHeight = Convert.ToDouble(shape.Height);
maxBottom = Math.Max(maxBottom, sTop + sHeight);
maxRight = Math.Max(maxRight, sLeft + sWidth);
}
finally
{
ComUtilities.Release(ref shape!);
}
}
}
finally
{
ComUtilities.Release(ref shapes!);
}
// Strategy: place chart below all existing content, aligned to left edge of used range
// If the chart would fit to the right of the used range (within reasonable horizontal space),
// place it there instead for a side-by-side layout.
// For now, always place below to avoid horizontal overflow.
_ = width; // Reserved for future side-by-side layout consideration
_ = height; // Reserved for future vertical space check
return (padding, maxBottom + padding);
}
/// <summary>
/// Counts the number of chart shapes on a worksheet.
/// </summary>
internal static int CountCharts(dynamic worksheet)
{
int count = 0;
dynamic? shapes = null;
try
{
shapes = worksheet.Shapes;
int shapeCount = Convert.ToInt32(shapes.Count);
for (int j = 1; j <= shapeCount; j++)
{
dynamic? shape = null;
try
{
shape = shapes.Item(j);
if (Convert.ToInt32(shape.Type) == 3) // msoChart
{
count++;
}
}
finally
{
ComUtilities.Release(ref shape!);
}
}
}
finally
{
ComUtilities.Release(ref shapes!);
}
return count;
}
/// <summary>
/// Formats chart positioning feedback for the result message.
/// Always includes a screenshot verification reminder.
/// When collisions are detected, includes overlap warnings with remediation guidance.
/// When multiple charts exist on the sheet, uses stronger language to ensure screenshot verification.
/// </summary>
/// <param name="warnings">Collision warnings (empty if no overlaps detected)</param>
/// <param name="chartCount">Number of charts on the worksheet (including the one just created/moved)</param>
internal static string FormatCollisionWarnings(List<string> warnings, int chartCount = 1)
{
if (warnings.Count > 0)
{
return $"OVERLAP WARNING: {string.Join("; ", warnings)}. Use chart move or fit-to-range to reposition, then screenshot(capture-sheet) to verify layout.";
}
if (chartCount >= 2)
{
return $"IMPORTANT: {chartCount} charts now on this sheet. You MUST take a screenshot(capture-sheet) to verify no charts overlap each other or the data.";
}
return "IMPORTANT: You MUST take a screenshot(capture-sheet) to verify the chart does not overlap the data.";
}
private static void CheckUsedRangeCollision(
dynamic worksheet,
double left,
double top,
double width,
double height,
List<string> warnings)
{
dynamic? usedRange = null;
try
{
usedRange = worksheet.UsedRange;
double urLeft = Convert.ToDouble(usedRange.Left);
double urTop = Convert.ToDouble(usedRange.Top);
double urWidth = Convert.ToDouble(usedRange.Width);
double urHeight = Convert.ToDouble(usedRange.Height);
string? urAddress = null;
try
{
urAddress = usedRange.Address?.ToString();
}
catch
{
urAddress = "(unknown)";
}
if (RectsOverlap(left, top, width, height, urLeft, urTop, urWidth, urHeight))
{
warnings.Add($"Chart overlaps data area {urAddress}");
}
}
finally
{
ComUtilities.Release(ref usedRange!);
}
}
private static void CheckChartCollisions(
dynamic worksheet,
double left,
double top,
double width,
double height,
string? excludeChartName,
List<string> warnings)
{
dynamic? shapes = null;
try
{
shapes = worksheet.Shapes;
int shapeCount = Convert.ToInt32(shapes.Count);
for (int j = 1; j <= shapeCount; j++)
{
dynamic? shape = null;
try
{
shape = shapes.Item(j);
// Only check chart shapes (msoChart = 3)
if (Convert.ToInt32(shape.Type) != 3)
{
continue;
}
string shapeName = shape.Name?.ToString() ?? string.Empty;
// Skip the chart being created/moved
if (excludeChartName != null &&
shapeName.Equals(excludeChartName, StringComparison.OrdinalIgnoreCase))
{
continue;
}
double sLeft = Convert.ToDouble(shape.Left);
double sTop = Convert.ToDouble(shape.Top);
double sWidth = Convert.ToDouble(shape.Width);
double sHeight = Convert.ToDouble(shape.Height);
if (RectsOverlap(left, top, width, height, sLeft, sTop, sWidth, sHeight))
{
warnings.Add($"Chart overlaps existing chart '{shapeName}'");
}
}
finally
{
ComUtilities.Release(ref shape!);
}
}
}
finally
{
ComUtilities.Release(ref shapes!);
}
}
/// <summary>
/// Checks if two rectangles overlap (in point coordinates).
/// Returns false if they merely touch edges (share a boundary).
/// </summary>
private static bool RectsOverlap(
double x1, double y1, double w1, double h1,
double x2, double y2, double w2, double h2)
{
// No overlap if one is completely to the left, right, above, or below the other
// Use strict < (not <=) so touching edges are NOT considered overlaps
return x1 < x2 + w2 &&
x1 + w1 > x2 &&
y1 < y2 + h2 &&
y1 + h1 > y2;
}
}
