sourcegit/src/Models/CommitGraph.cs
2024-10-15 19:46:44 +08:00

341 lines
11 KiB
C#

using System;
using System.Collections.Generic;
using Avalonia;
using Avalonia.Media;
namespace SourceGit.Models
{
public class CommitGraph
{
public static List<Pen> Pens { get; } = [];
public static void SetDefaultPens(double thickness = 2)
{
SetPens(s_defaultPenColors, thickness);
}
public static void SetPens(List<Color> colors, double thickness)
{
Pens.Clear();
foreach (var c in colors)
Pens.Add(new Pen(c.ToUInt32(), thickness));
s_penCount = colors.Count;
}
public class Path(int color)
{
public List<Point> Points { get; } = [];
public int Color { get; } = color;
}
public class Link
{
public Point Start;
public Point Control;
public Point End;
public int Color;
}
public enum DotType
{
Default,
Head,
Merge,
}
public class Dot
{
public DotType Type;
public Point Center;
public int Color;
}
public List<Path> Paths { get; } = [];
public List<Link> Links { get; } = [];
public List<Dot> Dots { get; } = [];
public static CommitGraph Parse(List<Commit> commits, bool firstParentOnlyEnabled)
{
const double unitWidth = 12;
const double halfWidth = 6;
const double unitHeight = 28;
const double halfHeight = 14;
var temp = new CommitGraph();
var unsolved = new List<PathHelper>();
var ended = new List<PathHelper>();
var offsetY = -halfHeight;
var colorIdx = 0;
foreach (var commit in commits)
{
var major = null as PathHelper;
var isMerged = commit.IsMerged;
// Update current y offset
offsetY += unitHeight;
// Find first curves that links to this commit and marks others that links to this commit ended.
var offsetX = 4 - halfWidth;
var maxOffsetOld = unsolved.Count > 0 ? unsolved[^1].LastX : offsetX + unitWidth;
foreach (var l in unsolved)
{
if (l.Next.Equals(commit.SHA, StringComparison.Ordinal))
{
if (major == null)
{
offsetX += unitWidth;
major = l;
if (commit.Parents.Count > 0)
{
major.Next = commit.Parents[0];
major.Goto(offsetX, offsetY, halfHeight);
}
else
{
major.End(offsetX, offsetY, halfHeight);
ended.Add(l);
}
}
else
{
l.End(major.LastX, offsetY, halfHeight);
ended.Add(l);
}
isMerged = isMerged || l.IsMerged;
major.IsMerged = isMerged;
}
else
{
offsetX += unitWidth;
l.Pass(offsetX, offsetY, halfHeight);
}
}
// Remove ended curves from unsolved
foreach (var l in ended)
unsolved.Remove(l);
ended.Clear();
// Create new curve for branch head
if (major == null)
{
offsetX += unitWidth;
if (commit.Parents.Count > 0)
{
major = new PathHelper(commit.Parents[0], isMerged, colorIdx, new Point(offsetX, offsetY));
unsolved.Add(major);
temp.Paths.Add(major.Path);
}
colorIdx = (colorIdx + 1) % s_penCount;
}
// Calculate link position of this commit.
var position = new Point(major?.LastX ?? offsetX, offsetY);
var dotColor = major?.Path.Color ?? 0;
var anchor = new Dot() { Center = position, Color = dotColor };
if (commit.IsCurrentHead)
anchor.Type = DotType.Head;
else if (commit.Parents.Count > 1)
anchor.Type = DotType.Merge;
else
anchor.Type = DotType.Default;
temp.Dots.Add(anchor);
// Deal with other parents (the first parent has been processed)
if (!firstParentOnlyEnabled)
{
for (int j = 1; j < commit.Parents.Count; j++)
{
var parentHash = commit.Parents[j];
var parent = unsolved.Find(x => x.Next.Equals(parentHash, StringComparison.Ordinal));
if (parent != null)
{
// Try to change the merge state of linked graph
if (isMerged)
parent.IsMerged = true;
temp.Links.Add(new Link
{
Start = position,
End = new Point(parent.LastX, offsetY + halfHeight),
Control = new Point(parent.LastX, position.Y),
Color = parent.Path.Color
});
}
else
{
offsetX += unitWidth;
// Create new curve for parent commit that not includes before
var l = new PathHelper(parentHash, isMerged, colorIdx, position, new Point(offsetX, position.Y + halfHeight));
unsolved.Add(l);
temp.Paths.Add(l.Path);
colorIdx = (colorIdx + 1) % s_penCount;
}
}
}
// Margins & merge state (used by Views.Histories).
commit.IsMerged = isMerged;
commit.Margin = new Thickness(Math.Max(offsetX, maxOffsetOld) + halfWidth + 2, 0, 0, 0);
commit.Color = dotColor;
}
// Deal with curves haven't ended yet.
for (var i = 0; i < unsolved.Count; i++)
{
var path = unsolved[i];
var endY = (commits.Count - 0.5) * unitHeight;
if (path.Path.Points.Count == 1 && Math.Abs(path.Path.Points[0].Y - endY) < 0.0001)
continue;
path.End((i + 0.5) * unitWidth + 4, endY + halfHeight, halfHeight);
}
unsolved.Clear();
return temp;
}
private class PathHelper
{
public Path Path { get; }
public string Next { get; set; }
public bool IsMerged { get; set; }
public double LastX { get; private set; }
public PathHelper(string next, bool isMerged, int color, Point start)
{
Next = next;
IsMerged = isMerged;
LastX = start.X;
_lastY = start.Y;
Path = new Path(color);
Path.Points.Add(start);
}
public PathHelper(string next, bool isMerged, int color, Point start, Point to)
{
Next = next;
IsMerged = isMerged;
LastX = to.X;
_lastY = to.Y;
Path = new Path(color);
Path.Points.Add(start);
Path.Points.Add(to);
}
/// <summary>
/// A path that just passed this row.
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="halfHeight"></param>
public void Pass(double x, double y, double halfHeight)
{
if (x > LastX)
{
Add(LastX, _lastY);
Add(x, y - halfHeight);
}
else if (x < LastX)
{
Add(LastX, y - halfHeight);
y += halfHeight;
Add(x, y);
}
LastX = x;
_lastY = y;
}
/// <summary>
/// A path that has commit in this row but not ended
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="halfHeight"></param>
public void Goto(double x, double y, double halfHeight)
{
if (x > LastX)
{
Add(LastX, _lastY);
Add(x, y - halfHeight);
}
else if (x < LastX)
{
var minY = y - halfHeight;
if (minY > _lastY)
minY -= halfHeight;
Add(LastX, minY);
Add(x, y);
}
LastX = x;
_lastY = y;
}
/// <summary>
/// A path that has commit in this row and end.
/// </summary>
/// <param name="x"></param>
/// <param name="y"></param>
/// <param name="halfHeight"></param>
public void End(double x, double y, double halfHeight)
{
if (x > LastX)
{
Add(LastX, _lastY);
Add(x, y - halfHeight);
}
else if (x < LastX)
{
Add(LastX, y - halfHeight);
}
Add(x, y);
LastX = x;
_lastY = y;
}
private void Add(double x, double y)
{
if (_endY < y)
{
Path.Points.Add(new Point(x, y));
_endY = y;
}
}
private double _lastY = 0;
private double _endY = 0;
}
private static int s_penCount = 0;
private static readonly List<Color> s_defaultPenColors = [
Colors.Orange,
Colors.ForestGreen,
Colors.Gray,
Colors.Turquoise,
Colors.Olive,
Colors.Magenta,
Colors.Red,
Colors.Khaki,
Colors.Lime,
Colors.RoyalBlue,
Colors.Teal,
];
}
}