Libation/Source/FileManager/FileNamingTemplate.cs
2022-06-23 13:01:24 -06:00

102 lines
3.1 KiB
C#

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
namespace FileManager
{
/// <summary>Get valid filename. Advanced features incl. parameterized template</summary>
public class FileNamingTemplate : NamingTemplate
{
/// <param name="template">Proposed file name with optional html-styled template tags.</param>
public FileNamingTemplate(string template) : base(template) { }
/// <summary>Generate a valid path for this file or directory</summary>
public LongPath GetFilePath(ReplacementCharacters replacements, bool returnFirstExisting = false)
{
string fileName = Template.EndsWith(Path.DirectorySeparatorChar) ? Template[..^1] : Template;
List<string> pathParts = new();
var paramReplacements = ParameterReplacements.ToDictionary(r => $"<{formatKey(r.Key)}>", r => formatValue(r.Value, replacements));
while (!string.IsNullOrEmpty(fileName))
{
var file = Path.GetFileName(fileName);
if (Path.IsPathRooted(Template) && file == string.Empty)
{
pathParts.Add(fileName);
break;
}
else
{
file = replaceFileName(file, paramReplacements);
fileName = Path.GetDirectoryName(fileName);
pathParts.Add(file);
}
}
pathParts.Reverse();
return FileUtility.GetValidFilename(Path.Join(pathParts.ToArray()), replacements, returnFirstExisting);
}
private string replaceFileName(string filename, Dictionary<string,string> paramReplacements)
{
List<StringBuilder> filenameParts = new();
//Build the filename in parts, replacing replacement parameters with
//their values, and storing the parts in a list.
while (!string.IsNullOrEmpty(filename))
{
int openIndex = filename.IndexOf('<');
int closeIndex = filename.IndexOf('>');
if (openIndex == 0 && closeIndex > 0)
{
var key = filename[..(closeIndex + 1)];
if (paramReplacements.ContainsKey(key))
filenameParts.Add(new StringBuilder(paramReplacements[key]));
else
filenameParts.Add(new StringBuilder(key));
filename = filename[(closeIndex + 1)..];
}
else if (openIndex > 0 && closeIndex > openIndex)
{
var other = filename[..openIndex];
filenameParts.Add(new StringBuilder(other));
filename = filename[openIndex..];
}
else
{
filenameParts.Add(new StringBuilder(filename));
filename = string.Empty;
}
}
//Remove 1 character from the end of the longest filename part until
//the total filename is less than max filename length
while (filenameParts.Sum(p => p.Length) > LongPath.MaxFilenameLength)
{
int maxLength = filenameParts.Max(p => p.Length);
var maxEntry = filenameParts.First(p => p.Length == maxLength);
maxEntry.Remove(maxLength - 1, 1);
}
return string.Join("", filenameParts);
}
private string formatValue(object value, ReplacementCharacters replacements)
{
if (value is null)
return "";
// Other illegal characters will be taken care of later. Must take care of slashes now so params can't introduce new folders.
// Esp important for file templates.
return replacements.ReplaceInvalidFilenameChars(value.ToString());
}
}
}