/// <summary>
/// Creates a usage description for the command associated with the provided
/// 'parameterObject'.
/// <para>
/// The usage description is either the one provided with
/// the 'UsageAttribute' or a generic description created from the known
/// parameter attributes.
/// </para>
/// <para>
/// The result string is supposed to be rendered on the command line.
/// </para>
/// </summary>
/// <param name="parameterObject"></param>
/// <param name="screenWidth"></param>
/// <returns>The resulting string</returns>
public virtual string CreateUsage(ParameterBase parameterObject, int screenWidth = 80)
{
string result;
string usage;
result = String.Empty;
result += CreateUsageHeader(screenWidth);
result += "Usage:\r\n\r\n";
UsageAttribute? usageAttribute = (UsageAttribute?)parameterObject.GetType().GetCustomAttribute(typeof(UsageAttribute));
//
// If a usage description is provided in the command attributes return that description.
//
if ((usageAttribute != null) && !String.IsNullOrWhiteSpace(usageAttribute.Usage))
{
usage = usageAttribute.Usage;
}
//
// Create a usage description from the known parameter attributes.
//
else
{
usage = parameterObject.CommandName + " ";
usage += "[" + parameterObject.HelpIndicatorList.First() + "] ";
usage += "[" + parameterObject.VersionIndicatorList.First() + "] ";
foreach (var metaInfo in parameterObject.PropertyMetaInfoList)
{
if (metaInfo.IsMandatory)
{
usage += metaInfo.Name + "=" + "<" + metaInfo.Type + "> ";
}
else
{
usage += "[" + metaInfo.Name + "=" + "<" + metaInfo.Type + ">" + "] ";
}
}
}
List<string> lines = CreateWrappedLines(usage, screenWidth, 0);
return result + String.Join("\r\n", lines);
}
const char Asterisk = '*'; // *
// ************************************************************************
// IDisplayHelper implementation START
// ************************************************************************
/// <summary>
/// Creates the help screen for the parameter object provided in argument
/// 'parameterObject'.
/// <para>
/// The line length of the resulting help text will match with value provide in argument 'screenWidth'
/// as long a the value is greater than the minimum screen line length. Otherwise the minimum screen
/// line length will be used.
/// </para>
/// <para>
/// The result string is supposed to be rendered on the command line.
/// </para>
/// </summary>
/// <param name="parameterObject"></param>
/// <param name="screenWidth"></param>
/// <returns>The resulting string</returns>
public virtual string CreateHelp(ParameterBase parameterObject, int screenWidth = 80)
{
string result;
int longestArgumentLength;
int longestTypeLength;
int longestDefaultLength;
string help;
List<string> helpLines;
result = string.Empty;
longestArgumentLength = 0;
if (parameterObject == null)
{
return result;
}
HelpAttribute? helpAttribute = (HelpAttribute?)parameterObject.GetType().GetCustomAttribute(typeof(HelpAttribute));
//
// If a help text is provided in the command attributes show that text first.
//
if ((helpAttribute != null) && !String.IsNullOrWhiteSpace(helpAttribute.Help))
{
help = helpAttribute.Help;
}
else
{
help = string.Empty;
}
if (parameterObject.PropertyMetaInfoList.Count == 0)
{
result = "The current parameter object has no parameter property!";
}
else
{
longestArgumentLength = parameterObject.PropertyMetaInfoList.Max(item => item.Name.Length);
longestTypeLength = parameterObject.PropertyMetaInfoList.Max(item => item.Type.Length);
longestDefaultLength = parameterObject.PropertyMetaInfoList.Max(item => (item.DefaultValue?.ToString()?.Length ?? 0));
longestArgumentLength = Math.Max(longestArgumentLength, "[Parameter]".Length); // [Parameter] = 11 characters min
longestTypeLength = Math.Max(longestTypeLength, "[Type]".Length); // [Type] = 6 characters min
longestDefaultLength = Math.Max(longestDefaultLength, "[Default]".Length); // [Default] = 9 characters min
//
// Expand the screen width if there isn't at least 20 characters left for the description.
// Minimum length for the help screen is 11 + 6 + 9 + 20 for parameter, type default and description
// plus additional 15 characters for spaces and borders. That is 61 characters minimum.
//
if((longestArgumentLength + longestTypeLength + longestDefaultLength + 20) > screenWidth)
{
screenWidth = (longestArgumentLength + longestTypeLength + longestDefaultLength + 20);
}
if(!String.IsNullOrWhiteSpace(help))
{
//
// Format the help text from the help attribute.
//
helpLines = CreateWrappedLines(help, screenWidth, leadingSpaces:0, keepEmptyLines:true);
result += "\r\n" + String.Join("\r\n", helpLines) + "\r\n\r\n";
}
result += CreateHelpHeader(screenWidth);
result += CreateHelpTop(screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
result += CreateHelpAndVersionArgumentHelpLines(parameterObject.HelpIndicatorList.First(), "Shows the help screen. (This screen).", screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
result += CreateHelpSeparatorLine(screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
result += CreateHelpAndVersionArgumentHelpLines(parameterObject.VersionIndicatorList.First(), "Shows the command version number if available or an empty string. (Nothing)", screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
result += CreateHelpSeparatorLine(screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
for (int index = 0; index < parameterObject.PropertyMetaInfoList.Count; index++)
{
result += CreateHelpLines(parameterObject.PropertyMetaInfoList[index], screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
if (index < parameterObject.PropertyMetaInfoList.Count - 1)
{
result += CreateHelpSeparatorLine(screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
}
}
result += CreateHelpBottom(screenWidth, longestArgumentLength, longestTypeLength, longestDefaultLength);
}
result += "\r\n\r\n";
result += CreateUsage(parameterObject);
return result;
}
