private IDirectiveParser CreateParser(string directive, DirectiveHolder current)
{
switch (directive.ToLower())
{
case "if": return(new IfParser(_metadataContainer));
case "list": return(new ListDirective(_metadataContainer));
case "elseif":
{
current.ApplyInDirective("else");
return(new IfParser(_metadataContainer));
}
}
throw new Exception($"Directive {directive} is not supported.");
}
private void SetTemplate(string template)
{
var matches =
Regex.Matches(template, @"\$\{([^\}]*)\}").OfType <Match>()
.Select(item => new { match = item, type = PlaceholderType.Field })
.Union(
Regex.Matches(template, @"(?:<|<)#([[a-zA-Z]*)[\s]([^>&]*)(:?>|>)")
.OfType <Match>()
.Select(item => new { match = item, type = PlaceholderType.Directive }))
.Union(
Regex.Matches(template, @"(?:<|<)#([[a-zA-Z]*)(:?>|>)")
.OfType <Match>()
.Select(item => new { match = item, type = PlaceholderType.InDirective }))
.Union(
Regex.Matches(template, @"(?:<|<)\/#([[a-zA-Z]*)(:?>|>)")
.OfType <Match>()
.Select(item => new { match = item, type = PlaceholderType.DirectiveEnd }));
_placeholders = new List <IPlaceholder>();
var templateIndex = 0;
var position = 0;
var directives = new Stack <DirectiveHolder>();
DirectiveHolder currentDirective = null;
var holders = _placeholders;
foreach (var match in matches.OrderBy(item => item.match.Index))
{
var text = template.Substring(templateIndex, match.match.Index - templateIndex);
holders.Add(new TextHolder(text, position++));
templateIndex = match.match.Index + match.match.Length;
switch (match.type)
{
case PlaceholderType.Field:
{
var value = match.match.Value.Trim('$', '{', '}');
holders.Add(value.StartsWith(".")
? (IPlaceholder) new FunctionHolder(_metadataContainer, value, position++)
: new Placeholder(_metadataContainer, value, position++));
break;
}
case PlaceholderType.Directive:
{
var directive = match.match.Groups[1].Value;
var parser = CreateParser(directive, currentDirective);
if (currentDirective != null)
{
directives.Push(currentDirective);
holders = currentDirective.CurrentItems;
}
currentDirective = new DirectiveHolder(directive, match.match.Groups[2].Value, parser, position++);
holders.Add(currentDirective);
holders = currentDirective.CurrentItems;
break;
}
case PlaceholderType.InDirective:
{
var indirective = match.match.Groups[1].Value;
if (currentDirective == null)
{
throw new Exception($"Incorrect In directive {indirective} outside of any other directives");
}
holders = currentDirective.ApplyInDirective(indirective);
break;
}
case PlaceholderType.DirectiveEnd:
{
if (currentDirective == null)
{
throw new Exception($"End of the directive {match.match.Value} don't fit any directive beginning");
}
while (currentDirective.Directive == "elseif")
{
currentDirective = directives.Pop();
}
if (!currentDirective.Directive.Equals(match.match.Groups[1].Value, StringComparison.InvariantCultureIgnoreCase))
{
throw new Exception($"End of the directive {match.match.Value} don't fit any directive beginning");
}
if (directives.Count > 0)
{
currentDirective = directives.Pop();
holders = currentDirective.CurrentItems;
}
else
{
currentDirective = null;
holders = _placeholders;
}
break;
}
}
}
if (directives.Count > 0)
{
throw new Exception($"Not all directives ({directives.Count}) are closed");
}
_placeholders.Add(new TextHolder(template.Substring(templateIndex), position));
}