private CodeCompletionSettings GetCodeCompletionSettingsForPosition(string source, int position, Configuration codeAssistanceConfiguration)
{
var parser = new Parser();
var parseResult = parser.Parse(source);
var filter = GetFilterSegment(parseResult.Tokens, position);
var settings = new CodeCompletionSettings
{
CompletionData = GetCodeCompletionForExpression(parseResult.Tree.FindExpressionAt(position), codeAssistanceConfiguration, source.Substring(filter.Offset, filter.Length)),
IdentifierSegment = filter
};
return settings;
}
private IEnumerable<ICompletionData> GetCodeCompletionForContext(IList<string> currentContext, Configuration codeAssistanceConfiguration, string filter)
{
var completion = new List<ICompletionData>();
var matches = GetMatches(currentContext, codeAssistanceConfiguration);
if (matches != null)
{
foreach (var match in matches)
{
completion.AddRange(GetFunctionCompletionData(match.IntrinsicFunctions));
completion.AddRange(GetKeywordCompletionData(match.Keywords));
}
var result = completion.AsQueryable();
if (!string.IsNullOrWhiteSpace(filter)) result = result.Where(c => c.Text.StartsWith(filter));
return result.OrderBy(c => c.Text);
}
return completion;
}
private IEnumerable<ICompletionData> GetCodeCompletionForExpression(Expression expression, Configuration codeAssistanceConfiguration, string filter)
{
var context = GetExpressionContext(expression);
return GetCodeCompletionForContext(context, codeAssistanceConfiguration, filter);
}
/// <summary>
/// Finds all codecompletions from the configuration that match the current context. multiple matches with the same score are all returned.
/// </summary>
/// <param name="currentContext"></param>
/// <param name="codeAssistanceConfiguration"></param>
/// <returns></returns>
private List<Context> GetMatches(IList<string> currentContext, Configuration codeAssistanceConfiguration)
{
var currentScore = int.MaxValue;
List<Context> matches = null;
foreach (var context in codeAssistanceConfiguration.Contexts)
{
var score = GetMatchScore(currentContext, context.ContextExpression.ToLower().Split('.'));
if (score.HasValue)
{
if (score.Value < currentScore)
{
matches = new List<Context> { context };
currentScore = score.Value;
}
else if (score.Value == currentScore)
{
matches.Add(context);
}
}
}
return matches;
}
