library mustache;

import 'src/mustache_impl.dart' as impl;

/// [Mustache template documentation](http://mustache.github.com/mustache.5.html)

/// Use new Template(source) instead.
@deprecated
Template parse(String source, {bool lenient : false})
  => new Template(source, lenient: lenient);

/// A Template can be efficienctly rendered multiple times with different
/// values.
abstract class Template {

  /// The constructor parses the template source and throws [TemplateException]
  /// if the syntax of the source is invalid.
  /// Tag names may only contain characters a-z, A-Z, 0-9, underscore, and minus,
  /// unless lenient mode is specified.
  factory Template(String source,
      {bool lenient,
       bool htmlEscapeValues,
       String name,
       PartialResolver partialResolver}) = impl.Template.fromSource;
  
  String get name;
  String get source;
  
	/// [values] can be a combination of Map, List, String. Any non-String object
	/// will be converted using toString(). Null values will cause a 
	/// [TemplateException], unless lenient module is enabled.
	String renderString(values);

	/// [values] can be a combination of Map, List, String. Any non-String object
	/// will be converted using toString(). Null values will cause a 
	/// FormatException, unless lenient module is enabled.
	void render(values, StringSink sink);
}


@deprecated
abstract class MustacheFormatException implements FormatException {  
}

typedef Template PartialResolver(String templateName);

typedef Object LambdaFunction(LambdaContext context);

/// Passed as an argument to a mustache lambda function. The methods on
/// this object may only be called before the lambda function returns. If a 
/// method is called after it has returned an exception will be thrown.
abstract class LambdaContext {
  
  /// Render the current section tag in the current context and return the
  /// result as a string. If provided, value will be added to the top of the
  /// context's stack.
  String renderString({Object value});
  
  /// Render and directly output the current section tag. If provided, value
  /// will be added to the top of the context's stack.
  void render({Object value});
  
  /// Output a string. The output will not be html escaped, and will be written
  /// before the output returned from the lambda.
  void write(Object object);
  
  /// Get the unevaluated template source for the current section tag.
  String get source;
  
  /// Evaluate the string as a mustache template using the current context. If
  /// provided, value will be added to the top of the context's stack.
  String renderSource(String source, {Object value});  
  
  /// Lookup the value of a variable in the current context. 
  Object lookup(String variableName);
}

const MustacheMirrorsUsedAnnotation mustache = const MustacheMirrorsUsedAnnotation();

class MustacheMirrorsUsedAnnotation {
  const MustacheMirrorsUsedAnnotation();
}


/// [TemplateException] is used to obtain the line and column numbers
/// of the token which caused parse or render to fail.
abstract class TemplateException implements MustacheFormatException, Exception {
  
  /// A message describing the problem parsing or rendering the template.
  String get message;

  /// The name used to identify the template, as passed to the Template
  /// constructor.
  String get templateName;
  
  /// The 1-based line number of the token where formatting error was found.
  int get line;

  /// The 1-based column number of the token where formatting error was found.
  int get column; 
  
  /// The character offset within the template source.
  int get offset;

  /// The template source.
  String get source;
  
  /// A short source substring of the source at the point the problem occurred
  /// with parsing or rendering.
  String get context;
  
  String toString();
}