package graphql.schema;

import graphql.Internal;

import graphql.PublicApi;

import graphql.language.ScalarTypeDefinition;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import static graphql.Assert.assertNotNull;

import static graphql.Assert.assertValidName;

import static java.util.Collections.emptyList;

/**

* A scalar type is a leaf node in the graphql tree of types. This class allows you to define new scalar types.

*

* <blockquote>

* GraphQL provides a number of built‐in scalars, but type systems can add additional scalars with semantic meaning,

* for example, a GraphQL system could define a scalar called Time which, while serialized as a string, promises to

* conform to ISO‐8601. When querying a field of type Time, you can then rely on the ability to parse the result with an ISO‐8601 parser and use a client‐specific primitive for time.

*

* From the spec : http://facebook.github.io/graphql/#sec-Scalars

* </blockquote>

*

* graphql-java ships with a set of predefined scalar types via {@link graphql.Scalars}

*

* @see graphql.Scalars

*/

public class GraphQLScalarType implements GraphQLType, GraphQLInputType, GraphQLOutputType, GraphQLUnmodifiedType, GraphQLNullableType, GraphQLDirectiveContainer {

private final String name;

private final String description;

private final Coercing coercing;

private final ScalarTypeDefinition definition;

private final List<GraphQLDirective> directives;

@Internal

public GraphQLScalarType(String name, String description, Coercing coercing) {

this(name, description, coercing, emptyList(), null);

}

@Internal

public GraphQLScalarType(String name, String description, Coercing coercing, List<GraphQLDirective> directives, ScalarTypeDefinition definition) {

assertValidName(name);

assertNotNull(coercing, "coercing can't be null");

assertNotNull(directives, "directives can't be null");

this.name = name;

this.description = description;

this.coercing = coercing;

this.definition = definition;

this.directives = directives;

}

public String getName() {

return name;

}

public String getDescription() {

return description;

}

public Coercing getCoercing() {

return coercing;

}

public ScalarTypeDefinition getDefinition() {

return definition;

}

@Override

public List<GraphQLDirective> getDirectives() {

return new ArrayList<>(directives);

}

@Override

public String toString() {

return "GraphQLScalarType{" +

"name='" + name + '\'' +

", description='" + description + '\'' +

", coercing=" + coercing +

'}';

}

public static Builder newScalar() {

return new Builder();

}

@PublicApi

public static class Builder {

private String name;

private String description;

private Coercing coercing;

private ScalarTypeDefinition definition;

private final List<GraphQLDirective> directives = new ArrayList<>();

public Builder name(String name) {

this.name = name;

return this;

}

public Builder description(String description) {

this.description = description;

return this;

}

public Builder definition(ScalarTypeDefinition definition) {

this.definition = definition;

return this;

}

public Builder withDirectives(GraphQLDirective... directives) {

Collections.addAll(this.directives, directives);

return this;

}

public GraphQLScalarType build() {

return new GraphQLScalarType(name, description, coercing, directives, definition);

}

}

}