/** @module validate */
import { IValidationRule } from './IValidationRule';
import { ValidationResult } from './ValidationResult';
import { ValidationResultType } from './ValidationResultType';
import { Schema } from './Schema';
import { PropertySchema } from './PropertySchema';
import { ObjectComparator } from './ObjectComparator';
import { ObjectReader } from '../reflect/ObjectReader';

/**
 * Schema to validate user defined objects.
 * 
 * ### Example ###
 * 
 *     let schema = new ObjectSchema(false)
 *         .withOptionalProperty("id", TypeCode.String)
 *         .withRequiredProperty("name", TypeCode.String);
 *     
 *     schema.validate({ id: "1", name: "ABC" });       // Result: no errors
 *     schema.validate({ name: "ABC" });                // Result: no errors
 *     schema.validate({ id: 1, name: "ABC" });         // Result: id type mismatch
 *     schema.validate({ id: 1, _name: "ABC" });        // Result: name is missing, unexpected _name
 *     schema.validate("ABC");                          // Result: type mismatch
 */
export class ObjectSchema extends Schema {
    private _properties: PropertySchema[];
    private _allowUndefined: boolean;

    /**
     * Creates a new validation schema and sets its values. 
     * 
     * @param allowUndefined    true to allow properties undefines in the schema
     * @param required          (optional) true to always require non-null values.
     * @param rules             (optional) a list with validation rules.
     * 
     * @see [[IValidationRule]]
     */
    public constructor(allowUndefined?: boolean, required?: boolean, rules?: IValidationRule[]) {
        super(required, rules);
        this._allowUndefined = allowUndefined;
    }

    /**
     * Gets validation schemas for object properties.
     * 
     * @returns the list of property validation schemas.
     * 
     * @see [[PropertySchema]]
     */
    public getProperties(): PropertySchema[] {
        return this._properties;
    }

    /**
     * Sets validation schemas for object properties.
     * 
     * @param value     a list of property validation schemas.
     * 
     * @see [[PropertySchema]]
     */
    public setProperties(value: PropertySchema[]) {
        this._properties = value;
    }

    /**
     * Gets flag to allow undefined properties
     * 
     * @returns true to allow undefined properties and false to disallow.
     */
    public get isUndefinedAllowed(): boolean {
        return this._allowUndefined;
    }

    /**
     * Sets flag to allow undefined properties
     * 
     * @param value     true to allow undefined properties and false to disallow.
     */
    public set isUndefinedAllowed(value: boolean) {
        this._allowUndefined = value;
    }

    /**
     * Sets flag to allow undefined properties
     * 
     * This method returns reference to this exception to implement Builder pattern
     * to chain additional calls.
     * 
     * @param value     true to allow undefined properties and false to disallow.
     * @returns this validation schema.
     */
    public allowUndefined(value: boolean): ObjectSchema {
        this.isUndefinedAllowed = value;
        return this;
    }

    /**
     * Adds a validation schema for an object property.
     * 
     * This method returns reference to this exception to implement Builder pattern
     * to chain additional calls.
     * 
     * @param schema    a property validation schema to be added.
     * @returns this validation schema.
     * 
     * @see [[PropertySchema]]
     */
    public withProperty(schema: PropertySchema): ObjectSchema {
        this._properties = this._properties || [];
        this._properties.push(schema);
        return this;
    }

    /**
     * Adds a validation schema for a required object property.
     * 
     * @param name      a property name.
     * @param type      (optional) a property schema or type.
     * @param rules     (optional) a list of property validation rules.
     */
    public withRequiredProperty(name: string, type?: any, ...rules: IValidationRule[]): ObjectSchema {
        var schema = new PropertySchema(name, type);
        schema.setRules(rules.slice());
        schema.makeRequired();

        return this.withProperty(schema);
    }

    /**
     * Adds a validation schema for an optional object property.
     * 
     * @param name      a property name.
     * @param type      (optional) a property schema or type.
     * @param rules     (optional) a list of property validation rules.
     */
    public withOptionalProperty(name: string, type?: any, ...rules: IValidationRule[]): ObjectSchema {
        var schema = new PropertySchema(name, type);
        schema.setRules(rules.slice());
        schema.makeOptional();

        return this.withProperty(schema);
    }

    /**
     * Validates a given value against the schema and configured validation rules.
     * 
     * @param path      a dot notation path to the value.
     * @param value     a value to be validated.
     * @param results   a list with validation results to add new results.
     */
    protected performValidation(path: string, value: any, results: ValidationResult[]): void {
        super.performValidation(path, value, results);

        if (!value) return;

        let name = path || "value";
        let properties = ObjectReader.getProperties(value);

        if (this._properties) {
            for (var i = 0; i < this._properties.length; i++) {
                var propertySchema: PropertySchema = this._properties[i];
                var processedName = null;

                for (var key in properties) {
                    var propertyName = key;
                    var propertyValue = properties[key];

                    if (ObjectComparator.areEqual(propertySchema.getName(), propertyName)) {
                        propertySchema.performValidation(path, propertyValue, results);
                        processedName = propertyName;
                        break;
                    }
                }

                if (processedName)
                    delete properties[processedName];
                else
                    propertySchema.performValidation(path, null, results);
            }
        }

        if (!this._allowUndefined)
            for (var key in properties) {
                let propertyPath: string = key && path != "" ? path + "." + key : key;

                results.push(new ValidationResult(
                    propertyPath,
                    ValidationResultType.Warning,
                    "UNEXPECTED_PROPERTY",
                    name + " contains unexpected property " + key,
                    null,
                    key
                ));
            }
    }

}