module.exports = function(app) {
    function toJson(object) {
        let json = {};

        for (let prop in object) {
            let value = object[prop];

            switch (typeof value) {
            case 'object':
                if (value instanceof RegExp)
                    json[prop] = value.source;
                break;
            case 'function':
                json[prop] = value.toString();
                break;
            default:
                json[prop] = value;
            }
        }

        return json;
    }

    app.get('/validations', function(req, res) {
        let json = {};
        let models = app.models;

        for (let modelName in models) {
            let model = models[modelName];
            let validations = model.validations;
            let jsonValidations = {};

            for (let fieldName in validations) {
                let jsonField = [];

                for (let validation of validations[fieldName]) {
                    let options = validation.options;

                    if ((options && options.async) ||
                        (validation.validation == 'custom' && !validation.isExportable))
                        continue;

                    jsonField.push(toJson(validation));
                }

                jsonValidations[fieldName] = jsonField;
            }

            json[modelName] = {
                properties: model.definition.rawProperties,
                validations: jsonValidations
            };
        }

        res.set('Content-Type', 'application/json');
        res.send(JSON.stringify(json));
    });
};