/**
Virtual rollup of the `template-base` and `template-micro` modules.

@module template
@main template
@since 3.8.0
**/

/**
Provides a generic API for using template engines such as Handlebars and
`Y.Template.Micro`.

@module template
@submodule template-base
@since 3.8.0
**/

/**
Provides a generic API for using template engines such as Handlebars and
`Y.Template.Micro`.

### Examples

Using with `Y.Template.Micro` (the default template engine):

    YUI().use('template', function (Y) {
        var micro = new Y.Template(),
            html  = micro.render('<%= data.message %>', {message: 'hello!'});

        // ...
    });

Using with Handlebars:

    YUI().use('template-base', 'handlebars', function (Y) {
        var handlebars = new Y.Template(Y.Handlebars),
            html       = handlebars.render('{{message}}', {message: 'hello!'});

        // ...
    });

@class Template
@param {Mixed} [engine=Y.Template.Micro] Template engine to use, such as
    `Y.Template.Micro` or `Y.Handlebars`. Defaults to `Y.Template.Micro` if not
    specified.
@constructor
@since 3.8.0
**/

function Template(engine) {
    /**
    Template engine class.

    @property {Mixed} engine
    @since 3.8.0
    **/
    this.engine = engine || Y.Template.Micro;

    if (!this.engine) {
        Y.error('No template engine loaded.');
    }
}

Template.prototype = {
    /**
    Compiles a template with the current template engine and returns a compiled
    template function.

    @method compile
    @param {String} text Template text to compile.
    @param {Object} [options] Options to pass along to the template engine. See
        template engine docs for options supported by each engine.
    @return {Function} Compiled template function.
    @since 3.8.0
    **/
    compile: function (text, options) {
        return this.engine.compile(text, options);
    },

    /**
    Precompiles a template with the current template engine and returns a string
    containing JavaScript source code for the precompiled template.

    @method precompile
    @param {String} text Template text to compile.
    @param {Object} [options] Options to pass along to the template engine. See
        template engine docs for options supported by each engine.
    @return {String} Source code for the precompiled template.
    @since 3.8.0
    **/
    precompile: function (text, options) {
        return this.engine.precompile(text, options);
    },

    /**
    Compiles and renders a template with the current template engine in a single
    step, and returns the rendered result.

    @method render
    @param {String} text Template text to render.
    @param {Object} data Data object to provide when rendering the template.
    @param {Object} [options] Options to pass along to the template engine. See
        template engine docs for options supported by each engine.
    @return {String} Rendered result.
    @since 3.8.0
    **/
    render: function (text, data, options) {
        if (this.engine.render) {
            return this.engine.render(text, data, options);
        }

        return this.engine.compile(text, options)(data, options);
    },

    /**
    Revives a precompiled template function into an executable template function
    using the current template engine. The precompiled code must already have
    been evaluated; this method won't evaluate it for you.

    @method revive
    @param {Function} precompiled Precompiled template function.
    @param {Object} [options] Options to pass along to the template engine. See
        template engine docs for options supported by each engine.
    @return {Function} Compiled template function.
    @since 3.8.0
    **/
    revive: function (precompiled, options) {
        return this.engine.revive ? this.engine.revive(precompiled, options) :
                precompiled;
    }
};

// Copy existing namespaced properties from Y.Template to the Template function
// if Y.Template already exists, then make the function the new Y.Template.
// This ensures that other modules can safely add stuff to the Y.Template
// namespace even if they're loaded before this one.
Y.Template = Y.Template ? Y.mix(Template, Y.Template) : Template;