var nunjucks = require('nunjucks');
var Immutable = require('immutable');
var Promise = require('../../utils/promise');

describe('TemplateBlock', function() {
    var TemplateBlock = require('../templateBlock');
    var TemplateEngine = require('../templateEngine');

    describe('create', function() {
        pit('must initialize a simple TemplateBlock from a function', function() {
            var templateBlock = TemplateBlock.create('sayhello', function(block) {
                return '<p>Hello, World!</p>';
            });

            // Check basic templateBlock properties
            expect(templateBlock.getName()).toBe('sayhello');
            expect(templateBlock.getPost()).toBeNull();
            expect(templateBlock.getParse()).toBeTruthy();
            expect(templateBlock.getEndTag()).toBe('endsayhello');
            expect(templateBlock.getBlocks().size).toBe(0);
            expect(templateBlock.getShortcuts().size).toBe(0);
            expect(templateBlock.getExtensionName()).toBe('BlocksayhelloExtension');

            // Check result of applying block
            return Promise()
            .then(function() {
                return templateBlock.applyBlock();
            })
            .then(function(result) {
                expect(result.name).toBe('sayhello');
                expect(result.body).toBe('<p>Hello, World!</p>');
            });
        });
    });

    describe('toNunjucksExt()', function() {
        pit('must create a valid nunjucks extension', function() {
            var templateBlock = TemplateBlock.create('sayhello', function(block) {
                return '<p>Hello, World!</p>';
            });

            // Create a fresh Nunjucks environment
            var env = new nunjucks.Environment(null, { autoescape: false });

            // Add template block to environement
            var Ext = templateBlock.toNunjucksExt();
            env.addExtension(templateBlock.getExtensionName(), new Ext());

            // Render a template using the block
            var src = '{% sayhello %}{% endsayhello %}';
            return Promise.nfcall(env.renderString.bind(env), src)
            .then(function(res) {
                expect(res).toBe('<p>Hello, World!</p>');
            });
        });

        pit('must apply block arguments correctly', function() {
            var templateBlock = TemplateBlock.create('sayhello', function(block) {
                return '<'+block.kwargs.tag+'>Hello, '+block.kwargs.name+'!</'+block.kwargs.tag+'>';
            });

            // Create a fresh Nunjucks environment
            var env = new nunjucks.Environment(null, { autoescape: false });

            // Add template block to environement
            var Ext = templateBlock.toNunjucksExt();
            env.addExtension(templateBlock.getExtensionName(), new Ext());

            // Render a template using the block
            var src = '{% sayhello name="Samy", tag="p" %}{% endsayhello %}';
            return Promise.nfcall(env.renderString.bind(env), src)
            .then(function(res) {
                expect(res).toBe('<p>Hello, Samy!</p>');
            });
        });

        pit('must handle nested blocks', function() {
            var templateBlock = new TemplateBlock({
                name: 'yoda',
                blocks: Immutable.List(['start', 'end']),
                process: function(block) {
                    var nested = {};

                    block.blocks.forEach(function(blk) {
                        nested[blk.name] = blk.body.trim();
                    });

                    return '<p class="yoda">'+nested.end+' '+nested.start+'</p>';
                }
            });

            // Create a fresh Nunjucks environment
            var env = new nunjucks.Environment(null, { autoescape: false });

            // Add template block to environement
            var Ext = templateBlock.toNunjucksExt();
            env.addExtension(templateBlock.getExtensionName(), new Ext());

            // Render a template using the block
            var src = '{% yoda %}{% start %}this sentence should be{% end %}inverted{% endyoda %}';
            return Promise.nfcall(env.renderString.bind(env), src)
            .then(function(res) {
                expect(res).toBe('<p class="yoda">inverted this sentence should be</p>');
            });
        });
    });
});