(function umd(root, factory) {
    if (typeof module === 'object' && typeof exports === 'object')
        module.exports = factory()
    else if (typeof define === 'function' && define.amd)
        define([], factory)
    else
        root.httpVueLoader = factory()
})(this, function factory() {
    'use strict';

    var scopeIndex = 0;

    StyleContext.prototype = {

        withBase: function (callback) {

            var tmpBaseElt;
            if (this.component.baseURI) {

                // firefox and chrome need the <base> to be set while inserting or modifying <style> in a document.
                tmpBaseElt = document.createElement('base');
                tmpBaseElt.href = this.component.baseURI;

                var headElt = this.component.getHead();
                headElt.insertBefore(tmpBaseElt, headElt.firstChild);
            }

            callback.call(this);

            if (tmpBaseElt)
                this.component.getHead().removeChild(tmpBaseElt);
        },

        scopeStyles: function (styleElt, scopeName) {

            function process() {

                var sheet = styleElt.sheet;
                var rules = sheet.cssRules;

                for (var i = 0; i < rules.length; ++i) {

                    var rule = rules[i];
                    if (rule.type !== 1)
                        continue;

                    var scopedSelectors = [];

                    rule.selectorText.split(/\s*,\s*/).forEach(function (sel) {

                        scopedSelectors.push(scopeName + ' ' + sel);
                        var segments = sel.match(/([^ :]+)(.+)?/);
                        scopedSelectors.push(segments[1] + scopeName + (segments[2] || ''));
                    });

                    var scopedRule = scopedSelectors.join(',') + rule.cssText.substr(rule.selectorText.length);
                    sheet.deleteRule(i);
                    sheet.insertRule(scopedRule, i);
                }
            }

            try {
                // firefox may fail sheet.cssRules with InvalidAccessError
                process();
            } catch (ex) {

                if (ex instanceof DOMException && ex.code === DOMException.INVALID_ACCESS_ERR) {

                    styleElt.sheet.disabled = true;
                    styleElt.addEventListener('load', function onStyleLoaded() {

                        styleElt.removeEventListener('load', onStyleLoaded);

                        // firefox need this timeout otherwise we have to use document.importNode(style, true)
                        setTimeout(function () {

                            process();
                            styleElt.sheet.disabled = false;
                        });
                    });
                    return;
                }

                throw ex;
            }
        },

        compile: function () {

            var hasTemplate = this.template !== null;

            var scoped = this.elt.hasAttribute('scoped');

            if (scoped) {

                // no template, no scopable style needed
                if (!hasTemplate)
                    return;

                // firefox does not tolerate this attribute
                this.elt.removeAttribute('scoped');
            }

            this.withBase(function () {

                this.component.getHead().appendChild(this.elt);
            });

            if (scoped)
                this.scopeStyles(this.elt, '[' + this.component.getScopeId() + ']');

            return Promise.resolve();
        },

        getContent: function () {

            return this.elt.textContent;
        },

        setContent: function (content) {

            this.withBase(function () {

                this.elt.textContent = content;
            });
        }
    };

    function StyleContext(component, elt) {

        this.component = component;
        this.elt = elt;
    }


    ScriptContext.prototype = {

        getContent: function () {

            return this.elt.textContent;
        },

        setContent: function (content) {

            this.elt.textContent = content;
        },

        compile: function (module) {

            var childModuleRequire = function (childURL) {

                return httpVueLoader.require(resolveURL(this.component.baseURI, childURL));
            }.bind(this);

            var childLoader = function (childURL, childName) {

                return httpVueLoader(resolveURL(this.component.baseURI, childURL), childName);
            }.bind(this);

            try {
                Function('exports', 'require', 'httpVueLoader', 'module', this.getContent()).call(this.module.exports, this.module.exports, childModuleRequire, childLoader, this.module);
            } catch (ex) {

                if (!('lineNumber' in ex)) {

                    return Promise.reject(ex);
                }
                var vueFileData = responseText.replace(/\r?\n/g, '\n');
                var lineNumber = vueFileData.substr(0, vueFileData.indexOf(script)).split('\n').length + ex.lineNumber - 1;
                throw new (ex.constructor)(ex.message, url, lineNumber);
            }

            return Promise.resolve(this.module.exports)
                .then(httpVueLoader.scriptExportsHandler.bind(this))
                .then(function (exports) {

                    this.module.exports = exports;
                }.bind(this));
        }
    };

    function ScriptContext(component, elt) {

        this.component = component;
        this.elt = elt;
        this.module = {exports: {}};
    }


    TemplateContext.prototype = {

        getContent: function () {

            return this.elt.innerHTML;
        },

        setContent: function (content) {

            this.elt.innerHTML = content;
        },

        getRootElt: function () {

            var tplElt = this.elt.content || this.elt;

            if ('firstElementChild' in tplElt)
                return tplElt.firstElementChild;

            for (tplElt = tplElt.firstChild; tplElt !== null; tplElt = tplElt.nextSibling)
                if (tplElt.nodeType === Node.ELEMENT_NODE)
                    return tplElt;

            return null;
        },

        compile: function () {

            return Promise.resolve();
        }
    };

    function TemplateContext(component, elt) {

        this.component = component;
        this.elt = elt;
    }


    Component.prototype = {

        getHead: function () {

            return document.head || document.getElementsByTagName('head')[0];
        },

        getScopeId: function () {

            if (this._scopeId === '') {

                this._scopeId = 'data-s-' + (scopeIndex++).toString(36);
                this.template.getRootElt().setAttribute(this._scopeId, '');
            }
            return this._scopeId;
        },

        load: function (componentURL) {

            return httpVueLoader.httpRequest(componentURL)
                .then(function (responseText) {

                    this.baseURI = componentURL.substr(0, componentURL.lastIndexOf('/') + 1);
                    var doc = document.implementation.createHTMLDocument('');

                    // IE requires the <base> to come with <style>
                    doc.body.innerHTML = (this.baseURI ? '<base href="' + this.baseURI + '">' : '') + responseText;

                    for (var it = doc.body.firstChild; it; it = it.nextSibling) {

                        switch (it.nodeName) {
                            case 'TEMPLATE':
                                this.template = new TemplateContext(this, it);
                                break;
                            case 'SCRIPT':
                                this.script = new ScriptContext(this, it);
                                break;
                            case 'STYLE':
                                this.styles.push(new StyleContext(this, it));
                                break;
                        }
                    }

                    return this;
                }.bind(this));
        },

        _normalizeSection: function (eltCx) {

            var p;

            if (eltCx === null || !eltCx.elt.hasAttribute('src')) {

                p = Promise.resolve(null);
            } else {

                p = httpVueLoader.httpRequest(eltCx.elt.getAttribute('src'))
                    .then(function (content) {

                        eltCx.elt.removeAttribute('src');
                        return content;
                    });
            }

            return p
                .then(function (content) {

                    if (eltCx !== null && eltCx.elt.hasAttribute('lang')) {

                        var lang = eltCx.elt.getAttribute('lang');
                        eltCx.elt.removeAttribute('lang');
                        return httpVueLoader.langProcessor[lang.toLowerCase()].call(this, content === null ? eltCx.getContent() : content);
                    }
                    return content;
                }.bind(this))
                .then(function (content) {

                    if (content !== null)
                        eltCx.setContent(content);
                });
        },

        normalize: function () {

            return Promise.all(Array.prototype.concat(
                this._normalizeSection(this.template),
                this._normalizeSection(this.script),
                this.styles.map(this._normalizeSection)
            ))
                .then(function () {

                    return this;
                }.bind(this));
        },

        compile: function () {

            return Promise.all(Array.prototype.concat(
                this.template && this.template.compile(),
                this.script && this.script.compile(),
                this.styles.map(function (style) {
                    return style.compile();
                })
            ))
                .then(function () {

                    return this;
                }.bind(this));
        }
    };

    function Component(name) {

        this.name = name;
        this.template = null;
        this.script = null;
        this.styles = [];
        this._scopeId = '';
    }

    function identity(value) {

        return value;
    }

    function parseComponentURL(url) {

        var comp = url.match(/(.*?)([^/]+?)\/?(\.vue)?(\?.*|#.*|$)/);
        return {
            name: comp[2],
            url: comp[1] + comp[2] + (comp[3] === undefined ? '/index.vue' : comp[3]) + comp[4]
        };
    }

    function resolveURL(baseURL, url) {

        if (url.substr(0, 2) === './' || url.substr(0, 3) === '../') {
            return baseURL + url;
        }
        return url;
    }


    httpVueLoader.load = function (url, name) {

        return function () {

            return new Component(name).load(url)
                .then(function (component) {

                    return component.normalize();
                })
                .then(function (component) {

                    return component.compile();
                })
                .then(function (component) {

                    var exports = component.script !== null ? component.script.module.exports : {};

                    if (component.template !== null)
                        exports.template = component.template.getContent();

                    if (exports.name === undefined)
                        if (component.name !== undefined)
                            exports.name = component.name;

                    exports._baseURI = component.baseURI;

                    return exports;
                });
        };
    };


    httpVueLoader.register = function (Vue, url) {

        var comp = parseComponentURL(url);
        Vue.component(comp.name, httpVueLoader.load(comp.url));
    };

    httpVueLoader.install = function (Vue) {

        Vue.mixin({

            beforeCreate: function () {

                var components = this.$options.components;

                for (var componentName in components) {

                    if (typeof (components[componentName]) === 'string' && components[componentName].substr(0, 4) === 'url:') {

                        var comp = parseComponentURL(components[componentName].substr(4));

                        var componentURL = ('_baseURI' in this.$options) ? resolveURL(this.$options._baseURI, comp.url) : comp.url;

                        if (isNaN(componentName))
                            components[componentName] = httpVueLoader.load(componentURL, componentName);
                        else
                            components[componentName] = Vue.component(comp.name, httpVueLoader.load(componentURL, comp.name));
                    }
                }
            }
        });
    };

    httpVueLoader.require = function (moduleName) {

        return window[moduleName];
    };

    httpVueLoader.httpRequest = function (url) {

        return new Promise(function (resolve, reject) {

            var xhr = new XMLHttpRequest();
            xhr.open('GET', url);
            xhr.responseType = 'text';

            xhr.onreadystatechange = function () {

                if (xhr.readyState === 4) {

                    if (xhr.status >= 200 && xhr.status < 300)
                        resolve(xhr.responseText);
                    else
                        reject(xhr.status);
                }
            };

            xhr.send(null);
        });
    };

    httpVueLoader.langProcessor = {
        html: identity,
        js: identity,
        css: identity
    };

    httpVueLoader.scriptExportsHandler = identity;

    function httpVueLoader(url, name) {

        var comp = parseComponentURL(url);
        return httpVueLoader.load(comp.url, name);
    }

    return httpVueLoader;
});