/*global window, XMLHttpRequest */

module.exports = function(options, logger) {

    var AbstractFileManager = require("../less/environment/abstract-file-manager.js");

    var fileCache = {};

    //TODOS - move log somewhere. pathDiff and doing something similar in node. use pathDiff in the other browser file for the initial load

    function getXMLHttpRequest() {
        if (window.XMLHttpRequest && (window.location.protocol !== "file:" || !("ActiveXObject" in window))) {
            return new XMLHttpRequest();
        } else {
            try {
                /*global ActiveXObject */
                return new ActiveXObject("Microsoft.XMLHTTP");
            } catch (e) {
                logger.error("browser doesn't support AJAX.");
                return null;
            }
        }
    }

    var FileManager = function() {
    };

    FileManager.prototype = new AbstractFileManager();

    FileManager.prototype.alwaysMakePathsAbsolute = function alwaysMakePathsAbsolute() {
        return true;
    };
    FileManager.prototype.join = function join(basePath, laterPath) {
        if (!basePath) {
            return laterPath;
        }
        return this.extractUrlParts(laterPath, basePath).path;
    };
    FileManager.prototype.doXHR = function doXHR(url, type, callback, errback) {

        var xhr = getXMLHttpRequest();
        var async = options.isFileProtocol ? options.fileAsync : options.async;

        if (typeof xhr.overrideMimeType === 'function') {
            xhr.overrideMimeType('text/css');
        }
        logger.debug("XHR: Getting '" + url + "'");
        xhr.open('GET', url, async);
        xhr.setRequestHeader('Accept', type || 'text/x-less, text/css; q=0.9, */*; q=0.5');
        xhr.send(null);

        function handleResponse(xhr, callback, errback) {
            if (xhr.status >= 200 && xhr.status < 300) {
                callback(xhr.responseText,
                    xhr.getResponseHeader("Last-Modified"));
            } else if (typeof errback === 'function') {
                errback(xhr.status, url);
            }
        }

        if (options.isFileProtocol && !options.fileAsync) {
            if (xhr.status === 0 || (xhr.status >= 200 && xhr.status < 300)) {
                callback(xhr.responseText);
            } else {
                errback(xhr.status, url);
            }
        } else if (async) {
            xhr.onreadystatechange = function () {
                if (xhr.readyState == 4) {
                    handleResponse(xhr, callback, errback);
                }
            };
        } else {
            handleResponse(xhr, callback, errback);
        }
    };
    FileManager.prototype.supports = function(filename, currentDirectory, options, environment) {
        return true;
    };

    FileManager.prototype.clearFileCache = function() {
        fileCache = {};
    };

    FileManager.prototype.loadFile = function loadFile(filename, currentDirectory, options, environment, callback) {
        if (currentDirectory && !this.isPathAbsolute(filename)) {
            filename = currentDirectory + filename;
        }

        options = options || {};

        // sheet may be set to the stylesheet for the initial load or a collection of properties including
        // some context variables for imports
        var hrefParts = this.extractUrlParts(filename, window.location.href);
        var href      = hrefParts.url;

        if (options.useFileCache && fileCache[href]) {
            try {
                var lessText = fileCache[href];
                callback(null, { contents: lessText, filename: href, webInfo: { lastModified: new Date() }});
            } catch (e) {
                callback({filename: href, message: "Error loading file " + href + " error was " + e.message});
            }
            return;
        }

        this.doXHR(href, options.mime, function doXHRCallback(data, lastModified) {
            // per file cache
            fileCache[href] = data;

            // Use remote copy (re-parse)
            callback(null, { contents: data, filename: href, webInfo: { lastModified: lastModified }});
        }, function doXHRError(status, url) {
            callback({ type: 'File', message: "'" + url + "' wasn't found (" + status + ")", href: href });
        });
    };

    return FileManager;
};
