wekan/packages/wekan-cfs-data-man/client/Blob.js

/* Blob.js
 * A Blob implementation.
 * 2013-12-27
 *
 * By Eli Grey, http://eligrey.com
 * By Devin Samarin, https://github.com/eboyjr
 * License: X11/MIT
 *   See LICENSE.md
 */

/*global self, unescape */
/*jslint bitwise: true, regexp: true, confusion: true, es5: true, vars: true, white: true,
  plusplus: true */

/*! @source http://purl.eligrey.com/github/Blob.js/blob/master/Blob.js */

if (!(typeof Blob === "function" || typeof Blob === "object") || typeof URL === "undefined")
if ((typeof Blob === "function" || typeof Blob === "object") && typeof webkitURL !== "undefined") self.URL = webkitURL;
else var Blob = (function (view) {
    "use strict";

    var BlobBuilder = view.BlobBuilder || view.WebKitBlobBuilder || view.MozBlobBuilder || view.MSBlobBuilder || (function(view) {
        var
              get_class = function(object) {
                return Object.prototype.toString.call(object).match(/^\[object\s(.*)\]$/)[1];
            }
            , FakeBlobBuilder = function BlobBuilder() {
                this.data = [];
            }
            , FakeBlob = function Blob(data, type, encoding) {
                this.data = data;
                this.size = data.length;
                this.type = type;
                this.encoding = encoding;
            }
            , FBB_proto = FakeBlobBuilder.prototype
            , FB_proto = FakeBlob.prototype
            , FileReaderSync = view.FileReaderSync
            , FileException = function(type) {
                this.code = this[this.name = type];
            }
            , file_ex_codes = (
                  "NOT_FOUND_ERR SECURITY_ERR ABORT_ERR NOT_READABLE_ERR ENCODING_ERR "
                + "NO_MODIFICATION_ALLOWED_ERR INVALID_STATE_ERR SYNTAX_ERR"
            ).split(" ")
            , file_ex_code = file_ex_codes.length
            , real_URL = view.URL || view.webkitURL || view
            , real_create_object_URL = real_URL.createObjectURL
            , real_revoke_object_URL = real_URL.revokeObjectURL
            , URL = real_URL
            , btoa = view.btoa
            , atob = view.atob

            , ArrayBuffer = view.ArrayBuffer
            , Uint8Array = view.Uint8Array
        ;
        FakeBlob.fake = FB_proto.fake = true;
        while (file_ex_code--) {
            FileException.prototype[file_ex_codes[file_ex_code]] = file_ex_code + 1;
        }
        if (!real_URL.createObjectURL) {
            URL = view.URL = {};
        }
        URL.createObjectURL = function(blob) {
            var
                  type = blob.type
                , data_URI_header
            ;
            if (type === null) {
                type = "application/octet-stream";
            }
            if (blob instanceof FakeBlob) {
                data_URI_header = "data:" + type;
                if (blob.encoding === "base64") {
                    return data_URI_header + ";base64," + blob.data;
                } else if (blob.encoding === "URI") {
                    return data_URI_header + "," + decodeURIComponent(blob.data);
                } if (btoa) {
                    return data_URI_header + ";base64," + btoa(blob.data);
                } else {
                    return data_URI_header + "," + encodeURIComponent(blob.data);
                }
            } else if (real_create_object_URL) {
                return real_create_object_URL.call(real_URL, blob);
            }
        };
        URL.revokeObjectURL = function(object_URL) {
            if (object_URL.substring(0, 5) !== "data:" && real_revoke_object_URL) {
                real_revoke_object_URL.call(real_URL, object_URL);
            }
        };
        FBB_proto.append = function(data/*, endings*/) {
            var bb = this.data;
            // decode data to a binary string
            if (Uint8Array && (data instanceof ArrayBuffer || data instanceof Uint8Array)) {
                var
                      str = ""
                    , buf = new Uint8Array(data)
                    , i = 0
                    , buf_len = buf.length
                ;
                for (; i < buf_len; i++) {
                    str += String.fromCharCode(buf[i]);
                }
                bb.push(str);
            } else if (get_class(data) === "Blob" || get_class(data) === "File") {
                if (FileReaderSync) {
                    var fr = new FileReaderSync;
                    bb.push(fr.readAsBinaryString(data));
                } else {
                    // async FileReader won't work as BlobBuilder is sync
                    throw new FileException("NOT_READABLE_ERR");
                }
            } else if (data instanceof FakeBlob) {
                if (data.encoding === "base64" && atob) {
                    bb.push(atob(data.data));
                } else if (data.encoding === "URI") {
                    bb.push(decodeURIComponent(data.data));
                } else if (data.encoding === "raw") {
                    bb.push(data.data);
                }
            } else {
                if (typeof data !== "string") {
                    data += ""; // convert unsupported types to strings
                }
                // decode UTF-16 to binary string
                bb.push(unescape(encodeURIComponent(data)));
            }
        };
        FBB_proto.getBlob = function(type) {
            if (!arguments.length) {
                type = null;
            }
            return new FakeBlob(this.data.join(""), type, "raw");
        };
        FBB_proto.toString = function() {
            return "[object BlobBuilder]";
        };
        FB_proto.slice = function(start, end, type) {
            var args = arguments.length;
            if (args < 3) {
                type = null;
            }
            return new FakeBlob(
                  this.data.slice(start, args > 1 ? end : this.data.length)
                , type
                , this.encoding
            );
        };
        FB_proto.toString = function() {
            return "[object Blob]";
        };
        return FakeBlobBuilder;
    }(view));

    return function Blob(blobParts, options) {
        var type = options ? (options.type || "") : "";
        var builder = new BlobBuilder();
        if (blobParts) {
            for (var i = 0, len = blobParts.length; i < len; i++) {
                builder.append(blobParts[i]);
            }
        }
        return builder.getBlob(type);
    };
}(typeof self !== "undefined" && self || typeof window !== "undefined" && window || this.content || this));