gecko/toolkit/mozapps/downloads/DownloadUtils.jsm

516 lines
17 KiB
JavaScript

/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Download Manager Utility Code.
*
* The Initial Developer of the Original Code is
* Edward Lee <edward.lee@engineering.uiuc.edu>.
* Portions created by the Initial Developer are Copyright (C) 2008
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
var EXPORTED_SYMBOLS = [ "DownloadUtils" ];
/**
* This module provides the DownloadUtils object which contains useful methods
* for downloads such as displaying file sizes, transfer times, and download
* locations.
*
* List of methods:
*
* [string status, double newLast]
* getDownloadStatus(int aCurrBytes, [optional] int aMaxBytes,
* [optional] double aSpeed, [optional] double aLastSec)
*
* string progress
* getTransferTotal(int aCurrBytes, [optional] int aMaxBytes)
*
* [string timeLeft, double newLast]
* getTimeLeft(double aSeconds, [optional] double aLastSec)
*
* [string displayHost, string fullHost]
* getURIHost(string aURIString)
*
* [string convertedBytes, string units]
* convertByteUnits(int aBytes)
*
* [int time, string units, int subTime, string subUnits]
* convertTimeUnits(double aSecs)
*/
const Cc = Components.classes;
const Ci = Components.interfaces;
const Cu = Components.utils;
__defineGetter__("PluralForm", function() {
delete this.PluralForm;
Cu.import("resource://gre/modules/PluralForm.jsm");
return PluralForm;
});
__defineGetter__("gDecimalSymbol", function() {
delete this.gDecimalSymbol;
return this.gDecimalSymbol = Number(5.4).toLocaleString().match(/\D/);
});
const kDownloadProperties =
"chrome://mozapps/locale/downloads/downloads.properties";
// These strings will be converted to the corresponding ones from the string
// bundle on use
let kStrings = {
statusFormat: "statusFormat2",
transferSameUnits: "transferSameUnits",
transferDiffUnits: "transferDiffUnits",
transferNoTotal: "transferNoTotal",
timePair: "timePair",
timeLeftSingle: "timeLeftSingle",
timeLeftDouble: "timeLeftDouble",
timeFewSeconds: "timeFewSeconds",
timeUnknown: "timeUnknown",
doneScheme: "doneScheme",
doneFileScheme: "doneFileScheme",
units: ["bytes", "kilobyte", "megabyte", "gigabyte"],
// Update timeSize in convertTimeUnits if changing the length of this array
timeUnits: ["seconds", "minutes", "hours", "days"],
};
// This object will lazily load the strings defined in kStrings
let gStr = {
/**
* Initialize lazy string getters
*/
_init: function()
{
// Make each "name" a lazy-loading string that knows how to load itself. We
// need to locally scope name and value to keep them around for the getter.
for (let [name, value] in Iterator(kStrings))
let ([n, v] = [name, value])
gStr.__defineGetter__(n, function() gStr._getStr(n, v));
},
/**
* Convert strings to those in the string bundle. This lazily loads the
* string bundle *once* only when used the first time.
*/
get _getStr()
{
// Delete the getter to be overwritten
delete gStr._getStr;
// Lazily load the bundle into the closure on first call to _getStr
let getStr = Cc["@mozilla.org/intl/stringbundle;1"].
getService(Ci.nsIStringBundleService).
createBundle(kDownloadProperties).
GetStringFromName;
// _getStr is a function that sets string "name" to stringbundle's "value"
return gStr._getStr = function(name, value) {
// Delete the getter to be overwritten
delete gStr[name];
try {
// "name" is a string or array of the stringbundle-loaded "value"
return gStr[name] = typeof value == "string" ?
getStr(value) :
value.map(getStr);
} catch (e) {
log(["Couldn't get string '", name, "' from property '", value, "'"]);
// Don't return anything (undefined), and because we deleted ourselves,
// future accesses will also be undefined
}
};
},
};
// Initialize the lazy string getters!
gStr._init();
// Keep track of at most this many second/lastSec pairs so that multiple calls
// to getTimeLeft produce the same time left
const kCachedLastMaxSize = 10;
let gCachedLast = [];
let DownloadUtils = {
/**
* Generate a full status string for a download given its current progress,
* total size, speed, last time remaining
*
* @param aCurrBytes
* Number of bytes transferred so far
* @param [optional] aMaxBytes
* Total number of bytes or -1 for unknown
* @param [optional] aSpeed
* Current transfer rate in bytes/sec or -1 for unknown
* @param [optional] aLastSec
* Last time remaining in seconds or Infinity for unknown
* @return A pair: [download status text, new value of "last seconds"]
*/
getDownloadStatus: function DU_getDownloadStatus(aCurrBytes, aMaxBytes,
aSpeed, aLastSec)
{
if (aMaxBytes == null)
aMaxBytes = -1;
if (aSpeed == null)
aSpeed = -1;
if (aLastSec == null)
aLastSec = Infinity;
// Calculate the time remaining if we have valid values
let seconds = (aSpeed > 0) && (aMaxBytes > 0) ?
(aMaxBytes - aCurrBytes) / aSpeed : -1;
// Update the bytes transferred and bytes total
let status;
let (transfer = DownloadUtils.getTransferTotal(aCurrBytes, aMaxBytes)) {
// Insert 1 is the download progress
status = replaceInsert(gStr.statusFormat, 1, transfer);
}
// Update the download rate
let ([rate, unit] = DownloadUtils.convertByteUnits(aSpeed)) {
// Insert 2 is the download rate
status = replaceInsert(status, 2, rate);
// Insert 3 is the |unit|/sec
status = replaceInsert(status, 3, unit);
}
// Update time remaining
let ([timeLeft, newLast] = DownloadUtils.getTimeLeft(seconds, aLastSec)) {
// Insert 4 is the time remaining
status = replaceInsert(status, 4, timeLeft);
return [status, newLast];
}
},
/**
* Generate the transfer progress string to show the current and total byte
* size. Byte units will be as large as possible and the same units for
* current and max will be suppressed for the former.
*
* @param aCurrBytes
* Number of bytes transferred so far
* @param [optional] aMaxBytes
* Total number of bytes or -1 for unknown
* @return The transfer progress text
*/
getTransferTotal: function DU_getTransferTotal(aCurrBytes, aMaxBytes)
{
if (aMaxBytes == null)
aMaxBytes = -1;
let [progress, progressUnits] = DownloadUtils.convertByteUnits(aCurrBytes);
let [total, totalUnits] = DownloadUtils.convertByteUnits(aMaxBytes);
// Figure out which byte progress string to display
let transfer;
if (aMaxBytes < 0)
transfer = gStr.transferNoTotal;
else if (progressUnits == totalUnits)
transfer = gStr.transferSameUnits;
else
transfer = gStr.transferDiffUnits;
transfer = replaceInsert(transfer, 1, progress);
transfer = replaceInsert(transfer, 2, progressUnits);
transfer = replaceInsert(transfer, 3, total);
transfer = replaceInsert(transfer, 4, totalUnits);
return transfer;
},
/**
* Generate a "time left" string given an estimate on the time left and the
* last time. The extra time is used to give a better estimate on the time to
* show. Both the time values are doubles instead of integers to help get
* sub-second accuracy for current and future estimates.
*
* @param aSeconds
* Current estimate on number of seconds left for the download
* @param [optional] aLastSec
* Last time remaining in seconds or Infinity for unknown
* @return A pair: [time left text, new value of "last seconds"]
*/
getTimeLeft: function DU_getTimeLeft(aSeconds, aLastSec)
{
if (aLastSec == null)
aLastSec = Infinity;
if (aSeconds < 0)
return [gStr.timeUnknown, aLastSec];
// Try to find a cached lastSec for the given second
aLastSec = gCachedLast.reduce(function(aResult, aItem)
aItem[0] == aSeconds ? aItem[1] : aResult, aLastSec);
// Add the current second/lastSec pair unless we have too many
gCachedLast.push([aSeconds, aLastSec]);
if (gCachedLast.length > kCachedLastMaxSize)
gCachedLast.shift();
// Apply smoothing only if the new time isn't a huge change -- e.g., if the
// new time is more than half the previous time; this is useful for
// downloads that start/resume slowly
if (aSeconds > aLastSec / 2) {
// Apply hysteresis to favor downward over upward swings
// 30% of down and 10% of up (exponential smoothing)
let (diff = aSeconds - aLastSec) {
aSeconds = aLastSec + (diff < 0 ? .3 : .1) * diff;
}
// If the new time is similar, reuse something close to the last seconds,
// but subtract a little to provide forward progress
let diff = aSeconds - aLastSec;
let diffPct = diff / aLastSec * 100;
if (Math.abs(diff) < 5 || Math.abs(diffPct) < 5)
aSeconds = aLastSec - (diff < 0 ? .4 : .2);
}
// Decide what text to show for the time
let timeLeft;
if (aSeconds < 4) {
// Be friendly in the last few seconds
timeLeft = gStr.timeFewSeconds;
} else {
// Convert the seconds into its two largest units to display
let [time1, unit1, time2, unit2] =
DownloadUtils.convertTimeUnits(aSeconds);
let pair1 = replaceInsert(gStr.timePair, 1, time1);
pair1 = replaceInsert(pair1, 2, unit1);
let pair2 = replaceInsert(gStr.timePair, 1, time2);
pair2 = replaceInsert(pair2, 2, unit2);
// Only show minutes for under 1 hour unless there's a few minutes left;
// or the second pair is 0.
if ((aSeconds < 3600 && time1 >= 4) || time2 == 0) {
timeLeft = replaceInsert(gStr.timeLeftSingle, 1, pair1);
} else {
// We've got 2 pairs of times to display
timeLeft = replaceInsert(gStr.timeLeftDouble, 1, pair1);
timeLeft = replaceInsert(timeLeft, 2, pair2);
}
}
return [timeLeft, aSeconds];
},
/**
* Get the appropriate display host string for a URI string depending on if
* the URI has an eTLD + 1, is an IP address, a local file, or other protocol
*
* @param aURIString
* The URI string to try getting an eTLD + 1, etc.
* @return A pair: [display host for the URI string, full host name]
*/
getURIHost: function DU_getURIHost(aURIString)
{
let ioService = Cc["@mozilla.org/network/io-service;1"].
getService(Ci.nsIIOService);
let eTLDService = Cc["@mozilla.org/network/effective-tld-service;1"].
getService(Ci.nsIEffectiveTLDService);
let idnService = Cc["@mozilla.org/network/idn-service;1"].
getService(Ci.nsIIDNService);
// Get a URI that knows about its components
let uri = ioService.newURI(aURIString, null, null);
// Get the inner-most uri for schemes like jar:
if (uri instanceof Ci.nsINestedURI)
uri = uri.innermostURI;
let fullHost;
try {
// Get the full host name; some special URIs fail (data: jar:)
fullHost = uri.host;
} catch (e) {
fullHost = "";
}
let displayHost;
try {
// This might fail if it's an IP address or doesn't have more than 1 part
let baseDomain = eTLDService.getBaseDomain(uri);
// Convert base domain for display; ignore the isAscii out param
displayHost = idnService.convertToDisplayIDN(baseDomain, {});
} catch (e) {
// Default to the host name
displayHost = fullHost;
}
// Check if we need to show something else for the host
if (uri.scheme == "file") {
// Display special text for file protocol
displayHost = gStr.doneFileScheme;
fullHost = displayHost;
} else if (displayHost.length == 0) {
// Got nothing; show the scheme (data: about: moz-icon:)
displayHost = replaceInsert(gStr.doneScheme, 1, uri.scheme);
fullHost = displayHost;
} else if (uri.port != -1) {
// Tack on the port if it's not the default port
let port = ":" + uri.port;
displayHost += port;
fullHost += port;
}
return [displayHost, fullHost];
},
/**
* Converts a number of bytes to the appropriate unit that results in an
* internationalized number that needs fewer than 4 digits.
*
* @param aBytes
* Number of bytes to convert
* @return A pair: [new value with 3 sig. figs., its unit]
*/
convertByteUnits: function DU_convertByteUnits(aBytes)
{
let unitIndex = 0;
// Convert to next unit if it needs 4 digits (after rounding), but only if
// we know the name of the next unit
while ((aBytes >= 999.5) && (unitIndex < gStr.units.length - 1)) {
aBytes /= 1024;
unitIndex++;
}
// Get rid of insignificant bits by truncating to 1 or 0 decimal points
// 0 -> 0; 1.2 -> 1.2; 12.3 -> 12.3; 123.4 -> 123; 234.5 -> 235
aBytes = aBytes.toFixed((aBytes > 0) && (aBytes < 100) ? 1 : 0);
if (gDecimalSymbol != ".")
aBytes = aBytes.replace(".", gDecimalSymbol);
return [aBytes, gStr.units[unitIndex]];
},
/**
* Converts a number of seconds to the two largest units. Time values are
* whole numbers, and units have the correct plural/singular form.
*
* @param aSecs
* Seconds to convert into the appropriate 2 units
* @return 4-item array [first value, its unit, second value, its unit]
*/
convertTimeUnits: function DU_convertTimeUnits(aSecs)
{
// These are the maximum values for seconds, minutes, hours corresponding
// with gStr.timeUnits without the last item
let timeSize = [60, 60, 24];
let time = aSecs;
let scale = 1;
let unitIndex = 0;
// Keep converting to the next unit while we have units left and the
// current one isn't the largest unit possible
while ((unitIndex < timeSize.length) && (time >= timeSize[unitIndex])) {
time /= timeSize[unitIndex];
scale *= timeSize[unitIndex];
unitIndex++;
}
let value = convertTimeUnitsValue(time);
let units = convertTimeUnitsUnits(value, unitIndex);
let extra = aSecs - value * scale;
let nextIndex = unitIndex - 1;
// Convert the extra time to the next largest unit
for (let index = 0; index < nextIndex; index++)
extra /= timeSize[index];
let value2 = convertTimeUnitsValue(extra);
let units2 = convertTimeUnitsUnits(value2, nextIndex);
return [value, units, value2, units2];
},
};
/**
* Private helper for convertTimeUnits that gets the display value of a time
*
* @param aTime
* Time value for display
* @return An integer value for the time rounded down
*/
function convertTimeUnitsValue(aTime)
{
return Math.floor(aTime);
}
/**
* Private helper for convertTimeUnits that gets the display units of a time
*
* @param aTime
* Time value for display
* @param aIndex
* Index into gStr.timeUnits for the appropriate unit
* @return The appropriate plural form of the unit for the time
*/
function convertTimeUnitsUnits(aTime, aIndex)
{
// Negative index would be an invalid unit, so just give empty
if (aIndex < 0)
return "";
return PluralForm.get(aTime, gStr.timeUnits[aIndex]);
}
/**
* Private helper function to replace a placeholder string with a real string
*
* @param aText
* Source text containing placeholder (e.g., #1)
* @param aIndex
* Index number of placeholder to replace
* @param aValue
* New string to put in place of placeholder
* @return The string with placeholder replaced with the new string
*/
function replaceInsert(aText, aIndex, aValue)
{
return aText.replace("#" + aIndex, aValue);
}
/**
* Private helper function to log errors to the error console and command line
*
* @param aMsg
* Error message to log or an array of strings to concat
*/
function log(aMsg)
{
let msg = "DownloadUtils.jsm: " + (aMsg.join ? aMsg.join("") : aMsg);
Cc["@mozilla.org/consoleservice;1"].getService(Ci.nsIConsoleService).
logStringMessage(msg);
dump(msg + "\n");
}