mirror of
https://github.com/kiwix/kiwix-js.git
synced 2025-09-22 03:52:21 -04:00
Random article feature : start reading titles after a newLine. Fixes #69
This commit is contained in:
mossroy
parent
cec89f82b0
commit
c5dd935f3d
File diff suppressed because it is too large
Load Diff
@ -1,126 +1,127 @@
|
||||
/**
|
||||
* titleIterators.js : Various classes to iterate over titles, for example as a
|
||||
* result of searching.
|
||||
*
|
||||
* Copyright 2014 Evopedia developers
|
||||
* License GPL v3:
|
||||
*
|
||||
* This file is part of Evopedia.
|
||||
*
|
||||
* Evopedia is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* Evopedia is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with Evopedia (file LICENSE-GPLv3.txt). If not, see <http://www.gnu.org/licenses/>
|
||||
*/
|
||||
define(['utf8', 'title', 'util', 'jquery'], function(utf8, evopediaTitle, util, jQuery) {
|
||||
// Maximum length of a title
|
||||
// 300 bytes is arbitrary : we actually do not really know how long the titles will be
|
||||
// But mediawiki titles seem to be limited to ~200 bytes, so 300 should be more than enough
|
||||
var MAX_TITLE_LENGTH = 300;
|
||||
|
||||
/**
|
||||
* Iterates over all titles starting at the given offset.
|
||||
* The asynchronous method advance has to be called before this.title is
|
||||
* valid.
|
||||
* @param archive
|
||||
* @param offset
|
||||
*/
|
||||
function SequentialTitleIterator(archive, offset) {
|
||||
this._titleFile = archive.titleFile;
|
||||
this._archive = archive;
|
||||
this._offset = offset;
|
||||
this.title = null;
|
||||
};
|
||||
/**
|
||||
* Advances to the next title (or the first), if possible.
|
||||
* @returns jQuery promise containing the next title or null if there is no
|
||||
* next title
|
||||
*/
|
||||
SequentialTitleIterator.prototype.advance = function() {
|
||||
if (this._offset >= this._titleFile.size) {
|
||||
this.title = null;
|
||||
return jQuery.when(this.title);
|
||||
}
|
||||
var that = this;
|
||||
return util.readFileSlice(this._titleFile, this._offset,
|
||||
this._offset + MAX_TITLE_LENGTH).then(function(byteArray) {
|
||||
var newLineIndex = 15;
|
||||
while (newLineIndex < byteArray.length && byteArray[newLineIndex] !== 10) {
|
||||
newLineIndex++;
|
||||
}
|
||||
var encodedTitle = byteArray.subarray(0, newLineIndex);
|
||||
that._title = evopediaTitle.Title.parseTitle(encodedTitle, that._archive, that._offset);
|
||||
that._offset += newLineIndex + 1;
|
||||
return that._title;
|
||||
});
|
||||
};
|
||||
|
||||
/**
|
||||
* Searches for the offset into the given title file where the first title
|
||||
* with the given prefix (or lexicographically larger) is located.
|
||||
* The given function normalize is applied to every title before comparison.
|
||||
* @param titleFile
|
||||
* @param prefix
|
||||
* @param normalize function to be applied to every title before comparison
|
||||
* @returns jQuery promise giving the offset
|
||||
*/
|
||||
function findPrefixOffset(titleFile, prefix, normalize) {
|
||||
prefix = normalize(prefix);
|
||||
var lo = 0;
|
||||
var hi = titleFile.size;
|
||||
var iterate = function() {
|
||||
if (lo >= hi - 1) {
|
||||
if (lo > 0)
|
||||
lo += 2; // Let lo point to the start of an entry
|
||||
return jQuery.when(lo);
|
||||
} else {
|
||||
var mid = Math.floor((lo + hi) / 2);
|
||||
return util.readFileSlice(titleFile, mid, mid + MAX_TITLE_LENGTH).then(function(byteArray) {
|
||||
// Look for the index of the next NewLine
|
||||
var newLineIndex = 0;
|
||||
while (newLineIndex < byteArray.length && byteArray[newLineIndex] !== 10) {
|
||||
newLineIndex++;
|
||||
}
|
||||
var startIndex = 0;
|
||||
if (mid > 0) {
|
||||
startIndex = newLineIndex + 16;
|
||||
newLineIndex = startIndex;
|
||||
// Look for the index of the next NewLine
|
||||
while (newLineIndex < byteArray.length && byteArray[newLineIndex] !== 10) {
|
||||
newLineIndex++;
|
||||
}
|
||||
}
|
||||
if (newLineIndex === startIndex) {
|
||||
// End of file reached
|
||||
hi = mid;
|
||||
} else {
|
||||
var normalizedTitle = normalize(utf8.parse(byteArray.subarray(startIndex, newLineIndex)));
|
||||
if (normalizedTitle < prefix) {
|
||||
lo = mid + newLineIndex - 1;
|
||||
} else {
|
||||
hi = mid;
|
||||
}
|
||||
}
|
||||
return iterate();
|
||||
});
|
||||
}
|
||||
};
|
||||
return iterate();
|
||||
}
|
||||
|
||||
/**
|
||||
* Functions and classes exposed by this module
|
||||
*/
|
||||
return {
|
||||
SequentialTitleIterator : SequentialTitleIterator,
|
||||
findPrefixOffset : findPrefixOffset
|
||||
};
|
||||
});
|
||||
/**
|
||||
* titleIterators.js : Various classes to iterate over titles, for example as a
|
||||
* result of searching.
|
||||
*
|
||||
* Copyright 2014 Evopedia developers
|
||||
* License GPL v3:
|
||||
*
|
||||
* This file is part of Evopedia.
|
||||
*
|
||||
* Evopedia is free software: you can redistribute it and/or modify
|
||||
* it under the terms of the GNU General Public License as published by
|
||||
* the Free Software Foundation, either version 3 of the License, or
|
||||
* (at your option) any later version.
|
||||
*
|
||||
* Evopedia is distributed in the hope that it will be useful,
|
||||
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||||
* GNU General Public License for more details.
|
||||
*
|
||||
* You should have received a copy of the GNU General Public License
|
||||
* along with Evopedia (file LICENSE-GPLv3.txt). If not, see <http://www.gnu.org/licenses/>
|
||||
*/
|
||||
define(['utf8', 'title', 'util', 'jquery'], function(utf8, evopediaTitle, util, jQuery) {
|
||||
// Maximum length of a title
|
||||
// 300 bytes is arbitrary : we actually do not really know how long the titles will be
|
||||
// But mediawiki titles seem to be limited to ~200 bytes, so 300 should be more than enough
|
||||
var MAX_TITLE_LENGTH = 300;
|
||||
|
||||
/**
|
||||
* Iterates over all titles starting at the given offset.
|
||||
* The asynchronous method advance has to be called before this.title is
|
||||
* valid.
|
||||
* @param archive
|
||||
* @param offset
|
||||
*/
|
||||
function SequentialTitleIterator(archive, offset) {
|
||||
this._titleFile = archive.titleFile;
|
||||
this._archive = archive;
|
||||
this._offset = offset;
|
||||
this.title = null;
|
||||
};
|
||||
/**
|
||||
* Advances to the next title (or the first), if possible.
|
||||
* @returns jQuery promise containing the next title or null if there is no
|
||||
* next title
|
||||
*/
|
||||
SequentialTitleIterator.prototype.advance = function() {
|
||||
if (this._offset >= this._titleFile.size) {
|
||||
this.title = null;
|
||||
return jQuery.when(this.title);
|
||||
}
|
||||
var that = this;
|
||||
return util.readFileSlice(this._titleFile, this._offset,
|
||||
this._offset + MAX_TITLE_LENGTH).then(function(byteArray) {
|
||||
var newLineIndex = 15;
|
||||
while (newLineIndex < byteArray.length && byteArray[newLineIndex] !== 10) {
|
||||
newLineIndex++;
|
||||
}
|
||||
var encodedTitle = byteArray.subarray(0, newLineIndex);
|
||||
that._title = evopediaTitle.Title.parseTitle(encodedTitle, that._archive, that._offset);
|
||||
that._offset += newLineIndex + 1;
|
||||
return that._title;
|
||||
});
|
||||
};
|
||||
|
||||
/**
|
||||
* Searches for the offset into the given title file where the first title
|
||||
* with the given prefix (or lexicographically larger) is located.
|
||||
* The given function normalize is applied to every title before comparison.
|
||||
* @param titleFile
|
||||
* @param prefix
|
||||
* @param normalize function to be applied to every title before comparison
|
||||
* @returns jQuery promise giving the offset
|
||||
*/
|
||||
function findPrefixOffset(titleFile, prefix, normalize) {
|
||||
prefix = normalize(prefix);
|
||||
var lo = 0;
|
||||
var hi = titleFile.size;
|
||||
var iterate = function() {
|
||||
if (lo >= hi - 1) {
|
||||
if (lo > 0)
|
||||
lo += 2; // Let lo point to the start of an entry
|
||||
return jQuery.when(lo);
|
||||
} else {
|
||||
var mid = Math.floor((lo + hi) / 2);
|
||||
return util.readFileSlice(titleFile, mid, mid + MAX_TITLE_LENGTH).then(function(byteArray) {
|
||||
// Look for the index of the next NewLine
|
||||
var newLineIndex = 0;
|
||||
while (newLineIndex < byteArray.length && byteArray[newLineIndex] !== 10) {
|
||||
newLineIndex++;
|
||||
}
|
||||
var startIndex = 0;
|
||||
if (mid > 0) {
|
||||
startIndex = newLineIndex + 16;
|
||||
newLineIndex = startIndex;
|
||||
// Look for the index of the next NewLine
|
||||
while (newLineIndex < byteArray.length && byteArray[newLineIndex] !== 10) {
|
||||
newLineIndex++;
|
||||
}
|
||||
}
|
||||
if (newLineIndex === startIndex) {
|
||||
// End of file reached
|
||||
hi = mid;
|
||||
} else {
|
||||
var normalizedTitle = normalize(utf8.parse(byteArray.subarray(startIndex, newLineIndex)));
|
||||
if (normalizedTitle < prefix) {
|
||||
lo = mid + newLineIndex - 1;
|
||||
} else {
|
||||
hi = mid;
|
||||
}
|
||||
}
|
||||
return iterate();
|
||||
});
|
||||
}
|
||||
};
|
||||
return iterate();
|
||||
}
|
||||
|
||||
/**
|
||||
* Functions and classes exposed by this module
|
||||
*/
|
||||
return {
|
||||
SequentialTitleIterator : SequentialTitleIterator,
|
||||
findPrefixOffset : findPrefixOffset,
|
||||
MAX_TITLE_LENGTH : MAX_TITLE_LENGTH
|
||||
};
|
||||
});
|
||||
|
||||
Loading…
x
Reference in New Issue
Block a user