function fxdownload(fileid,isselectPath,indexPath)
%FXDOWNLOAD  Download a file from MATLAB Central File Exchange.
%
%   FXDOWNLOAD(fileid) downloads a file with specified fileid into the
%   indexPath\fxdownloads directory. The indexPath is the downloads
%   location, retrieved from previous download. If downloading for the
%   first time it will prompt the user to select the download directory. If
%   the downloading file is a zip file, it will extracts the archived
%   contents of the file or else for all other formats just downloads the
%   file. These files are downloaded into a directory with name format
%   [filename][fileid] and after the download is complete it will CD to
%   this directory and opens up fxsummary.html page.
%
%   FXDOWNLOAD(fileid,isselectPath) downloads the file with specified
%   fileid with an option of selecting a indexPath, if isselectPath
%   is 1. If isselectPath is 0 indexPath is choosen from previous download.
%
%   FXDOWNLOAD(fileid,isselectPath,indexPath) downloads the file with
%   specified fileid with an option of passing indexPath. When passing an
%   indexPath isselectPath should be 0. If isselectPath is 1 it will
%   prompt the user to choose indexPath and overwrites the value that is
%   passed.
%
%   Example:
%     fxdownload(1613)
%     fxdownload(1613,1)
%     fxdownload(1613,0,'C:\matlab')
%
%   NOTE: 1.Fileid can be found in MATLAB Central->File Exchange site.
%         2.For every new indexPath, this function will
%         create a fxdownloads directory with in indexPath and then
%         download the file into respective file name. If for the
%         next download another directory, one level above or below the
%         fxdownloads, is choosen then it will not create fxdownloads
%         directory again. It will download the file into previous
%         fxdownloads directory.

%   Copyright 1984-2006 The MathWorks, Inc.
%   Author : Santosh Kasula

%default is set to 0 to get the value from getpref
if (nargin < 2), isselectPath = 0; end
if (nargin < 3), indexPath = ''; end

mainIndexPath = fullfile(fileparts(prefdir),'fxdownloads');
[indexPath,rootPath] = selectIndexPath(isselectPath,indexPath,mainIndexPath);
%exit if no indexPath is selected
if rootPath == 0
    return
end

intro = '<h1><center>File Exchange Downloads</center></h1>';
indexHtmlFilename = 'downloads_index.html';

searchstr = ['http://www.mathworks.com/matlabcentral/fileexchange/loadFile.do?objectId=' sprintf('%.0f',fileid)];
htmlText = urlread(searchstr);
filename = strrep(regexp(htmlText,'"fileName" value="(.*?)">','tokens','once'),' ','%20');

%File Extention
fe = regexp(htmlText,'name="fileExt" value="(.*?)">','tokens','once');
%contributorId
contributorId = regexp(htmlText,'"contributorId" value="(.*?)">','tokens','once');

%Download file URL
downloadFileURL = ['http://www.mathworks.com/matlabcentral/fileexchange/download.do?objectId=' sprintf('%.0f',fileid) ...
    '&fn=' filename{1} '&fe=' fe{1} '&cid=' contributorId{1}];

%Create a donwloaDir
[downloadDir,dirname,isOverWrite] = createdownloadDir(indexPath,fileid,filename);
if strcmp(isOverWrite,'Cancel')
    return
end

%download file
unzipfilenames = downloadfile(downloadFileURL,downloadDir,filename,fe);

%Get the relevant html info in a structure
d = relevantHtmlInfo(htmlText,fileid,filename,dirname,downloadDir,contributorId,unzipfilenames);

%Create an index page for all downloads in a particular location
writeIndex(indexPath,indexHtmlFilename,downloadDir,intro,d);

%Create a summary page for each individual download
createSummaryPage(indexPath,indexHtmlFilename,downloadDir)

%Create main index for all downloads in all locations
[dirPath fxdirname] = fileparts(fileparts(indexPath));
if strcmp(fxdirname,'fxdownloads')
    updatefxindex(fullfile(fileparts(indexPath),indexHtmlFilename),0);
end

%open fxsummary page
web(fullfile(downloadDir,'fxsummary.html'));

%==========================================================================
function [indexPath,rootPath] = selectIndexPath(isselectPath,indexPath,mainIndexPath)
%SELECTINDEXPATH  Select a direcoty to download a file.

%get the indexPath from the preference already set if indexPath is not
%passed
if ispref('fileexchange','prefindexPath') && isempty(indexPath)
    indexPath = getpref('fileexchange','prefindexPath');
end
rootPath = '';
%get the user input for indexPath if it is empty or user want to change the
%indexPath preference.
if isempty(indexPath) || isselectPath
    rootPath = uigetdir(cd,'Select a folder');
    %
    if rootPath == 0
        %exit if no directory is choosen
        return;
    end
    cd(rootPath);
    [dirpath filename ext] = fileparts(rootPath);
    %check the validity of the directory
    if isempty(ext)
        %check if the directory choosen is fxdownloads. if fxdownloads direcoty
        %is choosen assign user selected directory as indexPath or else
        %create a fxdownloads directory and assign it indexPath
        if ~isempty(filename)
            [localdirPath localFilename] = fileparts(dirpath);
            if ~strcmp(filename,'fxdownloads') && ~strcmp(localFilename,'fxdownloads')
                [subdirpath subfilename] = fileparts(dirpath);
                if strcmp(subfilename,'fxdownloads')
                    indexPath = rootPath;
                else
                    if ~isdir('fxdownloads')
                        [status, message, mesageid] = mkdir('fxdownloads');
                        if status == 0
                            errordlg([mesageid ': ' message],'Error');
                        end
                        indexPath = fullfile(rootPath,'fxdownloads');

                    else
                        indexPath = fullfile(rootPath,'fxdownloads');
                    end
                end
            else
                indexPath = rootPath;
            end
        else
            indexPath = fullfile(rootPath,'fxdownloads');
        end
        if ispref('fileexchange','prefindexPath')
            setpref('fileexchange','prefindexPath',indexPath);
        else
            addpref('fileexchange','prefindexPath',indexPath);
        end
    else
        errordlg('Invalid filname.', 'Error');
    end
end
%check if prefindexPath preferece is already existing if not add prefindexPath
%preference to fileexchange group
saveindexPath(indexPath,mainIndexPath);


%==========================================================================
function saveindexPath(indexPath,mainIndexPath)
%SAVEINDEXPATH  Save the selected indexPath into a mat file.

if ~isdir(mainIndexPath)
    mkdir(mainIndexPath)
end
filename = dir(fullfile(mainIndexPath,'indexPathList.mat'));
if ~isempty(filename)
    load(fullfile(mainIndexPath,'indexPathList.mat'),'newindexPathList');
    for i=1:length(newindexPathList)
        if strcmp(newindexPathList(i).indexPath,indexPath)
            isindexPathexisting = true;
            newindexPathList(i).indexPath = indexPath;
            break;
        else
            isindexPathexisting = false;
        end
    end
    if ~isindexPathexisting
        newindexPathList(length(newindexPathList)+1).indexPath = indexPath; %#ok<NASGU>
    end
else
    newindexPathList(1).indexPath = indexPath;
end
save (fullfile(mainIndexPath,'indexPathList.mat'),'newindexPathList');

%==========================================================================
function [downloadDir,dirname,isOverWrite] = createdownloadDir(indexPath,fileid,filename)
%CREATEDOWNLOADDIR  Create a directory name in the format [filename][fid].

dirname = strrep(strcat(strrep(filename{1},'.','_'),sprintf('%.0f',fileid)),'%20','_');
downloadDir = strrep(fullfile(indexPath,dirname),'%20',' ');
isdirExsting = isdir(downloadDir);

%by default do not overwrite a folder
isOverWrite = 'yes';

%If directroy already existing ask the user to Overwrite/Cancel?
if isdirExsting
    isOverWrite = questdlg('The Directory already exists. Do you want to Overwrite? ','Directory already existing','Ok','Cancel','Ok');
    %   ButtonName = questdlg('What is your favorite color?','Color Question','Red', 'Green', 'Blue', 'Green');
    if isempty(isOverWrite)
        isOverWrite = 'Cancel';
    end
    switch  lower(isOverWrite)
        case 'ok'
            cd ..
            rmdir(downloadDir,'s')
        case 'cancel'
            return
    end
end

%Create a Download directory
[status, message, mesageid] = mkdir(downloadDir);
%Return if there is any error in the directory creation
if status == 0
    error(mesageid, message);
end
%==========================================================================
function unzipfilenames = downloadfile(downloadFileURL,downloadDir,filename,fe)
%DOWNLOADFILE  Download a file.

%Download the file
if strcmp(fe{1},'.zip')
    %If zip file, unzip the file in download directory
    tempdownloadDir = fullfile(tempdir,'fxdownloads');
    mkdir(tempdownloadDir);
    [tempHtmlfile,status] = urlwrite(downloadFileURL,fullfile(tempdownloadDir,strcat(filename{1},'.html')));
    if isequal(status,1)
        unzip(tempHtmlfile, tempdownloadDir);
        delete(tempHtmlfile);
    else
        error('Error unzipping the URL')
    end
    dirlist = getsubdirs(tempdownloadDir);
    mfilecount=0;
    allfilecount = 0;
    for n=1:length(dirlist)
        allfiles = dir(dirlist{n});
        allfiles = allfiles(logical(~[allfiles.isdir]));
        if ~isempty(allfiles)
            for k=1:length(allfiles)
                allfilecount = allfilecount + 1;
                allunzipfiles{allfilecount} = fullfile(dirlist{n},allfiles(k).name);
            end
        end
    end
    dirfiles = tempdownloadDir;
    while true
        tempdirfiles = dir(dirfiles);
        if length(tempdirfiles) <= 3 && length(tempdirfiles(logical([tempdirfiles.isdir]))) >= 3
            for n = 1:length(tempdirfiles)
                if      ~strcmp(tempdirfiles(n).name(1),'.') && ...
                        ~strcmp(tempdirfiles(n).name,'.') && ...
                        ~strcmp(tempdirfiles(n).name,'..') && ...
                        tempdirfiles(n).isdir
                    tempdirfilename = tempdirfiles(n).name;
                end
            end
            dirfiles = fullfile(dirfiles,tempdirfilename);
        else
            break;
        end
    end
    [status,message,messageid] = copyfile(dirfiles,downloadDir,'f');
    for i=1:length(allunzipfiles)
        unzipfilenames(i) = strrep(strrep(allunzipfiles(i),dirfiles,downloadDir),'/','\');
    end
    %Return if there is any error in the directory moving
    if status == 0
        error(mesageid, message);
    end
    cd(tempdir);
    rmdir(tempdownloadDir,'s');
else
    %any file extension save the file in download directory