Coding Friends

CS107 – Assignment 2 – Six degrees

genux — Wed, 25 Aug 2010 19:54:32 +0000

This is assignment 2 from a older CS107 course, because the latest course work is held on a UNIX server which in turn you need access to!!.. kinder does not help when you do not have access too!!.. Here is where I got the files from cs107 link, there is a zip file at the bottom of that page which has all of the assignments and handouts etc.

I have included the PDF of the assignment in the above file link, but since the actual assignment includes a few massive files you can download them from the CS107 link of the whole course work that I am using from the cs107 link.

As a note, within my linux setup, I need to setup the environment variable to tell the program to use a Linux little endian by

export OSTYPE=linux

Basically the assignment is to load in cast/movie details (which the base code from the assignment already does for use) and then we are needed to pull out the data from the structure of the file, the structure of the actors is (as taken from the PDF file)

The name of the actor is laid out character by character, as a normal null-terminated C-string. If the length of the actor’s name is even, then the string is
padded with an extra ‘\0′ so that the total number of bytes dedicated to the name is always an even number. The information that follows the name is most
easily interpreted as a short integer, and virtually all hardware constrains any address manipulated as a short * to be even.
The number of movies in which the actor has appeared, expressed as a two-byte short. (Some people have been in more than 255 movies, so a single byte just
isn’t enough.) If the number of bytes dedicated to the actor’s name (always even) and the short (always 2) isn’t a multiple of four, then two additional ‘\0′’s
appear after the two bytes storing the number of movies. This padding is conditionally done so that the 4-byte integers than follow sit at addresses that are
multiples of four.
An array of offsets into the movieFile image, where each offset identifies one of the actor’s films.

with the base of the actors information containing a 4 byte integer value of how many actors are in the block of data and then the following values are in 4 bytes again with the offsets into the block of where the actual data is stored.

So the method that you need to write is to pull in that data from the actorInfo block of memory, and here is my version of it, the method is getCredits and takes the cast member (player) as the method will insert all of the films that cast as been in.

bool imdb::getCredits(const string& player, vector<film>& films) const
{
    int numberOfActors,data;
    char *actorName;
    memcpy(&numberOfActors,(int*)actorInfo.fileMap, 4);
    // loop though the number of actors
    for (int i =2; i < numberOfActors; i++)
    {
        memcpy(&data, ((int*)actorInfo.fileMap)+i,4);
        actorName = ((char*)actorInfo.fileMap + (data));
        if (strcmp(actorName,player.c_str())==0)
        {
            // find the padding lengths
            int actorNameLength = strlen(actorName)+1;
            int movieNumberPad = actorNameLength % 2;
            int fourOffset = (actorNameLength + movieNumberPad + 2) % 4;
            short numberMovies;
            memcpy(&numberMovies,((short*)((char*)actorInfo.fileMap + data + actorNameLength + movieNumberPad)),2);
            for (int j=0; j < numberMovies; j++)
            {
                int movieOffset;
                film theFilm;
                memcpy(&movieOffset, ((int*)((char*)actorInfo.fileMap + data + actorNameLength + movieNumberPad + (j*4) + fourOffset + 2)),4);
                theFilm.title = ((char*)movieInfo.fileMap + movieOffset);
                theFilm.year = 1900 + (int)((char*)movieInfo.fileMap + movieOffset + theFilm.title.length() + 1)[0];
                films.push_back(theFilm);
            }
            return true;
        }
    }
    return false;
}

The block of memory for the movie block is similar to the actor block and as taken from the PDF attached file here is the details of that block of memory,

The title of the movie, terminated by a ‘\0′ so the character array behaves as a normal C-string.
The year the film was released, expressed as a single byte. This byte stores the year – 1900. Since Hollywood is less than 28 years old, it was fine to just store the year as a delta from 1900. If the total number of bytes used to encode the name and year of the movie is odd, then an extra ‘\0′ sits in between the one-byte year and the data that follows.
A two-byte short storing the number of actors appearing in the film, padded with two additional bytes of zeroes if needed.
An array of four-byte integer offsets, where each integer offset identifies one of the actors in the actorFile. The number of offsets here is, of course, equal to
the short integer read during step 3

And once again like the actor block there is a 4 byte integer value that stores how many movies within the block of memory with the next 4 bytes storing the offset into that block of memory, here is my implementation of the method getCast that will take a movie as a parameter and find all of the cast (players) and return that vector list.

bool imdb::getCast(const film& movie, vector<string>& players) const
{
    int numberOfMovies, data;
    film theFilm;
    char *movieName;
    memcpy(&numberOfMovies, (int*)movieInfo.fileMap, 4);
    for (int i = 1; i < numberOfMovies; i++)
    {
        memcpy(&data, (int*)movieInfo.fileMap+i,4);
        movieName = ((char*)movieInfo.fileMap + data);
        theFilm.title = movieName;
        theFilm.year = 1900 + (int)((char*)movieInfo.fileMap + data + theFilm.title.length() + 1)[0];
        if (movie == theFilm)
        {
            int paddingFirst = theFilm.title.length() % 2;
            // paddingSecond = paddingfirst + length of title + 2 (year + \0) and then + 2 for the actors number
            int paddingSecond = (paddingFirst + theFilm.title.length() +2 + 2) %4;
            short numberOfActors;
            memcpy(&numberOfActors, (short*)((char*)movieInfo.fileMap + data + theFilm.title.length() + 2 + paddingFirst),2);
 
            // get the actors offsets and insert into the players list
            for (int k =0; k < numberOfActors; k++)
            {
                int offset;
                memcpy(&offset, ((int*)((char*)movieInfo.fileMap + data + strlen(movieName) + 2 + paddingFirst + 2 + paddingSecond + (k*4))), 4);
                players.push_back((char*)actorInfo.fileMap + offset);
            }
            return true;
        }
    }
    return false;
}

After you have sorted out reading in the information you have to find out if there is a link from actor1 to another actor2 (six degrees) with linking them together the cast that they have been with with the films that they have stared in, so here is my breath search setup as taken from the assignment.

/**
  * @param actor1 - first actor to look for
  * @param actor2 - second actor to look for to link to the first
  * @param db - the imdb database loaded
  */
static bool generateShortestPath(const string& actor1, const string& actor2, const imdb& db)
{
    list<path> partialPaths;
    set<string> previouslySeenActors;
    set<film> previouslySeenFilms;
 
    path actorsFirst(actor1);
    partialPaths.push_front(actorsFirst);
 
    while (!partialPaths.empty() && partialPaths.front().getLength() <=5)
    {
        path frontPath = (path)partialPaths.front();
        partialPaths.pop_front();
        vector<film> actorsFilms;
        db.getCredits(frontPath.getLastPlayer(), actorsFilms);
        for (int filmI=0; filmI < actorsFilms.size(); filmI++)
        {
            film filmData;
            filmData = actorsFilms.at(filmI);
            // not seen the film before
            if (previouslySeenFilms.find(filmData) == previouslySeenFilms.end())
            {
                previouslySeenFilms.insert(filmData);
                vector<string> movieCast;
                db.getCast(filmData, movieCast);
                for (int castI =0; castI < movieCast.size(); castI++)
                {
                    // if not already seen
                    if (previouslySeenActors.find(movieCast.at(castI)) == previouslySeenActors.end())
                    {
                        previouslySeenActors.insert(movieCast.at(castI));
                        path newfrontPath = frontPath;
                        newfrontPath.addConnection(filmData, movieCast.at(castI));
                        if (movieCast.at(castI) == actor2)
                        {
                            cout << newfrontPath << endl;
                            return true;
                        } else
                            partialPaths.push_back(newfrontPath);
                    }
                }
            }
        }
    }
    return false;
}

You can do some speed ups from the assignments PDF file, but they are mainly the icing on the cake and I thought that I would assignment 3 first, so if I do the extras for this I will update this post.

But this was a fun assignment, because of the memory block and finding out the data within it.

threads – singleton

genux — Tue, 17 Aug 2010 08:31:57 +0000

As from one of my previous posts about threading in csharp (c#), well with using Singletons you can use similar data between two different threads running.

In basics a singleton is when you want to have a single class instance so that you can share this class so that every time that you use it (even across threads) will only access the same class, it is very useful for when you have a printer spool so that you do not want to have x amount of printer spools (spool is when you have a list of print tasks waiting to print) and thus you only want to have one instance of a printer spool !!.

I have used the singleton creation from Microsoft website, that creates a singleton class that is thread safe which means that I am using the lock method that will lock on a object to stop thread contention and thus only creates a new instance of a Singleton class so that each thread will only get access to a single instance of that class.

So when you want to gain access to that single instance, you just call the

Singleton theSingleton = Singleton.Instance;

So here is the full source code, and below is the output where the output is displaying the value is incrementing otherwise if is was not a singleton class, the main class would print out 0-4 and also the runthismethod would output 0-9 instead!.

using System;
using System.Threading;
 
namespace monotestproject
{
	public sealed class Singleton
	{
		private static int _value;
		private static volatile Singleton instance;
		private static object syncRoot = new Object();
 
		public Singleton() { _value = 0;}
 
		public static Singleton Instance
		{
			get { 
				if (instance == null)
				{
					lock(syncRoot)
					{
						if (instance == null)
							instance = new Singleton();
					}
				}
				return instance;
			}
			private set {}
		}
 
		public int theValue 
		{
			get { return _value;}
			set { _value = value;}
		}
	}
 
	class MainClass
	{
		public static void Main (string[] args)
		{
			Singleton theSingleton = Singleton.Instance;
			// initialize the RunThisMethod as a thread
			Thread theThread = new Thread(RunThisMethod);
			theThread.Start();
 
			for (int j = 0; j < 5; j++)
			{
				theSingleton.theValue++;
				Console.WriteLine("Main Singleton value " + theSingleton.theValue);
				Thread.Sleep(100);
			}
		}
 
		// the method to create as a threadable method
		public static void RunThisMethod()
		{
			Singleton runsSingleton = Singleton.Instance;		
			for (int i =0; i < 10; i++)
			{
				runsSingleton.theValue++;
				Console.WriteLine("RunThisMethod Singleton value " + runsSingleton.theValue);
				Thread.Sleep(45);
			}
		}
	}
}

here is my output, as you can I am getting the singleton value incrementing, which is what should be happening.

Main Singleton value 1
RunThisMethod Singleton value 2
RunThisMethod Singleton value 3
RunThisMethod Singleton value 4
Main Singleton value 5
RunThisMethod Singleton value 6
RunThisMethod Singleton value 7
Main Singleton value 8
RunThisMethod Singleton value 9
RunThisMethod Singleton value 10
Main Singleton value 11
RunThisMethod Singleton value 12
RunThisMethod Singleton value 13
Main Singleton value 14
RunThisMethod Singleton value 15

unsafe – pointers in the code

genux — Fri, 13 Aug 2010 10:16:15 +0000

Sometimes you do miss that pointer part of c++ coding within c#, well you can get around the restriction with using the unsafe syntax which basically means that you are doing some coding that please do not use the restrictions of the virtual machine and just allow direct access to the variable/memory as such.

So the basics is the

// for a block code
unsafe {
code here..
}
// or for the whole method.
public unsafe <returntype> <methodname>
{
}

So to show the code in real code, this will setup a int(eger) value to 50 and then point to the data via a pointer (*) and then you can see that the actual value within the pointer (*) is not the same and also will change every time since the int(eger) value of 50 memory location will most probably be different every time.

using System;
 
namespace unsafetest
{
    class Program
    {
        static void Main(string[] args)
        {
            unsafe
            {
                int intValue = 50;
                Console.WriteLine("integer value is : " + intValue);
                int* pointerInt = &intValue;
                Console.WriteLine("Pointer to the data is : " + *pointerInt);
                Console.WriteLine("Pointed to the memory value of data is : " + (int)pointerInt);
            }
            Console.ReadLine();
        }
    }
}

the output would be similar to, I am using a (int) cast on the memory location, which since the memory location is very big then it would be better to use something like a hex value output, but this just shows that the value will be different on different runs, if you run it again and again, that will be different values.

integer value is : 50
Pointer to the data is : 50
Pointed to the memory value of data is : 98691076

MySQL storage engines

genux — Thu, 12 Aug 2010 13:00:38 +0000

In MySQL, there is a couple of different storage engines that can be used for different tables within a database. There is myiasm, innodb, cvs, memory, merge, BDB (BerkeleyDB) example, federated, archive and blackhole.

The main two are that are used are

The main differences between them both are speed, the myiasm is more designed for speed to access the database tables but does not support the rollback where you are able stop the current set of instructions and rollback the updates/inserts to where it was at a previous time, because of this the programmer is the person to make sure that what they want to do is and will happen, otherwise the programmer will have to sort out the tables that could out of stink. But compared to the innodb, where it supports the rollback function, it does have to take a hit somewhere and that is the speed.

The main database that I use is the myiasm, purely because of the speed of access, and also it appears that most web/applications appear to use that. But if you running some circuital data then of course I would use innodb database type purely for data.

CS71 – Ass1 – Finance – Part 5 – View users details – buy stock – change password

genux — Wed, 11 Aug 2010 15:51:30 +0000

I am doing the Harvards building dynamic websites called CS-75 (also could be called E-75), because someone told me about it and I just thought might as well, it is all learning even if allot of it you may already know.

As from the previous post, most of this page is in similar in nature it is just displaying data to the user that was built up from the classes files.

So to buy some stock, what this page will do is wait for the user to type in a stock symbol and then use the stock class to get the data back from that symbol and then have another input that will allow the user to buy some of that stock, also if the user clicks on the link it will display at the bottom of the page new items about the stock itself.

 

	require("functions_start.php");
 
	global $theStock;
 
	if (!isset($_SESSION["authenticated"]) || $_SESSION["authenticated"]== false)
	{
		header("Location: /index.php");
		exit;
	}
 
	// of course the product price may change from searching to buying, depending on the time period so need to pull back 
	// the new value, just incase.
	if (isset($_REQUEST["buyme"]))
	{
		$stockID = strtoupper($_REQUEST["STOCK"]);
		$stockAmount = $_REQUEST["AMOUNT"];
		$stockPurchased = $theStock->BuyStock($_SESSION["username"], $stockID, $stockAmount);
	}
 
	if (isset($_REQUEST["searchSymbol"]))
	{
		if (strlen($_REQUEST["searchSymbol"]) >=3)
			$result = $theStock->GetStocksFromYahoo(strtoupper($_REQUEST["searchSymbol"]));
	}
 
	HTMLHeader("Buy some stock, search and buy");
 
	if (isset ($stockPurchased)) {
		echo "\"details\">";
		if ($stockPurchased >0 )
			echo "Stock was purchased ($stockID amount of $StockAmount total price of $stockPurchased each price was ". number_format($stockPurchased / $stockAmount,2).")"; 
		else
			echo "Problem with purchasing the stock, please email the error above to the support team";
		echo "
";
	}
?>
 echo $_SERVER["PHP_SELF"]; ?>" method="post" onsubmit="return CheckBuy()"/>

if (isset($result)) { 
  if ($result > 0) {
	echo "{$_REQUEST["searchSymbol"]}
";
    echo "The price of {$_REQUEST["searchSymbol"]} is $result, do you want to buy ?
Please enter how many and tick the box.
";
	echo "\"text\" name=\"AMOUNT\" id=\"AMOUNT\" onkeyup=\"javascript:CheckKey(this)\"/>";
	echo "\"hidden\" name=\"STOCK\" value=\"{$_REQUEST["searchSymbol"]}\"/>";
	echo "\"checkbox\" name=\"buyme\" id=\"BUYME\"/>";
	echo "\"submit\" value=\"Submit\"/>";
	echo "Or search for another stock
";
 }
else
    echo "Not stock of that symbol - {$_REQUEST["searchSymbol"]}
";
}
?>


Search Symbol :


Your present cash flow is

	echo number_format($theUser->GetCash($_SESSION["username"]),2);
 
	HTMLFooter();
?>

To view the stock details of the user, I just display the stock that the user has from data once again from the stock class, which also includes the current price of the stock. There is a checkbox that will allow the user to sell some of there stock (if they have any!!) and once again use the stock class to sell the stock and update the tables in the database.


	require("functions_start.php");
 
	global $theStock;
 
	if (!isset($_SESSION["authenticated"]) || $_SESSION["authenticated"]== false)
	{
		header("Location: /index.php");
		exit;
	}
	foreach ($_REQUEST as $key => $value)
	{
		if (strpos($key, "remove_") === 0)
			$theStock->SellStock($_SESSION["username"], $value);
		if ($key=="stock")
			$getStock = $value;
	}
	HTMLHeader("The details of your account");
?>
The stocks that the user has
 echo $_SERVER["PHP_SELF"];?>" method="post" onsubmit="return checkSell()">

    $totalValue = 0;
	$usersStock = $theStock->ReturnAllStocks($_SESSION["username"]);
	foreach ($usersStock as $theStocks)
	{
		echo "";$totalValue+=$theStocks[2]*$theStocks[1];}echo"";?>
Stock Name Quantity Price of Stock Value Sell
\"{$_SERVER["PHP_SELF"]}?stock={$theStocks[0]}\">{$theStocks[0]} {$theStocks[1]} {$theStocks[2]} ".
			number_format($theStocks[2] * $theStocks[1],2)." \"checkbox\" value=\"{$theStocks[0]}\" name=\"remove_{$theStocks[0]}\"/>
		    
	
	 \"2\"> Total value ".number_format($totalValue,2)."




Your present cash flow is

	echo number_format($theUser->GetCash($_SESSION["username"]),2);
	echo "Your cash + investments
" . number_format($theUser->GetCash($_SESSION["username"]) + $totalValue,2);
 
	if (isset($getStock))
	{
		echo "$getStock more information
";$stockDetailsArray=$theStock->ArrayOfStockDetails($getStock);for($i=0;$i<sizeof($stockDetailsArray);$i++){echo"Date Title/Link
		  
		       
		
			 {$stockDetailsArray[$i]["Date"]} \"{$stockDetailsArray[$i]["Link"]}\" target=\"_blank\">{$stockDetailsArray[$i]["Title"]}";
		}
		echo "
";
	}
 
	HTMLFooter();
?>

The last part is the change of the password, which just will use the user class to update the users password to the requested input from the change password page.


	require("functions_start.php");
 
	if (isset($_REQUEST["password1"]) && isset($_REQUEST["password2"]))
	{
		if ($_REQUEST["password1"] == $_REQUEST["password2"])
			$error = $theUser->ChangePassword($_SESSION["username"], $_REQUEST["password1"]);
		else
			$notSamePassword = true;
	}
 
	if (!isset($_SESSION["authenticated"]))
	{
		header("Location: /index.php");
		exit;
	}
 
	HTMLHeader("Change password",true);
 
	if (isset($error))
	{
		if ($error)
			echo "Password updated
";
		else 
			echo "\"error\">Cannot update the password, please contact the system admin
";
	}
	if (isset($notSamePassword))
		echo "Passwords are not the same
";
?>



     

 echo $_SERVER["PHP_SELF"]; ?>" onsubmit="return CheckChangePasswords()">
Change your password 
New Password : 
Retype New Password : 




     



	HTMLFooter();
?>

The actual pages that are displayed to the user are all very basic as them selves, but the actual logic and formula are all within the classes that is the gold dust as such, since it is one point of checking and also one file to update if there is a update to the yahoo etc stocks details, because would have to update the different pages that display the stocks and that is not good for testing and also updating.

CS71 – Ass1 – Finance – Part 4 – Login Register Forgotten password

genux — Wed, 11 Aug 2010 15:41:39 +0000

Since most of the work is done in the class files, from the previous post then we just use the classes to only have basic php pages for the user. So the login page is just, which also has a check for if the user is already logged in and goto the viewdetails page, or if the user requests to logout then logout the user, the main page is just logging the user in.


	require("functions_start.php");
 
	if (isset($_REQUEST["username"]) && isset($_REQUEST["password"]))
	{
		$error = $theUser->LoginCheck($_REQUEST["username"], $_REQUEST["password"]);
	}
 
	if (isset($_REQUEST["logout"]))
		$theUser->Logout();
 
	if (isset($_SESSION["authenticated"]) && $_SESSION["authenticated"]== true)
	{
		header("Location: /viewdetails.php");
		exit;
	}
 
	HTMLHeader("Login to the stocks!",false);
 
	if (isset($error))
	{
		if ($error==false)
			echo "Not able to login, please try again
";
	}
	if (isset($_REQUEST["logout"])) 
		echo "Thanks for using the site, you are logged out!";
?>



     

 echo $_SERVER["PHP_SELF"]; ?>" onsubmit="">
Login

Username :  echo $_REQUEST["username"]; ?>"/>


Password : 





Register here.



     



	HTMLFooter();
?>

Here is the register page, where I send the request to the users class and utilize the return value to display either a message of check your emails (or in this case it will be a link on the top of the page) or display a error to the user depending on what could happen, e.g. not a valid valid/password(if the user turned off javascript checking) and also if there is already that email address present, the next check checks for the valid ID value that is sent to the user to validate there email.


	require("functions_start.php");
 
	if (isset($_REQUEST["username"]) && isset($_REQUEST["password"]))
	{
		$error = $theUser->RegisterUser($_REQUEST["username"], $_REQUEST["password"]);
		if ($error == -2)
			$notValidPassword = true;
		else if ($error == -1)
			$notValidEmail = true;
		else if ($error == 0)
			$emailAddressAlreadyPresent = true;
		else if ($error == 1)
			$checkEmails = true;
	}
 
	if (isset($_REQUEST["validid"]) && isset($_REQUEST["uid"]))
	{
		$error = $theUser->CheckUserGUID($_REQUEST["uid"], $_REQUEST["validid"]);
		if ($error == false)
			$userInvalid = true;
		else if ($error == true)
		{			
			$theUser->LoginCheck($_REQUEST["uid"],"",true);
			header("Location: /viewdetails.php");
			exit;
		}
	}
 
	if (isset($_SESSION["authenticated"]) && $_SESSION["authenticated"]== true)
	{
		header("Location: /viewdetails.php");
		exit;
	}
 
	HTMLHeader("Register",false);
 
	if (isset($error))
	{
		if (isset($checkEmails))
			echo "Please check your emails to validate your email address
";
		else if (isset($notValidPassword))
			echo "\"error\">Not a valid password!, please enter one that is 6 characters and has at least 1 aphla/numeric
";
		else if (isset($emailAddressAlreadyPresent))
			echo "\"error\">Please use the forgotten password recovery,  already email address registered
";
		else if (isset($notValidEmail))
			echo "\"error\">Not a valid email address
";
		else if (isset($userInvalid))
			echo "\"error\">Does not validate correctly, please contact the system admin
";
	}
?>



     

 echo $_SERVER["PHP_SELF"]; ?>" onsubmit="return CheckRegister()">
Register 
Username :  echo $_REQUEST["username"]; ?>"/>
(valid email address)

Password : 
(Has to be at least 6 characters and with 1 numeric and aplha character





     



	HTMLFooter();
?>

Here is the last part, that will allow the user to enter there email to be able to get a link to enable them to change there password.


	require("functions_start.php");
 
	if (isset($_REQUEST["username"]) )
	{
		$error = $theUser->ForgottenUser($_REQUEST["username"]);
		if ($error)
			$checkEmails = true;
		else 
			$notValidEmail = true;
	}
 
	if (isset($_REQUEST["validid"]) && isset($_REQUEST["uid"]))
	{
		$error = $theUser->CheckUserGUID($_REQUEST["uid"], $_REQUEST["validid"]);
		if ($error == false)
			$userInvalid = true;
		else if ($error == true)
		{			
			$theUser->LoginCheck($_REQUEST["uid"],"",true);
			header("Location: /changepassword.php");
			exit;
		}
	}
 
	if (isset($_SESSION["authenticated"]) && $_SESSION["authenticated"]== true)
	{
		header("Location: /viewdetails.php");
		exit;
	}
 
	HTMLHeader("Forgotten password",false);
 
	if (isset($error))
	{
		if (isset($checkEmails))
			echo "Please check your emails to validate your email address
";
		else if (isset($notValidEmail))
			echo "\"error\">Cannot find that email address
";
	}
?>



     

 echo $_SERVER["PHP_SELF"]; ?>" onsubmit="return CheckRegister(true)">
Forgotten password, please enter your username 
Username :  echo $_REQUEST["username"]; ?>"/>
(valid email address)




     



	HTMLFooter();
?>

As you can see the actual pages are really simple because most of the work is done in the class files

CS71 – Ass1 – Finance – Part 3 – javascript and common php page

genux — Wed, 11 Aug 2010 15:31:50 +0000

Before any of the actual pages start, they will all call this php file so that it will build up the classes and connect to the database, so to start with need to pull in there classes and also start the session. The two functions are the HTML header and footer parts of each page, so that do not have to alter every page to just add in another style as such, the last part is when we are creating the objects for the database/users/stocks.


	require("database.php");
	require("getstocks.php");
	require("user.php");
 
	session_start();
 
	function HTMLHeader($titleTag,$loggedIn = true)
	{
?>
 

  
    <span style="color: #000000; font-weight: bold;"><?php</span> <span style="color: #b1b100;">echo</span> <span style="color: #000088;">$titleTag</span><span style="color: #339933;">;</span><span style="color: #000000; font-weight: bold;">?></span>
	
	
  
 
 
	
	 if ($loggedIn) { ?>
	View your stock
	Buy stock
	Logout
	Change password
	 } else { ?>
	Login
	Register
	Forgotten password
	 } ?>
	


	}
 
	function HTMLFooter()
	{
?>





	}
 
	$db= new mysqlConnect("localhost", "username","password", "cs75_project1");
	$theStock = new StocksDetails();
	$theUser = new User();
?>

Because in the HTMLHeader function I am linking to the ass1.js file, which is the javascript code that will allow for a better user experience because we can do some input tests before sending to the server.

This is the function that checks the users input when they are trying to sell some of the stock that they have

function checkSell()
{
	var formElem = document.forms[0];
	var elemsEmpty =0;
	for (var i = 0; i < formElem.length; i++)
	{
		var elem = formElem[i];
		if (elem.type == "checkbox" && elem.checked)
			elemsEmpty++;
	}
	if (elemsEmpty ==0)
	{
		alert("Please select a item to sell");
		return false;
	}
	return true;
}

When the user is on the buying stock page, it would be good to make sure that the value is a integer value before the user actually sends the request to the server, it will also check to make sure that there is a symbol to search for, saves on just clicking on the submit without any data.

function CheckBuy()
{
	var symbol = document.getElementById("searchSymbol");
	var amount = document.getElementById("AMOUNT");
 
	if (symbol.value.length < 3 && amount == null)
	{
		alert("Please insert a search symbol");
		symbol.focus();
		return false;
	}
 
	if (amount != null && amount.length >0)
	{
		if (isNaN(amount) && amount.value > 0)
		{
			if (!document.getElementById("BUYME").checked)
			{
				alert("Please select the tick box next to the amount");
				return false;
			}	
		}
		else 
		{
			alert("Please enter a valid amount to buy");
			document.getElementById("AMOUNT").focus();
			return false;
		}
	}
	return true;
}

This function actually checks the users input on the amount of stock to buy and making sure that it is only numeric values.

// only allow integer values within the box
function CheckKey(boxToCheck)
{
	var boxValue="";
	for (i = 0; i < boxToCheck.value.length; i++)
	{
		if (!isNaN(boxToCheck.value[i]))
			boxValue += boxToCheck.value[i];
	}
	boxToCheck.value = boxValue;
}

This function, checks to make sure that the registration screen has a valid email address (does another check on the server if the user turns off javascript), and also checks the password for the correct format.

function CheckRegister(justUsername)
{
	var username = document.getElementById("username");
	var password = document.getElementById("password");
	if (username.value.match(/^([a-zA-Z0-9_.-])+@([a-zA-Z0-9_.-])+\.([a-zA-Z])+([a-zA-Z])+/)) {
		if (justUsername)
			return true;
		return CheckPassword(password);
    }else{   
		alert("Incorrect email format"); 
    }
	return false;
}

This the actual function that will check the password is in the correct format, e.g. 1+ numeric/alpha characters. and more than 6 in length.

function CheckPassword(password)
{
	if (password.value.length >=6) {
		var addLet = 0;
		for (var i =0; i < password.value.length; i++) {
			if (isNaN(password.value[i]))
				addLet++;
		}
		if (addLet == password.value.length)
		{
			alert("Please enter a password that contains at least 1 aplha/numeric character");
		} else
			return true;
	} else
		alert("Please enter a password that is at least 6 characters long");
	return false;
}

Here on the change password, I am making sure that the first password conforms to the above function check and also that the two passwords are the same in value.

function CheckChangePasswords()
{
	if (CheckPassword(document.getElementById("password1"))) 
	{
		if (document.getElementById("password1").value == document.getElementById("password2").value)
			return true;
		else
			alert("Passwords do not match");
	}
	return false;
}

Next is the actual php pages that the user will interact with.

Stock Name	Quantity	Price of Stock	Value	Sell
\"{$_SERVER["PHP_SELF"]}?stock={$theStocks[0]}\">{$theStocks[0]}	{$theStocks[1]}	{$theStocks[2]}	". number_format($theStocks[2] * $theStocks[1],2)."	\"checkbox\" value=\"{$theStocks[0]}\" name=\"remove_{$theStocks[0]}\"/>
\"2\">	Total value	".number_format($totalValue,2)."

Date	Title/Link
{$stockDetailsArray[$i]["Date"]}	\"{$stockDetailsArray[$i]["Link"]}\" target=\"_blank\">{$stockDetailsArray[$i]["Title"]}"; } echo "