PHP calculations on a price range

[DanielPT]

Hi,
I have no idea about programming but I can follow logic and instructions.
I am a complete newb.
I run an ecommerce store and I am setting up data files that store order data for my accounting program - I download and import the data (txt files) daily.

I have a sales (invoices) file creation script, I have a customer file creation script - Now I want to create a purchases script.

To do this I am modifying the sales script as most of the data can be the same.

I am stuck however on calculating the purchase price from the sale price for insertion into the text file.

(im using oscommerce if that helps)

So the script section for collecting the sale price for the invoices file creation is this -

$product_price = $order->products[$i]['price'];  

What I need it to do is calculate my cost price from the sale price.

To calculate my sell price is easy, I get my cost price and apply a margin to it - as follows

if cost = 0 - 100 then sell price is 1.15
if cost = 100.01 - 200 then sell price is 1.13

and so on (there are about 6 price breaks in my pricing matrix - but you get the idea).

So if my sell price is $80 then my cost is 80 / 1.15

Easy enough right?

So how can I add to the script to calculate my cost price from the sell price and insert that figure into the txt file.
Something like (try not to laugh)

$product_price = $order->products[$i]['price'];  

if $product_price = <80 then /1.15
elseif $product_price = <180 then /1.13
elseif $product_price = <380 then /1.12 

etc etc

If it helps the more of the page script is here

// some info we may need
$customers_id = $customer_id;
$customers_firstname = $order->customer['firstname'];
$customers_lastname = $order->customer['lastname'];
$customers_street_address = $order->customer['street_address'];
$customers_suburb = $order->customer['suburb'];
$customers_city = $order->customer['city'];
$customers_postcode = $order->customer['postcode'];
$customers_state = $order->customer['state'];
$customers_country = $order->customer['country']['title'];
$customers_telephone = $order->customer['telephone'];
$customers_email_address = $order->customer['email_address'];
$customers_address_format_id = $order->customer['format_id'];
$delivery_name = $order->delivery['firstname'] . ' ' . $order->delivery['lastname'];
$delivery_street_address = $order->delivery['street_address'];
$delivery_suburb = $order->delivery['suburb'];
$delivery_city = $order->delivery['city'];
$delivery_postcode = $order->delivery['postcode'];
$delivery_state = $order->delivery['state'];
$delivery_country = $order->delivery['country']['title'];
$delivery_address_format_id = $order->delivery['format_id'];
$payment_method = $order->info['payment_method'];
$cc_type = $order->info['cc_type'];
$cc_owner = $order->info['cc_owner'];
$cc_number = $order->info['cc_number'];
$cc_expires = $order->info['cc_expires'];
$date_purchased = 'now()';
$orders_status = DEFAULT_ORDERS_STATUS_ID;
$comments = $order->info['comments'];
$currency = $order->info['currency'];
$currency_value = $order->info['currency_value'];


// First we setup the format of our transaction header, 
// These can be changed to suit your requirements, but
// read the MYOB docs for more info.
$transaction_header ="LASTNAME\tFIRSTNAME\tADDR1\tADDR2\tADDR3\tADDR4\tTAXINC\tORDERNUM\tORDERDATE\t";  

$transaction_header.="SUPPINV\tSHIPVIA\tPRINTED\tITEMNO\tQTY\tDESC\tPRICE\tINCTAX\t";
$transaction_header.="DISC\tTOTAL\tTAXTOT\tJOB\tCOMMENT\tJNLMEMO\tSFRST\tSLAST\tSHIPDATE\tREF\tTAXCODE\t";
$transaction_header.="NOGSTAMT\tGSTAMT\tLCTAMT\tFRTAMT\tINCTXFRT\tFRTTXCD\tFRTNOGST\tFRTGST\tFRTLCT\t";
$transaction_header.="STATUS\tTERMS\tDISCDYS\tDUEDAYS\tPCNTDISC\tAMTPD\t\n";

$end_order ="\n"; //adds a blank line between orders so MYOB knows when one order stops and a new one starts


 // Now we setup some of the info that we need to send to the file
 $order_date = date('d/m/y');
 $ordernum = $insert_id;  //this will be the order number
 $sale_name = $order->customer['firstname'] . ' ' . $order->customer['lastname']; //matches the format in myob_cust.php
 $shipping = $order->info['shipping_cost'];
 $frtgst = ($shipping / 11);	// Freight GST amount
 $frtnogst = ($frtgst * 9);	// Shipping cost minus GST
 $frtgst = number_format($frtgst, 2, '.', '');
 $nongstc = number_format($nongstc, 2, '.', '');
 $nongst = number_format($nongst, 2, '.', '');
 $frtnogst = number_format($frtnogst, 2, '.', '');
 $inctxprc = number_format($inctxprc, 2, '.', '');
 // Convert transaction amounts from TEP to QB currency, if needed.

 if (CONVERT_MYOB_CURRENCY==1) 
 {  

 $shipping = ($shipping * EXCHANGE_RATE);  

 $shipping_cost = ($shipping_cost * EXCHANGE_RATE);  

 $total_tax = ($total_tax * EXCHANGE_RATE);  

 $total_cost = ($total_cost * EXCHANGE_RATE);}

// more info for the TXT file.
$shipping = number_format($shipping, 2, '.', '');
$shipping_cost = number_format($shipping_cost, 2, '.', '');
$total_cost = number_format($total_cost, 2, '.', '');
$transtotal = $cart->show_total() + $shipping;

// Check if the transaction import file exists;
$oldfile = file_exists ($salefile);

// Open transaction import file for appending, create it if necessary. 1 line for each product.
$fp = fopen($salefile,"a");

if (!$oldfile) 
{  

fputs($fp,$transaction_header);

}    

$lines=$ordernum;
$lines++;
for ($i=0; $i<sizeof($order->products); $i++) {  

$product_name = $order->products[$i]['name'];  

$product_price = $order->products[$i]['price'];  

//$inctxprc = ($product_price * $qty);    

$product_number = $order->products[$i]['model'];  

$class = $order->products[$i]['class'];  

$desc = $order->products[$i]['name'];  

//$vendor = $order->products[$i]['vendor'];  

$qty = $order->products[$i]['qty'];  

$product_id = $order->products[$i]['id'];
//$qty = $qty - ($qty * 2);  // MUST BE NEGATIVE NUMBER, SO 'FLIP' IT  

$total_product_price = ($product_price + $cart->attributes_price($order->products[$i]['id']));
//  $product_tax = tep_get_tax_rate($delivery_values['zone_id'], $order->products[$i]['tax_class_id']);  

$attributes_exist = '0';  

if ($order->products[$i]['attributes']) {    

$attributes_exist = '1';    

reset($order->products[$i]['attributes']);    

while (list($option, $value) = each($order->products[$i]['attributes'])) {      

$attributes = tep_db_query("select popt.products_options_name, poval.products_options_values_name, pa.options_values_price, pa.price_prefix from products_options popt, products_options_values poval, products_attributes pa where pa.products_id = '" . $order->products[$i]['id'] . "' and pa.options_id = '" . $option . "' and pa.options_id = popt.products_options_id and pa.options_values_id = '" . $value . "' and pa.options_values_id = poval.products_options_values_id");      $attributes_values = tep_db_fetch_array($attributes);      

// If there are attributes, we'll simply append the values to the item description      

// on the invoice line      

$memo.= ' ';      

$memo.= $attributes_values['products_options_values_name'];      

$product_price += $attributes_values['options_values_price'];    

}  

}  

if (CONVERT_MYOB_CURRENCY==1) {    

$product_price = ($product_price * EXCHANGE_RATE);    

$total_product_price = ($total_product_price * EXCHANGE_RATE);  

}  

$product_price = number_format($product_price, 2, '.', '');  

$total_product_price = number_format($total_product_price, 2, '.', '');  

$account = $order->products[$i]['accnt'];
$total_product_price = $order->products[$i]['final_price'];  

$ItemCost = $total_product_price * $qty;

/*  

// CHANGE THESE TO SUIT YOUR MYOB TAX CODES  

if ($product_tax == "0.0000") {    $taxcode = "E";  } 
elseif ($product_tax == "0.0000") {    

$taxcode = "G";  } 
else {    $taxcode = "E";  }*/    

$taxcode = "GST";	//Australia has only one tax code


$total = $order->info['total'];
$gst = ($product_price / 10);	//product_price is price with no gst added yet
$gst = number_format($gst, 2, '.', '');

// Let's work out how much GST is paid on the items total (no shipping)
$nongsta = ($total - $shipping);
$nongstc = ($nongsta / 11);
$nongst = ($nongstc * 10);

// Let's work out the GST inclusive product total
$inctxtot1 = $product_price *$qty;
$inctxtot2 = ($inctxtot1 / 10);
$inctxtot = ($inctxtot2 * 11);
$inctxprc1 = ($product_price / 10);
$inctxprc = ($inctxprc1 * 11);

// Let's work out how much GST is paid on the shipping
$fgst = ($shipping / 11);

// Create order lines & write them to file  

$line ="$sale_name\t\t$delivery_name\t$delivery_street_address\t$delivery_suburb\t$delivery_postcode\t$taxinclusive\t$ordernum\t$order_date\t";  

$line.="$suppinv\t$shipvia\t$printed\t$product_number\t$qty\t$desc\t\t$inctxprc\t";  

$line.="$disc\t\t$inctxtot\t\t$comments\t$memo\t$sfirst\t$slast\t$order_date\t$referrer\t$taxcode\t";  

$line.="$sfirst\t$gst\t\t\t$shipping\t$shiptaxcode\t\t$fgst\t\t";  

$line.="$cleared\t$terms\t0\t0\t$discp\t\t\n";  

fputs($fp,$line);  

$lines++;}

// write an end of order line
fputs($fp,$end_order);

fclose($fp);
?>

Thanks for any help.

[bpat1434]

Let me see if I understand you....
You have an item that costs $100.00. So you take a margin of 1.15% off that cost to give you your sale? Wouldn't that be losing money? Anyway, here's how you can do it simply...

<?php

switch(TRUE){
    case (0 <= $cost && $cost < 100):
        $margin = 0.0115;
        break;

case (100 <= $cost && $cost < 200):
    $margin = 0.0113;
    break;

case (200 <= $cost && $cost < 300):
    $margin = 0.111;
    break;

case (300 <= $cost && $cost < 400):
    $margin = 0.109;
    break;

case (400 <= $cost && $cost < 500):
    $margin = 0.107;
    break;
}
$margin_cost = round($cost*$margin, 2);

$sell_price = $cost-$margin_cost;
?>

So here are a few examples....

Cost: $100.00
Margin: 0.0113% ($1.13)
Sell Price: $98.87

Cost: $150.00
Margin: 0.0113% ($1.69)
Sell Price: $148.31

Cost: $75.42
Margin: 0.0115% ($0.87)
Sell Price: $74.55

You can also jsut switch the minus to a plus to add teh margin....

~Brett

[DanielPT]

Let me see if I understand you....
You have an item that costs $100.00. So you take a margin of 1.15% off that cost to give you your sale? Wouldn't that be losing money? Anyway, here's how you can do it simply...

Not quite.
I dont want to go backwards......losing money.....I need to calculate my purchase price from my sale price.
My purchase price is 100
I then *1.15
sell price now $115
to get my buy price I do the oposite
take 115 sell price and divide by margin (1.15)
gives me my buy price (cost price)

Why am I doing this?
I sell goods that I order and ship when I make a sale (drop shipper)

The files for import are created specifically when I make a sale on my site- so at the end of the day I can easily download into my bookkeeping package my sales, customer information and hopefully related purchase orders (to buy the goods).

Hopefully that makes sense.

So as I dont have anywhere to get my buy price from the checkout page on my site, I want to take out the pre determined margin from the "sell price" so as to get my buy price that way.
With the buy price I can create a txt file for my purchase orders.

So I understand your code (correct syntax etc) but how can I implement it into the code that I posted to change my $Product_price value from sell price to buy price?
If I add it directly below

$product_price = $order->products[$i]['price'];  

will it change the $product_price value?

Or do I leave $product_price alone and now call it $cost ?

The reason I ask is the $product_price value undergoes more "processing" (like for taxes etc) throughout the script and I dont want to really change all the code as I am a "basic" individual....

Thanks for the fast reply

[bpat1434]

Okay.... so then the code would be this:

$product_price = $order->products[$i]['price'];  

//$inctxprc = ($product_price * $qty); 
$product_sell = get_sell($product_price); 

Then at the very top of that file, put this:

function get_sell($price){
    switch(TRUE){
        case (0 <= $cost && $cost < 100):
            $margin = 1.15;
            break;

    case (100 <= $cost && $cost < 200):
        $margin = 1.13;
        break;

    case (200 <= $cost && $cost < 300):
        $margin = 1.11;
        break;

    case (300 <= $cost && $cost < 400):
        $margin =1.09;
        break;

    case (400 <= $cost && $cost < 500):
        $margin = 1.07;
        break;
}

$sell = $cost*$margin;
return $sell;
}

Then just add the $product_sell to your txt file and all should be well...

~Brett