includes/splitter.inc

   1 <?php
   2 require_once($path_to_root.'/'.'includes/date_functions.inc');
   3 class SqlSet {
   4         protected $pairs;
   5         function __construct($set=null) {
   6                 $this->pairs = $set ?  array_merge($set->pairs) : array();
   7         }
   8
   9         function add($value, $field, $quote=true) {
  10                 if($value !=null)  {
  11                         array_push($this->pairs, $quote ? "$field = '$value'" : "$field = $value");
  12                 }
  13
  14                 return $this;
  15         }
  16
  17         function addDate($date, $field) {
  18                 return $this->add(date2sql($date), $field);
  19         }
  20
  21         function toString() {
  22                 return implode(', ', $this->pairs);
  23         }
  24
  25 }
  26 class Split {
  27         public $start_date;
  28         public $end_date;
  29         public $quantity=0;
  30         public $quantity_dispatched=0;
  31
  32
  33         function __construct($start_date, $period=null) {
  34                         $this->start_date = $start_date;
  35                         $this->end_date = $start_date;
  36                         if($period) $this->extend($period);
  37         }
  38
  39         function extend($days) {
  40                         $this->end_date = add_days($this->end_date, $days);
  41         }
  42 }
  43
  44 class Splitter {
  45         public $detail_ids = array() ;
  46         public $start_date;
  47         public $end_date;
  48         public $start_offset;
  49         public $end_offset;
  50         protected $days;
  51         public $max_quantity;
  52
  53         public function __construct(array $data) {
  54                 $this->detail_ids = array();
  55                 foreach($data['detail'] as $detail_id => $detail) {
  56                         array_push($this->detail_ids, $detail_id);
  57                 }
  58                 $this->start_date = $data['start_date'];
  59                 $this->end_date = $data['end_date'];
  60                 $this->start_offset = $data['start_offset'];
  61                 $this->end_offset = $data['end_offset'];
  62                 $this->days = date_diff2($this->end_date, $this->start_date, 'd');
  63
  64                 $this->max_quantity = $data['max_quantity'];
  65         }
  66
  67         protected function loadDetail($detail_id) {
  68                 $sql = "SELECT *
  69                                                 FROM ".TB_PREF."sales_order_details
  70                                                 WHERE id = $detail_id";
  71                 $result = db_query($sql);
  72                 return db_fetch($result);
  73         }
  74
  75         public function splitAll() {
  76                 $ok =  true;
  77                 foreach($this->detail_ids as $detail_id) {
  78 display_warning("processing $detail_id");
  79                                 $detail = $this->loadDetail($detail_id);
  80                                 $splits = $this->split($detail);
  81                                 foreach($splits as $split) $this->alterSplit($split);
  82                                 $ok &= $this->saveSplits($detail, $splits);
  83                 }
  84
  85                 return $ok;
  86         }
  87
  88         public function days() {
  89                 return $this->days;
  90         }
  91
  92
  93
  94         /* This function splits on order detail in bits of a specified size.
  95  * Each split  starting at the end time of the previous one.
  96  * the first split starts at the start_date and ends at the end_date.
  97  * The 'splitting' split the whole quantity not only the quantity left to dispatch
  98  * However, fully dispatched split won't be split in real, but merged with the next one
  99  */
 100         public function split($row) {
 101                 $splits = array();
 102                 $quantity = $row['quantity'];
 103                 $quantity_sent = $row['qty_sent'];
 104
 105                 /* Check if the item has been fully dispatched.
 106                  * If so,  there is no need to do anything.
 107                  */
 108                 if($quantity_sent >= $quantity) return $splits;
 109
 110                 // determine the number of split needed. This will give us the lenght of a split.
 111                 $nsplit = ceil($quantity/$this->max_quantity);
 112
 113                 $period = $this->days/$nsplit;
 114
 115                 array_push($splits, $split = new Split($this->start_date, $period));
 116                 $split->quantity_dispatched = $quantity_sent;
 117                 $split_quantity = min($quantity, $this->max_quantity);
 118                 while($split_quantity > 0) {
 119                                         $split->quantity += $split_quantity;
 120                                 // Check if the split has been entirely dispatch or not.
 121                                 if($split->quantity_dispatched > $split->quantity) {
 122                                         //extend the split
 123                                         $split->extend($period);
 124                                 }
 125                                 else {
 126                                         // create a new split
 127                                         array_push($splits, $split = new Split($split->end_date, $period));
 128
 129                                 }
 130                                 $quantity -= $split_quantity;
 131                                 $split_quantity = min($quantity, $this->max_quantity);
 132                 }
 133
 134                 // We need to remove the last split if it's empty
 135                 if($split->quantity == 0) array_pop($splits);
 136                 return $splits;
 137         }
 138
 139         function alterSplit($split) {
 140                 foreach(explode(' ', 'start end') as $att) {
 141                         $date = "${att}_date";
 142                         $offset = "${att}_offset";
 143                         if($this->$offset === null || $this->$offset === "") {
 144                                 $split->$date = null;
 145                         }
 146                         else {
 147                                 $split->$date = add_days($split->$date, $this->$offset);
 148                         }
 149                 }
 150         }
 151
 152         public function saveSplits($detail, $splits) {
 153                 if(empty($splits)) return true;
 154
 155                 $detail_id = $detail['id'];
 156                 $priority = $detail['priority'];
 157                 $priority_offset = 1;
 158                 $order_no = $detail['order_no'];
 159                 $trans_type = $detail['trans_type'];
 160
 161                 /* We need to update the first one (as it exists already in the database)
 162                  * but insert the following one.
 163                  */
 164                 $first = array_shift($splits);
 165                 $set = new SqlSet();
 166                 $set->addDate($first->start_date, 'hold_until_date')
 167                                 ->addDate($first->end_date, 'expiry_date')
 168                                 ->add($first->quantity, 'quantity', false);
 169         display_warning($set->toString());
 170                 db_query("UPDATE ".TB_PREF."sales_order_details
 171                                                         SET {$set->toString()}
 172                                                         WHERE id = $detail_id", "Problem splitting order details $detail_id");
 173
 174                 // Compute common field for each split
 175                 $common_set  = new SqlSet();
 176                 $common_set->add($order_no, 'order_no', false)
 177                                 ->add($trans_type, 'trans_type')
 178                                 ->add($detail['required_date'], 'required_date')
 179                                 ->add($detail['comment'], 'comment')
 180                                 ->add($detail['stk_code'], 'stk_code')
 181                                 ->add($detail['description'], 'description')
 182                                 ->add($detail['unit_price'], 'unit_price', false)
 183                                 ->add($detail['discount_percent'], 'discount_percent', false);
 184
 185                 foreach($splits as $split) {
 186                         $set = new SqlSet($common_set);
 187                         $set->addDate($split->start_date, 'hold_until_date')
 188                                 ->addDate($split->end_date, 'expiry_date')
 189                                 ->add($split->quantity, 'quantity', false);
 190         display_warning($set->toString());
 191                 db_query("INSERT INTO ".TB_PREF."sales_order_details
 192                                                         SET {$set->toString()}
 193                                                         , priority = '$priority' + INTERVAL ${priority_offset} second"
 194                                                  ,"Problem spliting order details $detail_id");
 195                                 $priority_offset++;
 196                 }
 197
 198                 return true;
 199
 200
 201         }
 202
 203 }
 204 ?>