Finding the best-fit object from an array of objects - php

Question

Given an array in the following structure (although obviously with many more items in it):
Array
(
[0] => stdClass Object
(
[currency] => 1
[role] => 3
[client_company] =>
[client_group] =>
[hourly_rate] => 115.00
)
[1] => stdClass Object
(
[currency] => 1
[role] => 1
[client_company] =>
[client_group] =>
[hourly_rate] => 115.00
)
[2] => stdClass Object
(
[currency] => 1
[role] => 3
[client_company] => 58
[client_group] =>
[hourly_rate] => 110.00
)
)
I'm trying to create a function that will take four parameters:
$role
$currency
$company [optional]
$group [optional]
("groups" are children of "companies": if a group is specified, a parent company will always also be specified)
...and that will return the "hourly rate" value from the item that best fits those parameters, on the basis that:
if $row, $currency, $company and $group are specified:
find a rate that matches the role, currency, company and group.
if there isn't one, find one that matches the role, currency and company
if there isn't one, find one that matches the role and currency
if there isn't one, return FALSE
if just $row, $currency and $company are specified:
find a rate that matches the role, currency and company
if there isn't one, find one that matches the role and currency
if there isn't one, return FALSE
if just $row and $currency are specified:
find a rate that matches the role and currency
if there isn't one, return FALSE
What I've got is below, and it works. However, it's ugly as sin. There must be a more elegant way than just bashing a load of if/else and loops together. However, it's Friday and I've had too much pizza for lunch and my brain has become ensludged with cheese.
Can you help?
$hourly_rate = FALSE;
if ( !empty($group) && !empty($company) ) {
foreach ( $rates_cache as $rate ) {
if ( $rate->currency == $currency && $rate->role == $role && (int) $rate->client_company === (int) $company && (int) $rate->client_group === (int) $group ) {
$hourly_rate = $rate->hourly_rate;
}
}
if ( empty($hourly_rate) ) {
foreach ( $rates_cache as $rate ) {
if ( $rate->currency == $currency && $rate->role == $role && (int) $rate->client_company === (int) $company ) {
$hourly_rate = $rate->hourly_rate;
}
}
}
if ( empty($hourly_rate) ) {
foreach ( $rates_cache as $rate ) {
if ( $rate->currency == $currency && $rate->role == $role ) {
$hourly_rate = $rate->hourly_rate;
}
}
}
}else if ( !empty($company) ) {
foreach ( $rates_cache as $rate ) {
if ( $rate->currency == $currency && $rate->role == $role && (int) $rate->client_company === (int) $company ) {
$hourly_rate = $rate->hourly_rate;
}
}
if ( empty($hourly_rate) ) {
foreach ( $rates_cache as $rate ) {
if ( $rate->currency == $currency && $rate->role == $role ) {
$hourly_rate = $rate->hourly_rate;
}
}
}
}else{
foreach ( $rates_cache as $rate ) {
if ( $rate->currency == $currency && $rate->role == $role ) {
$hourly_rate = $rate->hourly_rate;
}
}
}
return $hourly_rate;

Answer 1

Assumption
I believe your cache is always in the format below
Cache Format:
$cache = array(
0 => (object) (array(
'currency' => 1,
'role' => 3,
'client_company' => '',
'client_group' => '',
'hourly_rate' => '115.00'
)),
1 => (object) (array(
'currency' => 1,
'role' => 1,
'client_company' => '',
'client_group' => '',
'hourly_rate' => '115.00'
)),
2 => (object) (array(
'currency' => 1,
'role' => 3,
'client_company' => 58,
'client_group' => '',
'hourly_rate' => '110.00'
))
);
Your Revised Function
$param = array(
"role" => 1,
"currency" => 1
);
echo find($cache, $param)->hourly_rate;
Function Used
function find($cache, $param) {
$mx = array();
if (! isset($param['role']) || ! isset($param['currency']))
throw new Exception("Missing Role Or Currency");
foreach ( $cache as $k => $r ) {
foreach ( array_keys(array_intersect($param, (array) $r)) as $key ) {
if ($r->{$key} == $param[$key]) {
isset($mx[$k]) ? $mx[$k] ++ : $mx[$k] = 1;
}
}
}
arsort($mx);
return $cache[key($mx)];
}
More Complex: Another Approach
Usage
$param = array(
"role" => 1,
"currency" => 1
);
$process = new Process($cache);
echo $process->find($param)->best()->hourly_rate; // Outputs 115.00
Multiple Results
When find best fit .. there is possibility you would get more than one result
$param = array(
"role" => 3,
"currency" => 1
);
$process = new Process($cache);
var_dump($process->find($param)->results());
Output
array (size=2)
0 =>
object(stdClass)[1]
public 'currency' => int 1
public 'role' => int 3
public 'client_company' => string '' (length=0)
public 'client_group' => string '' (length=0)
public 'hourly_rate' => string '115.00' (length=6)
2 =>
object(stdClass)[3]
public 'currency' => int 1
public 'role' => int 3
public 'client_company' => int 58
public 'client_group' => string '' (length=0)
public 'hourly_rate' => string '110.00' (length=6)
Not getting best result
You can see based on your parameters you are getting 2 if you are looking for cheapest prize and you call
$param = array(
"role" => 3,
"currency" => 1
);
echo Process::quick($cache, $param)->best()->hourly_rate; // returns 115.00 but that is not the cheapest
Resolution
The solution is you can add filter and sort
$param = array(
"role" => 3,
"currency" => 1
);
$sort = function ($a, $b) {
return $a->hourly_rate < $b->hourly_rate ? - 1 : 1;
};
echo Process::quick($cache, $param)->sort($sort)->best()->hourly_rate; // 110
Getting all Related
You can also just loop through all the result and select the columns you want insted of just getting best result
foreach ( Process::quick($cache, $param)->sort($sort)->getColoum("client_company", "hourly_rate") as $result ) {
print_r($result);
}
Output
stdClass Object
(
[client_company] => 58
[hourly_rate] => 110.00
)
stdClass Object
(
[client_company] =>
[hourly_rate] => 115.00
)
Updated Class
To add all this additional functions you need to upgrade your class to
class Process implements JsonSerializable, IteratorAggregate {
private $cache;
private $matrix = array();
private $final = array();
function __construct($cache) {
$this->cache = $cache;
}
function find($param) {
if (! isset($param['role']) || ! isset($param['currency']))
throw new Exception("Missing Role Or Currency");
foreach ( $this->cache as $k => $rate ) {
$keys = array_intersect($param, (array) $rate);
foreach ( array_keys($keys) as $key ) {
if ($rate->{$key} == $param[$key]) {
isset($this->matrix[$k]) ? $this->matrix[$k] ++ : $this->matrix[$k] = 1;
}
}
}
arsort($this->matrix);
$this->matrix = array_keys(array_filter($this->matrix, function ($v) {
return $v >= 2;
}));
$this->final = $this->sortArray($this->cache, $this->matrix);
return $this;
}
public static function quick($cache, $param) {
$process = new Process($cache);
return $process->find($param);
}
public function best() {
reset($this->final);
return empty($this->final) ? : current($this->final);
}
public function results() {
return $this->final;
}
public function limit($length = 0) {
$this->final = array_slice($this->final, 0, $length);
return $this;
}
public function sort(Callable $function) {
usort($this->final, $function);
return $this;
}
public function getColoum() {
$arg = array_flip(func_get_args());
foreach ( $this->final as &$s ) {
foreach ( $s as $k => $v ) {
if (! isset($arg[$k]))
unset($s->{$k});
}
}
return $this;
}
public function getIterator() {
return new ArrayIterator($this->final);
}
public function jsonSerialize() {
return json_encode($this->final);
}
public function __toString() {
return $this->jsonSerialize();
}
private function sortArray(array $array, array $orderArray) {
$ordered = array();
foreach ( $orderArray as $key => $value ) {
array_key_exists($value, $array) and $ordered[$value] = $array[$value];
}
return $ordered;
}
}