<?php
session_start();
require_once 'db.php';

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    try {
        if (isset($_POST['insert']) && $_POST['insert'] === "insert") {
            if (!isset($_POST['var-1'], $_POST['variation_val'], $_POST['variation_vval'])) {
                throw new Exception("Error: Form data not received!");
            }

            $var = mysqli_real_escape_string($con, $_POST['var-1']);
            $variationValues = json_decode($_POST['variation_val'], true);
            $variationvValues = json_decode($_POST['variation_vval'], true);
            $formattedVariationVals = implode(',', $variationValues);
            $formattedVariationvVals = implode(',', $variationvValues);

            // Check if the variation already exists
            $stmt = $con->prepare("SELECT 1 FROM attributes WHERE VARIATION = ? LIMIT 1");
            $stmt->bind_param('s', $var);
            $stmt->execute();
            $stmt->store_result();

            if ($stmt->num_rows > 0) {
                echo "exists";
            } else {
                // Insert new variation ID, VARIATION, VARIATION_VAL, VARIATION_VVALUE
                $stmt = $con->prepare("INSERT INTO attributes (VARIATION, VARIATION_VAL, VARIATION_VVALUE) VALUES (?, ? , ?)");
                $stmt->bind_param('sss', $var, $formattedVariationVals,$formattedVariationvVals);
                if ($stmt->execute()) {
                    echo "Variation added successfully.";
                } else {
                    throw new Exception("Error inserting variation: " . $stmt->error);
                }
            }
            $stmt->close();
        } 
        elseif (isset($_POST['action']) && $_POST['action'] === "update") {
            if (!isset($_POST['var-1'], $_POST['variation_val'], $_POST['variation_vval'], $_POST['id'])) {
                throw new Exception("Error: Required update data not received!");
            }
        
            $id = intval($_POST['id']);
            $var = mysqli_real_escape_string($con, $_POST['var-1']);
            $variationValues = json_decode($_POST['variation_val'], true);
            $variationvValues = json_decode($_POST['variation_vval'], true);
            $formattedVariationVals = implode(',', $variationValues);
            $formattedVariationvVals = implode(',', $variationvValues);
        
            $stmt = $con->prepare("SELECT 1 FROM attributes WHERE VARIATION = ? AND ID != ? LIMIT 1");
            $stmt->bind_param('si', $var, $id);
            $stmt->execute();
            $stmt->store_result();
        
            if ($stmt->num_rows > 0) {
                echo "exists";
            } else {
                $stmt = $con->prepare("UPDATE attributes SET VARIATION = ?, VARIATION_VAL = ?, VARIATION_VVALUE = ? WHERE ID = ?");
                $stmt->bind_param('sssi', $var, $formattedVariationVals, $formattedVariationvVals, $id);
                if ($stmt->execute()) {
                    echo "Variation updated successfully.";
                } else {
                    throw new Exception("Error updating variation: " . $stmt->error);
                }
            }
            $stmt->close();
        }
        
        elseif (isset($_POST['delete']) && $_POST['delete'] === "delete" && isset($_POST['atid'])) {
            $atid = intval($_POST['atid']);
            
            $con->begin_transaction();
            $stmt = $con->prepare("DELETE FROM attributes WHERE ID = ?");
            $stmt->bind_param("i", $atid);
            
            if ($stmt->execute()) {
                echo "success|Attribute deleted successfully.";
                $con->commit();
            } else {
                $con->rollback();
                throw new Exception("Error deleting attribute: " . $stmt->error);
            }
            $stmt->close();
        } 
       
         else {
            throw new Exception("Error: Invalid request method or missing parameters!");
        }
    } catch (Exception $e) {
        echo "error|" . $e->getMessage();
    }
} else {
    echo "Error: Invalid request method!";
}
?>