Finish up import script incremental and reliability updates

inventory-server/scripts/import/purchase_orders.js

@@ -0,0 +1,82 @@
+// Split into inserts and updates
+const insertsAndUpdates = batch.reduce((acc, po) => {
+  const key = `${po.po_id}-${po.pid}`;
+  if (existingPOMap.has(key)) {
+    const existing = existingPOMap.get(key);
+    // Check if any values are different
+    const hasChanges = columnNames.some(col => {
+      const newVal = po[col] ?? null;
+      const oldVal = existing[col] ?? null;
+      // Special handling for numbers to avoid type coercion issues
+      if (typeof newVal === 'number' && typeof oldVal === 'number') {
+        return Math.abs(newVal - oldVal) > 0.00001; // Allow for tiny floating point differences
+      }
+      // Special handling for receiving_history JSON
+      if (col === 'receiving_history') {
+        return JSON.stringify(newVal) !== JSON.stringify(oldVal);
+      }
+      return newVal !== oldVal;
+    });
+
+    if (hasChanges) {
+      console.log(`PO line changed: ${key}`, {
+        po_id: po.po_id,
+        pid: po.pid,
+        changes: columnNames.filter(col => {
+          const newVal = po[col] ?? null;
+          const oldVal = existing[col] ?? null;
+          if (typeof newVal === 'number' && typeof oldVal === 'number') {
+            return Math.abs(newVal - oldVal) > 0.00001;
+          }
+          if (col === 'receiving_history') {
+            return JSON.stringify(newVal) !== JSON.stringify(oldVal);
+          }
+          return newVal !== oldVal;
+        })
+      });
+      acc.updates.push({
+        po_id: po.po_id,
+        pid: po.pid,
+        values: columnNames.map(col => po[col] ?? null)
+      });
+    }
+  } else {
+    console.log(`New PO line: ${key}`);
+    acc.inserts.push({
+      po_id: po.po_id,
+      pid: po.pid,
+      values: columnNames.map(col => po[col] ?? null)
+    });
+  }
+  return acc;
+}, { inserts: [], updates: [] });
+
+// Handle inserts
+if (insertsAndUpdates.inserts.length > 0) {
+  const insertPlaceholders = Array(insertsAndUpdates.inserts.length).fill(placeholderGroup).join(",");
+  
+  const insertResult = await localConnection.query(`
+    INSERT INTO purchase_orders (${columnNames.join(",")})
+    VALUES ${insertPlaceholders}
+  `, insertsAndUpdates.inserts.map(i => i.values).flat());
+  
+  recordsAdded += insertResult[0].affectedRows;
+}
+
+// Handle updates
+if (insertsAndUpdates.updates.length > 0) {
+  const updatePlaceholders = Array(insertsAndUpdates.updates.length).fill(placeholderGroup).join(",");
+  
+  const updateResult = await localConnection.query(`
+    INSERT INTO purchase_orders (${columnNames.join(",")})
+    VALUES ${updatePlaceholders}
+    ON DUPLICATE KEY UPDATE
+      ${columnNames
+        .filter(col => col !== "po_id" && col !== "pid")
+        .map(col => `${col} = VALUES(${col})`)
+        .join(",")};
+  `, insertsAndUpdates.updates.map(u => u.values).flat());
+  
+  // Each update affects 2 rows in affectedRows, so we divide by 2 to get actual count
+  recordsUpdated += insertsAndUpdates.updates.length;
+}