Provide data lookup for PXSelector - acumatica

Question

I need advice either to convert the SQL to BQL or set the Resultset manipulated by C# code to the PXSelector.
I need to customize the AR Invoice and add 2 custom fields to record the COGS GL account and sub account for the inter company client when the inter company enter this invoice line as a bill. This custom field need to look up all sub accounts that is restricted to this Client's Branch ID and GL account. Basically all system's sub account lookup take care of the restriction group but for the custom fields; a custom PXSelector need to be written for this. Below is the SQL that supplies the require sub accounts but I need to know how to make the SQL query works in Acumatica
-- SQL for the required data
DECLARE #GLAccountCD nvarchar(10) = 'COGS'
DECLARE #BranchCD nvarchar(30) = 'PurchaseBranch'
SELECT *
FROM Sub
where (((CAST(Sub.groupmask as int) & CAST((SELECT GroupMask FROM Account WHERE AccountCD = #GLAccountCD AND CompanyID = 3 AND DeletedDatabaseRecord = 0) AS int)) > 1
AND (CAST(Sub.groupmask as int) & CAST((SELECT GroupMask FROM Branch WHERE BranchCD = #BranchCD AND CompanyID = 3 AND DeletedDatabaseRecord = 0) AS int)) > 1)
OR (Sub.GroupMask = 0 AND Sub.DeletedDatabaseRecord = 0))
AND CompanyID = 3
ORDER BY SubCD
--The below PXSelector provide all sub accounts regard of restriction group,
--I need the PXSelector to use the above SQL Query result
#region UsrAPBIllGLSubAccID
[PXDBInt]
[PXUIField(DisplayName="Bill COGS SubAccount")]
[PXSelector(typeof(Search<Sub.subID, Where<Sub.active, Equal<True>>, OrderBy<Desc<Sub.subCD>>>),
new Type[] {typeof(Sub.subCD),
typeof(Sub.description)},
SubstituteKey = typeof(Sub.subCD)
)]
public virtual int? UsrAPBIllGLSubAccID { get; set; }
public abstract class usrAPBIllGLSubAccID : IBqlField { }
#endregion

Answer 1

I think that would be achievable using the Match BQL clause.
GLAccess.cs file has BQL queries to restrict accounts based on Sub and Branch group mask using Match clause, this would be a good place to investigate:
public PXSelect<Sub> Sub;
protected virtual IEnumerable sub(
)
{
if (Group.Current != null && !String.IsNullOrEmpty(Group.Current.GroupName))
{
bool inserted = (Group.Cache.GetStatus(Group.Current) == PXEntryStatus.Inserted);
foreach (Sub item in PXSelect<Sub,
Where2<Match<Current<PX.SM.RelationGroup.groupName>>,
Or2<Match<Required<Sub.groupMask>>, Or<Sub.groupMask, IsNull>>>>
.Select(this, new byte[0]))
{
if (!inserted || item.Included == true)
{
Sub.Current = item;
yield return item;
}
else if (item.GroupMask != null)
{
PX.SM.RelationGroup group = Group.Current;
bool anyGroup = false;
for (int i = 0; i < item.GroupMask.Length && i < group.GroupMask.Length; i++)
{
if (group.GroupMask[i] != 0x00 && (item.GroupMask[i] & group.GroupMask[i]) == group.GroupMask[i])
{
Sub.Current = item;
yield return item;
}
anyGroup |= item.GroupMask[i] != 0x00;
}
if (!anyGroup)
{
Sub.Current = item;
yield return item;
}
}
}
}
else
{
yield break;
}
}
public PXSelect<Branch> Branch;
protected virtual IEnumerable branch(
)
{
if (Group.Current != null && !String.IsNullOrEmpty(Group.Current.GroupName))
{
bool inserted = (Group.Cache.GetStatus(Group.Current) == PXEntryStatus.Inserted);
foreach (Branch item in PXSelect<Branch,
Where2<Match<Current<PX.SM.RelationGroup.groupName>>,
Or<Match<Required<Branch.groupMask>>>>>
.Select(this, new byte[0]))
{
if (!inserted)
{
Branch.Current = item;
yield return item;
}
else if (item.GroupMask != null)
{
PX.SM.RelationGroup group = Group.Current;
bool anyGroup = false;
for (int i = 0; i < item.GroupMask.Length && i < group.GroupMask.Length; i++)
{
if (group.GroupMask[i] != 0x00 && (item.GroupMask[i] & group.GroupMask[i]) == group.GroupMask[i])
{
Branch.Current = item;
yield return item;
}
anyGroup |= item.GroupMask[i] != 0x00;
}
if (!anyGroup)
{
Branch.Current = item;
yield return item;
}
}
}
}
else
{
yield break;
}
}