Convert SQL Query to LINQ query/Lambda expression - sql

Question

I am trying to fetch the results from the DB using the Entity Framework using the below SQL query:
SELECT
Header_Id,
Header_Number, Details_Id,
Details_Header_Date,
(SELECT TOP 1 c.[Comment_Description] FROM [Comment] c
WHERE c.[Comment_CarrierId] = i.[Header_CarrierId] AND c.[Comment_ParentEntityId] = i.[Header_Id]
ORDER BY c.Comment_AddedOn DESC) AS 'HeaderComments',
CONCAT(ht.[HeaderTracker_Reason], ' ', ht.[HeaderTracker_Notes]) AS 'RejectedComments',
at.[InternalComments] AS 'InternalComments',
CASE i.[Header_Status]
WHEN 'Pending' THEN ar.[HeaderTracker_ApprovedLvl] END AS 'ApprovedLevel',
CASE i.[Header_Status]
WHEN 'Pending' THEN ar.[HeaderTracker_DueBy] END AS 'ApprovedDueDate'
FROM [Header] i
LEFT OUTER JOIN [Details] ii
ON i.[Header_Id] = ii.[Details_HeaderId]
INNER JOIN [Carrier] t
ON t.[Carrier_Id] = i.[Header_CarrierId]
LEFT OUTER JOIN [HeaderTracker] ht
ON ht.[HeaderTracker_HeaderId] = i.[Header_Id] AND ht.[HeaderTracker_Type] = 'Rejected'
LEFT OUTER JOIN [AdjustmentTracker] at
ON at.[DetailsId] = ii.[Details_Id]
LEFT OUTER JOIN [HeaderTracker] ar
ON ar.[HeaderTracker_HeaderId] = i.[Header_Id]
AND i.[Header_Status] IN ('Paid', 'Pending', 'Approved', 'PaidWithAdj')
AND ar.[HeaderTracker_IsPending] = 1
The result output should be using LINQ query / LAMBDA expression
The following code is what I tried: (not sure how TOP 1 and CASE would come here + if & is also valid here)
var statuses = new string[] { "Paid", "Pending", "Approved", "PaidWithAdj" };
var hdrdet =
(
from hdr in dbContext.Headers
join det in dbContext.Details on hdr.Header_Id equals det.Header_Id into hdrdet
from h in hdrdet.DefaultIfEmpty()
join carr in dbContext.Carriers on hdr.Carrier_Id equals carr.Header_Carrier_Id into carrs
from c in carrs.DefaultIfEmpty()
join hdrtk in dbContext.HeaderTracker on hdr.Header_Id equals hdrtk.HeaderTracker_HeaderId && hdrtk.HeaderTracker_Type equals "Rejected" into hdrtks
from k in hdrtks.DefaultIfEmpty()
join adjt in dbContext.AdjustmentTracker on adjt.DetailsId equals det.Details_Id into adjts
from a in adjts.DefaultIfEmpty()
join pnd in dbContext.HeaderTracker on pnd.HeaderTracker_HeaderId equals hdr.Header_Id && hdr.Header_Status contains(statuses) && pnd.[HeaderTracker_IsPending] equals 1 into pnds
from p in pnds.DefaultIfEmpty()
select new
{
hdrid = Header_Id,
hdrnumber = Header_Number, Details_Id,
det_date = Details_Header_Date,
reason = HeaderTracker_Reason + ' ' + HeaderTracker_Notes,
intcomments = InternalComments
}
)