Recursive CTE - Updating nodes in SQL Server - sql-server

Question

I have some main tests. Each of these main tests consist on other tests. Each of these tests consists on other tests and so on. See below the trees as an example.
Main Test 1
ID:1
/ | \
/ | \
+ o +
Test Test Test
ID:2 ID:3 ID:4
/ \ / \
/ \ / \
+ o + o
Test Test Test Test
ID:5 ID:6 ID:7 ID:8
| / \
| / \
o o o
Test Test Test
ID:12 ID:9 ID:10
Main Test 2
ID:2
/ \
/ \
+ +
Test Test
ID:3 ID:8
/ | \
/ | \
o o o
Test Test Test
ID:5 ID:10 ID:7
Symbols:
'o' are leafs
'+' are parents
Main Test 1 and Main Test 2 are main tests (root tests).
Within each main test, ids for tests are unique, but ids tests within a main test can be repeated for within another main tests as above trees show.
I have an input table, let's say, "INPUT" with below columns:
ID_MainTest | ID_TEST | PASSED
With this input table we indicate which tests for each main test are passed.
Also we have another table that contains above trees representation into table, let's say table "Trees":
ID_MainTest | ID_TEST | PARENT_ID_TEST
Finally we have another table, let's say table "TESTS", which contains all the tests which indicates the current result (PENDING,FAILED,PASSED) for each test:
ID_MainTest | ID_TEST | RESULT
So suppose tables content are:
INPUT table (ID_MainTest and ID_Test are primary keys):
ID_MainTest | ID_TEST | PASSED
1 4 1
1 5 1
1 6 1
1 2 1
1 3 1
2 3 1
TREES table (ID_MainTest and ID_Test are primary keys):
ID_MainTest | ID_TEST | PARENT_ID_TEST
1 2 NULL
1 3 NULL
1 4 NULL
1 5 2
1 6 2
1 7 4
1 8 4
1 12 5
1 9 7
1 10 7
2 3 NULL
2 8 NULL
2 5 3
2 10 3
2 7 3
TESTS table (ID_MainTest and ID_Test are primary keys):
ID_MainTest | ID_TEST | RESULT
1 2 PENDING
1 3 FAILED
1 4 FAILED
1 5 PASSED
1 6 PENDING
1 7 PASSED
1 8 FAILED
1 12 PASSED
1 9 PASSED
1 10 PENDING
2 3 PENDING
2 8 FAILED
2 5 PASSED
2 10 PENDING
2 7 PENDING
The functionality is the following:
A test (those indicated in input table) will be switch to passed if and only if all its children figure as passed. If any of its children (or descendants) is failed, then parent will be set/switch to failed despite of indicated as passed in input table.
If test is indicated to be passed from input table, all its children (and descendants) will be set/switch to passed from the parent to the leafs when possible: Children (and descendants) may only be switch to passed if they figure as pending. If a child (or descendant) figures as failed it cannot be switch to passed (it keeps as failed). Also if a child (or descendant) already figures as passed it is not necessary to switch again to passed, it will be kept.
Parent indicated as passed in input table, can be switch to passed if
all its descendants figure as passed (independently if this parent
figures as failed or pending in the tests table, this is an
exception).
So taken into account the functionality and tables content above indicated I would like to obtain below result table with only the tests we have tried to switch to passed (successfully or not), switched to passed, or maintained to failed or passed, including those indicated in input table:
(ID_MainTest and ID_Test are primary keys):
ID_MainTest | ID_TEST | RESULT
1 2 PASSED
1 3 PASSED
1 4 FAILED
1 5 PASSED
1 6 PASSED
1 7 PASSED
1 8 FAILED
1 12 PASSED
1 9 PASSED
1 10 PASSED
2 3 PASSED
2 5 PASSED
2 10 PASSED
2 7 PASSED
I provide the initial tables below:
DECLARE #INPUT AS TABLE
(
ID_MainTest int,
ID_TEST int,
PASSED bit
)
INSERT INTO #INPUT VALUES
(1, 4, 1),
(1, 5, 1),
(1, 6, 1),
(1, 2, 1),
(1, 3, 1),
(2, 3, 1)
DECLARE #TREES AS TABLE
(
ID_MainTest int,
ID_TEST int,
PARENT_ID_TEST int
)
INSERT INTO #TREES VALUES
(1, 2, NULL),
(1, 3, NULL),
(1, 4, NULL),
(1, 5, 2),
(1, 6, 2),
(1, 7, 4),
(1, 8, 4),
(1, 12, 5),
(1, 9, 7),
(1, 10, 7),
(2, 3, NULL),
(2, 8, NULL),
(2, 5, 3),
(2, 10, 3),
(2, 7, 3)
DECLARE #TESTS AS TABLE
(
ID_MainTest int,
ID_TEST int,
RESULT NVARCHAR(50)
)
INSERT INTO #TESTS VALUES
(1, 2, 'PENDING'),
(1, 3, 'FAILED'),
(1, 4, 'FAILED'),
(1, 5, 'PASSED'),
(1, 6, 'PENDING'),
(1, 7, 'PASSED'),
(1, 8, 'FAILED'),
(1, 12, 'PASSED'),
(1, 9, 'PASSED'),
(1, 10, 'PENDING'),
(2, 3, 'PENDING'),
(2, 8, 'FAILED'),
(2, 5, 'PASSED'),
(2, 10, 'PENDING'),
(2, 7, 'PENDING')