// Dynamic Critical Path Analysis Query for Graph Visualization (Pure Cypher, Final & Performant)
// Collects all paths into a single list to ensure full graph rendering in Memgraph Lab.

// Parameter for the scenario ID
// Example: :scenario_id => 'parallel-process'

// 1. Find start nodes for the scenario
MATCH (start_node:Job)
OPTIONAL MATCH (start_node)<-[r_in:PRECEDES {scenario: $scenario_id}]-()
WITH start_node, r_in WHERE r_in IS NULL
MATCH (end_node:Job)
OPTIONAL MATCH (end_node)-[r_out:PRECEDES {scenario: $scenario_id}]->()
WITH start_node, end_node, r_out WHERE r_out IS NULL

// 2. Match all valid paths for the scenario
MATCH path = (start_node)-[rels:PRECEDES*]->(end_node)
WHERE ALL(r IN rels WHERE r.scenario = $scenario_id)

// 3. For each job in the path, calculate its effective duration
WITH path, nodes(path) AS jobs_on_path
UNWIND jobs_on_path AS job
OPTIONAL MATCH (:Scenario {id: $scenario_id})-[m:MODIFIES]->(job)
WITH
    path,
    COLLECT({
        effective_duration: COALESCE(m.new_duration, job.base_duration)
    }) AS jobs_with_deltas

// 4. Calculate total duration for each path
WITH
    path,
    REDUCE(totalDuration = 0, data IN jobs_with_deltas | totalDuration + data.effective_duration) AS total_duration

// 5. Collect all paths, ordered by total_duration, into a single list
WITH COLLECT({path: path, total_duration: total_duration}) AS paths_with_duration
UNWIND paths_with_duration AS p_wd
ORDER BY p_wd.total_duration DESC
RETURN COLLECT(p_wd.path) AS all_paths;