// Critical Path Analysis Query (Optimized)
// Finds the longest path in terms of total duration of jobs.

// 1. Find all potential start nodes first
MATCH (start_node:Job)
WHERE NOT EXISTS((:Job)-[:PRECEDES]->(start_node))

// 2. Find all potential end nodes first
MATCH (end_node:Job)
WHERE NOT EXISTS((end_node)-[:PRECEDES]->(:Job))

// 3. Now, match paths ONLY between the pre-filtered start and end nodes
MATCH path = (start_node)-[:PRECEDES*]->(end_node)

// 4. Calculate the total duration for each path
WITH
    path,
    REDUCE(totalDuration = 0, job IN nodes(path) | totalDuration + job.duration) AS total_duration

// 5. Return the path and its total duration for visualization
RETURN
    path,
    total_duration

// 6. Order by the total duration in descending order to find the longest path
ORDER BY total_duration DESC

// 7. Limit to the top 1 result, which is the Critical Path
LIMIT 1;