Discussion with @Synar @louisgreiner @emersion @Akctarus

OSRD bugs:

• Roundtrip → one-way, loose an arbitrary one (perhaps the wrong one)
  • When transforming a round trip into a one way, one of the trains is deleted arbitrarily and too fast osrd#13033
• Margins, arbitrary name for roundtrips
  • nge erases margins (and maybe other attributes) osrd#10428
  • NGE : when editing a round trip, too much information is updated osrd#13034
• Duplicating doesn't retain original train data
  • front, nge: populate osrd specific data when duplicating train from nge osrd#14862

Possible solutions:

• ✅ Add more data to NGE events, e.g. a tag explaining what changed
• ❌ Introduce a new event for trainrun changes with only fields which got changed

Focus on trainruns for now.

Tags indicating what changed:

• trainrunSections
  • trainrunSections.nodes (OSRD: path, schedule, reset margins)
  • trainrunSections.times (OSRD: schedule, ⚠️ use old path step IDs
    instead of assuming ${node.id}-${})
  • trainrunSections.numberOfStops (OSRD: no-op)
• name (OSRD: train_name)
• categoryId (OSRD: category)
• frequencyId (OSRD: paced)
• trainrunTimeCategoryId (OSRD: no-op)
• labelIds (OSRD: labels)
• direction (OSRD: special snowflake)
  • For one-way, call generatePathAndSchedule() depending on
    oneWayDirection, then store train schedule
  • For round-trips, create return train schedule based on previous one-way
    train schedule (should be current behavior)

Then add a list of tags to TrainrunOperation, plus a field to indicate
one-way direction:

class TrainrunUpdateOperation extends TrainrunOperation {
  readonly tags: []TrainrunUpdateTag;
  readonly oneWayDirection?: "forward" | "backward";
}

For trainrun duplication:

class TrainrunCreateOperation extends TrainrunOperation {
  readonly duplicatedTrainrunId?: number;
}

Link to design proposal file

No response