import-viaduct-csv

name	import-viaduct-csv
description	Use this skill when the task is to import, map, validate, clean, or normalize viaducttrip.csv-like exports into the trainmap schema. Do not use it for general CSV work unrelated to trip imports.

Goal

Import a viaducttrip.csv-style file into the app safely, preserving original values while mapping rows into the internal trip model.

When to use

Use this skill when:

• a user wants to import viaducttrip.csv
• CSV headers need field mapping
• station names need fuzzy matching
• encoding or operator name cleanup is needed
• unmatched rows need a review flow

When not to use

Do not use this skill for:

• timetable provider adapters
• image export
• map rendering
• general spreadsheet analysis without trip import intent

Required outcomes

• Detect delimiter and text encoding safely
• Suggest column mapping
• Run dry-run validation first
• Preserve original raw row payload
• Record import errors per row
• Separate:
  • matched rows
  • fuzzy-matched rows
  • unmatched rows
  • invalid date/time rows
• Never silently drop rows

Expected fields to look for

Typical viaduct-style columns may include:

• from_station_name
• to_station_name
• departure_date
• departure_time
• arrival_date
• arrival_time
• operator
• train_code
• distance
• tags
• notes

Import strategy

1. Parse raw file safely
2. Normalize text encoding
3. Infer field mapping
4. Validate dates/times
5. Match stations
6. Generate import preview report
7. Commit rows only after preview is accepted

Data model expectations

• imports
• import_rows
• trips
• trip_stops
• trip_geometry_versions

Quality bar

• deterministic parsing
• explicit validation messages
• reproducible import logs
• tests for malformed CSV cases