# Expanso Pipeline: json-to-csv (CLI mode)
# =========================================
#
# Usage:
#   echo '[{"name":"Alice","age":30}]' | expanso-edge run pipeline-cli.yaml
#
# No API key needed - runs entirely locally.

name: "json-to-csv-cli"
type: pipeline

config:
  input:
    stdin:
      codec: all
      max_buffer: 10485760

  pipeline:
    processors:
      - mapping: |
          meta trace_id = uuid_v4()
          let delimiter = env("DELIMITER").or(",")

          # Parse JSON input
          let data = content().parse_json().catch([])
          let data = if $data.type() == "array" { $data } else { [$data] }

          # Get all unique keys from all objects
          let columns = $data.fold([], pair -> pair.value.keys().or([]).fold(pair.tally, kp -> if kp.tally.contains(kp.value) { kp.tally } else { kp.tally.append(kp.value) }))

          # Build CSV rows
          let header = $columns.join($delimiter)
          let rows = $data.map_each(obj -> $columns.map_each(col -> if obj.get(col).or("").string().contains($delimiter) || obj.get(col).or("").string().contains("\"") {
            "\"" + obj.get(col).or("").string().re_replace_all("\"", "\"\"") + "\""
          } else { obj.get(col).or("").string() }).join($delimiter))

          root.csv = $header + "\n" + $rows.join("\n")
          root.row_count = $data.length()
          root.columns = $columns
          root.metadata = {
            "skill": "json-to-csv",
            "mode": "cli",
            "delimiter": $delimiter,
            "trace_id": meta("trace_id"),
            "timestamp": now()
          }

      - log:
          level: INFO
          message: |
            [json-to-csv] Converted ${! root.row_count } rows (trace: ${! meta("trace_id").slice(0, 8) })

  output:
    stdout:
      codec: json_object