{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://metkagram.github.io/data/learning-event.schema.json",
  "title": "Metkagram local learning event",
  "description": "Privacy-safe event record stored only in the learner's browser unless they explicitly export it.",
  "type": "object",
  "additionalProperties": false,
  "required": [
    "schema_version",
    "event_id",
    "event_name",
    "occurred_at",
    "session_id",
    "locale",
    "page",
    "surface"
  ],
  "properties": {
    "schema_version": {
      "const": 1
    },
    "event_id": {
      "type": "string",
      "minLength": 8,
      "maxLength": 80
    },
    "event_name": {
      "type": "string",
      "enum": [
        "lens_analyze",
        "learning_object_open",
        "clinic_feedback_reveal",
        "pack_step_open",
        "transfer_feedback_reveal",
        "export_download"
      ]
    },
    "occurred_at": {
      "type": "string",
      "format": "date-time"
    },
    "session_id": {
      "type": "string",
      "minLength": 8,
      "maxLength": 80
    },
    "locale": {
      "type": "string",
      "enum": [
        "en",
        "ru"
      ]
    },
    "page": {
      "type": "string",
      "pattern": "^/"
    },
    "surface": {
      "type": "string",
      "enum": [
        "lens",
        "clinic",
        "pack",
        "transfer",
        "exports",
        "practice",
        "other"
      ]
    },
    "object_type": {
      "type": "string",
      "enum": [
        "pattern",
        "contrast",
        "drill",
        "pack",
        "transfer",
        "export",
        "none"
      ]
    },
    "object_id": {
      "type": "string",
      "maxLength": 160
    },
    "metadata": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "result_count": {
          "type": "integer",
          "minimum": 0,
          "maximum": 20
        },
        "result_pattern_ids": {
          "type": "array",
          "maxItems": 10,
          "items": {
            "type": "string",
            "pattern": "^[A-Z0-9_-]+$"
          }
        },
        "target_type": {
          "type": "string",
          "enum": [
            "pattern",
            "contrast",
            "drill",
            "pack",
            "transfer",
            "export",
            "other"
          ]
        },
        "target_id": {
          "type": "string",
          "maxLength": 160
        },
        "format": {
          "type": "string",
          "enum": [
            "json",
            "csv",
            "tsv"
          ]
        },
        "direction": {
          "type": "string",
          "enum": [
            "en-de",
            "de-en"
          ]
        }
      }
    }
  }
}