{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://raw.githubusercontent.com/api-evangelist/tetra-tech/main/json-schema/tetra-tech-water-quality-schema.json",
  "title": "Water Quality Sample",
  "description": "Schema representing a water quality sample collected as part of Tetra Tech environmental monitoring projects using the Cosmos platform or baytrends analysis tools.",
  "type": "object",
  "required": ["id", "stationId", "collectionDate", "parameters"],
  "properties": {
    "id": {
      "type": "string",
      "description": "Unique sample identifier."
    },
    "stationId": {
      "type": "string",
      "description": "Monitoring station identifier."
    },
    "stationName": {
      "type": "string",
      "description": "Human-readable name of the monitoring station."
    },
    "collectionDate": {
      "type": "string",
      "format": "date-time",
      "description": "Date and time of sample collection."
    },
    "collectedBy": {
      "type": "string",
      "description": "Name or ID of the field technician who collected the sample."
    },
    "location": {
      "type": "object",
      "description": "GPS coordinates of the sample collection point.",
      "required": ["latitude", "longitude"],
      "properties": {
        "latitude": { "type": "number" },
        "longitude": { "type": "number" },
        "datum": { "type": "string", "default": "WGS84" }
      }
    },
    "parameters": {
      "type": "array",
      "description": "Measured water quality parameters.",
      "items": {
        "type": "object",
        "required": ["name", "value", "unit"],
        "properties": {
          "name": {
            "type": "string",
            "description": "Parameter name (e.g., pH, dissolved oxygen, turbidity, nitrate)."
          },
          "value": {
            "type": "number",
            "description": "Measured parameter value."
          },
          "unit": {
            "type": "string",
            "description": "Unit of measurement (e.g., mg/L, NTU, su)."
          },
          "method": {
            "type": "string",
            "description": "Analytical method used."
          },
          "qualifier": {
            "type": "string",
            "description": "Data qualifier flag (e.g., U for non-detect, J for estimated)."
          }
        }
      }
    },
    "labId": {
      "type": "string",
      "description": "Laboratory identifier that analyzed the sample."
    },
    "projectId": {
      "type": "string",
      "description": "Associated Tetra Tech project identifier."
    },
    "tags": {
      "type": "array",
      "items": { "type": "string" }
    },
    "created": { "type": "string", "format": "date-time" }
  }
}