{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://openpaintformat.org/schemas/palette/v1/palette.schema.json",
  "title": "Open Paint Format Palette v1 (draft)",
  "description": "A reusable, named set of paints, mixtures, and colors with semantic roles and optional relationships (e.g. a shadow-to-highlight sequence). Embeds the Common document envelope. Unlike a Painting Workflow ('recipe') it is not an ordered process. A palette MUST remain valid with literal paint references and no central catalogue entry or color value. DRAFT: not frozen; see specs/palette/v1/README.md.",
  "type": "object",
  "allOf": [
    { "$ref": "https://openpaintformat.org/schemas/common/v1/common.schema.json#/$defs/envelopeCore" },
    {
      "type": "object",
      "required": ["entries"],
      "properties": {
        "spec": { "const": "palette" },
        "summary": { "type": "string" },
        "intent": {
          "type": "string",
          "description": "Free-text aesthetic or material intent (e.g. 'cold steel with warm rust')."
        },
        "target": {
          "$ref": "https://openpaintformat.org/schemas/common/v1/common.schema.json#/$defs/target"
        },
        "entries": {
          "type": "array",
          "minItems": 1,
          "items": { "$ref": "#/$defs/entry" }
        },
        "relationships": {
          "type": "array",
          "items": { "$ref": "#/$defs/relationship" }
        }
      }
    }
  ],
  "unevaluatedProperties": false,
  "$defs": {
    "colorValue": {
      "$ref": "https://openpaintformat.org/schemas/common/v1/common.schema.json#/$defs/colorValue"
    },
    "paintRef": {
      "$ref": "https://openpaintformat.org/schemas/common/v1/common.schema.json#/$defs/paintRef"
    },
    "mixEntry": {
      "type": "object",
      "additionalProperties": false,
      "required": ["paint", "parts"],
      "properties": {
        "paint": {
          "type": "string",
          "minLength": 1,
          "description": "Anchor into another entry's `ref`."
        },
        "parts": {
          "type": "number",
          "exclusiveMinimum": 0,
          "description": "Author-provided ratio part, relative within one mixture."
        }
      }
    },
    "entry": {
      "type": "object",
      "additionalProperties": false,
      "required": ["name"],
      "description": "A named palette slot. It MUST carry at least one of a paint reference, a literal color, or a mixture.",
      "properties": {
        "name": { "type": "string", "minLength": 1 },
        "ref": {
          "type": "string",
          "minLength": 1,
          "description": "Document-local anchor other entries/relationships can point to. MUST be unique within entries[] (semantic rule entry-ref-unique; JSON Schema cannot express it)."
        },
        "role": {
          "$ref": "https://openpaintformat.org/schemas/common/v1/common.schema.json#/$defs/role"
        },
        "paint": { "$ref": "#/$defs/paintRef" },
        "color": { "$ref": "#/$defs/colorValue" },
        "mix": {
          "type": "array",
          "minItems": 2,
          "items": { "$ref": "#/$defs/mixEntry" },
          "description": "A mixture of two or more entries with author-provided ratios."
        },
        "provenance": {
          "type": "array",
          "items": {
            "$ref": "https://openpaintformat.org/schemas/common/v1/common.schema.json#/$defs/provenanceEntry"
          }
        },
        "note": { "type": "string" }
      },
      "anyOf": [{ "required": ["paint"] }, { "required": ["color"] }, { "required": ["mix"] }]
    },
    "relationship": {
      "type": "object",
      "additionalProperties": false,
      "required": ["type", "sequence"],
      "description": "A relationship between entries, e.g. an ordered shadow-to-highlight sequence.",
      "properties": {
        "type": {
          "type": "string",
          "enum": ["shadow_to_highlight", "analogous", "complementary", "triadic", "custom"]
        },
        "sequence": {
          "type": "array",
          "minItems": 2,
          "items": { "type": "string", "minLength": 1 },
          "description": "Ordered anchors into entries[].ref."
        },
        "note": { "type": "string" }
      }
    }
  }
}