{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://artframe.mlynn.dev/widgets/widget.schema.json",
  "title": "ArtFrame widget",
  "description": "An ArtFrame HUD widget, spec version 1. See SPEC.md.",
  "type": "object",
  "required": ["spec", "id", "name", "layout"],
  "additionalProperties": false,
  "patternProperties": { "^x-": {} },
  "properties": {
    "$schema": { "type": "string" },
    "spec": { "const": 1 },
    "id": { "type": "string", "pattern": "^[a-z0-9][a-z0-9._-]{0,63}$" },
    "name": { "type": "string", "minLength": 1 },
    "description": { "type": "string" },
    "icon": { "type": "string", "description": "An SF Symbol name, for the Mac app" },
    "author": { "type": "string" },
    "version": { "type": "string" },
    "homepage": { "type": "string" },
    "size": { "enum": ["small", "large", "wide"], "default": "small" },
    "card": { "type": "boolean", "default": true },
    "weight": { "type": "number", "minimum": 0.25, "maximum": 4, "default": 1 },
    "title": { "$ref": "#/$defs/template" },
    "settings": { "type": "array", "items": { "$ref": "#/$defs/setting" } },
    "data": {
      "type": "object",
      "description": "At most 6 sources with \"source\": \"http\" (SPEC.md Limits); built-in providers don't count. JSON Schema can't count only the HTTP ones, so the checker and the apps enforce it.",
      "propertyNames": { "pattern": "^[A-Za-z][A-Za-z0-9_]{0,39}$" },
      "additionalProperties": { "$ref": "#/$defs/source" }
    },
    "needs": {
      "type": "array",
      "items": {
        "type": "object",
        "required": ["unless", "message"],
        "additionalProperties": false,
        "properties": { "unless": { "$ref": "#/$defs/expression" }, "message": { "$ref": "#/$defs/template" } }
      }
    },
    "layout": { "$ref": "#/$defs/node" }
  },
  "$defs": {
    "expression": { "type": "string", "description": "A bare expression, e.g. data.q.quotes or !layout.compact" },
    "template": { "type": "string", "description": "Text with {{ expression }} holes" },
    "number": { "oneOf": [{ "type": "number" }, { "$ref": "#/$defs/template" }] },
    "boolean": { "oneOf": [{ "type": "boolean" }, { "$ref": "#/$defs/template" }] },
    "color": {
      "description": "text, muted, accent, up, down, #RRGGBB, #AARRGGBB, or a template giving one",
      "type": "string"
    },
    "setting": {
      "type": "object",
      "required": ["key"],
      "properties": {
        "key": { "type": "string", "pattern": "^[A-Za-z][A-Za-z0-9_]{0,39}$" },
        "label": { "type": "string" },
        "type": { "enum": ["text", "number", "toggle", "choice"], "default": "text" },
        "default": {},
        "help": { "type": "string" },
        "secret": { "type": "boolean" },
        "min": { "type": "number" },
        "max": { "type": "number" },
        "options": {
          "type": "array",
          "items": {
            "type": "object",
            "required": ["value"],
            "properties": { "value": {}, "label": { "type": "string" } }
          }
        }
      },
      "allOf": [
        {
          "if": { "properties": { "type": { "const": "choice" } } },
          "then": { "required": ["options"] }
        },
        {
          "if": { "properties": { "secret": { "const": true } }, "required": ["secret"] },
          "then": { "not": { "required": ["default"] }, "properties": { "type": { "const": "text" } } }
        }
      ]
    },
    "source": {
      "type": "object",
      "required": ["source"],
      "properties": {
        "source": { "enum": ["http", "weather", "air", "moon", "markets", "calendar", "headlines"] },
        "url": {
          "$ref": "#/$defs/template",
          "description": "https:// with the site written out, then /, ? or the end before any {{ }}; or a single text setting, {{ settings.feed }}. The site must be a DNS name: no IP addresses, localhost, .local names or link shorteners. Redirects stay on the same host, up to 3.",
          "not": { "pattern": "^https://(\\d{1,3}(\\.\\d{1,3}){3}|localhost|[A-Za-z0-9.-]*\\.(local|localhost))\\.?([:/?#]|$)" },
          "pattern": "^(https://[A-Za-z0-9.-]+(:[0-9]{1,5})?([/?#][^{]*(\\{\\{.*)?)?|\\{\\{\\s*settings\\.[A-Za-z][A-Za-z0-9_]*\\s*\\}\\})$"
        },
        "format": { "enum": ["json", "rss", "text"], "default": "json" },
        "refresh": { "type": "integer", "minimum": 60, "maximum": 86400, "default": 900 },
        "headers": { "type": "object", "additionalProperties": { "$ref": "#/$defs/template" } },
        "loading": { "type": "string" },
        "error": { "type": "string" },
        "optional": { "type": "boolean" }
      },
      "allOf": [
        {
          "if": { "properties": { "source": { "const": "http" } } },
          "then": { "required": ["url"] }
        },
        {
          "$comment": "SPEC.md Limits: a source whose url or headers use hud. or settings. refreshes at most every 300 s.",
          "if": {
            "anyOf": [
              { "properties": { "url": { "pattern": "\\{\\{[^}]*\\b(hud|settings)\\b" } }, "required": ["url"] },
              { "properties": { "headers": { "not": { "additionalProperties": { "not": { "pattern": "\\{\\{[^}]*\\b(hud|settings)\\b" } } } } }, "required": ["headers"] }
            ]
          },
          "then": { "properties": { "refresh": { "minimum": 300 } } }
        }
      ]
    },
    "common": {
      "when": { "$ref": "#/$defs/expression" },
      "flex": { "$ref": "#/$defs/number" },
      "width": { "$ref": "#/$defs/number" },
      "height": { "$ref": "#/$defs/number" },
      "before": { "$ref": "#/$defs/number" }
    },
    "node": {
      "type": "object",
      "required": ["type"],
      "properties": { "type": { "enum": ["column", "row", "list", "text", "label", "clock", "sparkline", "bar", "spacer"] } },
      "allOf": [
        {
          "if": { "properties": { "type": { "enum": ["column", "row"] } } },
          "then": {
            "required": ["children"],
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "children": { "type": "array", "items": { "$ref": "#/$defs/node" } },
              "gap": { "$ref": "#/$defs/number" },
              "align": { "enum": ["start", "center", "end", "baseline"] }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "list" } } },
          "then": {
            "required": ["items", "item"],
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "items": { "$ref": "#/$defs/expression" },
              "item": { "$ref": "#/$defs/node" },
              "as": { "type": "string" },
              "max": { "$ref": "#/$defs/number" },
              "direction": { "enum": ["column", "row"] },
              "gap": { "$ref": "#/$defs/number" },
              "empty": { "$ref": "#/$defs/template" },
              "groupBy": { "$ref": "#/$defs/expression" },
              "header": { "$ref": "#/$defs/node" },
              "groupGap": { "$ref": "#/$defs/number" }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "text" } } },
          "then": {
            "required": ["text"],
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "text": { "$ref": "#/$defs/template" },
              "size": { "$ref": "#/$defs/number" },
              "font": { "enum": ["thin", "light", "regular", "medium"] },
              "color": { "$ref": "#/$defs/color" },
              "lines": { "$ref": "#/$defs/number" },
              "tabular": { "$ref": "#/$defs/boolean" },
              "tracking": { "$ref": "#/$defs/number" },
              "opacity": { "$ref": "#/$defs/number" },
              "align": { "enum": ["start", "center", "end"] }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "label" } } },
          "then": {
            "required": ["text"],
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "text": { "$ref": "#/$defs/template" },
              "color": { "$ref": "#/$defs/color" }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "clock" } } },
          "then": {
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "format": { "$ref": "#/$defs/template" },
              "format24": { "$ref": "#/$defs/template" },
              "size": { "$ref": "#/$defs/number" },
              "font": { "enum": ["thin", "light", "regular", "medium"] },
              "color": { "$ref": "#/$defs/color" },
              "tabular": { "$ref": "#/$defs/boolean" },
              "tracking": { "$ref": "#/$defs/number" },
              "opacity": { "$ref": "#/$defs/number" },
              "align": { "enum": ["start", "center", "end"] }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "sparkline" } } },
          "then": {
            "required": ["points"],
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "points": { "$ref": "#/$defs/expression" },
              "baseline": { "$ref": "#/$defs/expression" },
              "color": { "$ref": "#/$defs/color" }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "bar" } } },
          "then": {
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "color": { "$ref": "#/$defs/color" },
              "radius": { "$ref": "#/$defs/number" }
            },
            "additionalProperties": false
          }
        },
        {
          "if": { "properties": { "type": { "const": "spacer" } } },
          "then": {
            "properties": {
              "type": true, "when": true, "flex": true, "width": true, "height": true, "before": true,
              "size": { "$ref": "#/$defs/number" }
            },
            "additionalProperties": false
          }
        }
      ]
    }
  }
}