{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "urn:opencourse:theme:1.0",
  "title": "OpenCourse theme v1",
  "description": "theme.json at the root of a theme archive. A theme changes how the app looks, never what it does. The app reads leniently - a bad field is dropped with a note - but an author's editor should be told everything, so this schema is strict.",
  "type": "object",
  "required": [
    "format",
    "id",
    "name",
    "appearance",
    "palette"
  ],
  "additionalProperties": false,
  "properties": {
    "$schema": {
      "type": "string"
    },
    "format": {
      "const": 1
    },
    "id": {
      "type": "string",
      "pattern": "^[a-z0-9]+(?:-[a-z0-9]+)*$",
      "maxLength": 64,
      "description": "Portable id. Importing a theme with an id that is already installed offers to replace it."
    },
    "name": {
      "type": "string",
      "minLength": 1,
      "maxLength": 80
    },
    "version": {
      "type": "string",
      "maxLength": 32
    },
    "author": {
      "type": "string",
      "maxLength": 80
    },
    "description": {
      "type": "string",
      "maxLength": 400
    },
    "appearance": {
      "enum": [
        "dark",
        "light"
      ],
      "description": "Which way the window, native controls, code highlighting and derived colours lean."
    },
    "preview": {
      "$ref": "#/$defs/imagePath",
      "description": "Shown on the theme's card in Settings."
    },
    "palette": {
      "type": "object",
      "required": [
        "background",
        "text",
        "accent"
      ],
      "additionalProperties": false,
      "description": "Seeds. Every colour token is derived from these unless `tokens` sets it.",
      "properties": {
        "background": {
          "$ref": "#/$defs/color"
        },
        "text": {
          "$ref": "#/$defs/color"
        },
        "accent": {
          "$ref": "#/$defs/color"
        },
        "muted": {
          "$ref": "#/$defs/color"
        },
        "success": {
          "$ref": "#/$defs/color"
        },
        "danger": {
          "$ref": "#/$defs/color"
        }
      }
    },
    "tokens": {
      "type": "object",
      "description": "Exact values for colour tokens, overriding what the palette derives.",
      "additionalProperties": false,
      "properties": {
        "fg": {
          "$ref": "#/$defs/color"
        },
        "muted": {
          "$ref": "#/$defs/color"
        },
        "bg": {
          "$ref": "#/$defs/color"
        },
        "card": {
          "$ref": "#/$defs/color"
        },
        "accent": {
          "$ref": "#/$defs/color"
        },
        "accent-fg": {
          "$ref": "#/$defs/color"
        },
        "border": {
          "$ref": "#/$defs/color"
        },
        "selected": {
          "$ref": "#/$defs/paint"
        },
        "selected-edge": {
          "$ref": "#/$defs/color"
        },
        "check-accent": {
          "$ref": "#/$defs/color"
        },
        "ok": {
          "$ref": "#/$defs/color"
        },
        "err": {
          "$ref": "#/$defs/color"
        },
        "err-fg": {
          "$ref": "#/$defs/color"
        },
        "chip-bg": {
          "$ref": "#/$defs/color"
        },
        "chip-fg": {
          "$ref": "#/$defs/color"
        },
        "ok-bg": {
          "$ref": "#/$defs/color"
        },
        "ok-border": {
          "$ref": "#/$defs/color"
        },
        "err-bg": {
          "$ref": "#/$defs/color"
        },
        "err-border": {
          "$ref": "#/$defs/color"
        },
        "accent-ring": {
          "$ref": "#/$defs/color"
        },
        "code-bg": {
          "$ref": "#/$defs/color"
        },
        "bubble": {
          "$ref": "#/$defs/color"
        },
        "bubble-border": {
          "$ref": "#/$defs/color"
        },
        "composer-bg": {
          "$ref": "#/$defs/color"
        },
        "scrollbar": {
          "$ref": "#/$defs/color"
        },
        "scrollbar-hover": {
          "$ref": "#/$defs/color"
        },
        "chrome": {
          "$ref": "#/$defs/color"
        },
        "glass": {
          "$ref": "#/$defs/color"
        },
        "popover": {
          "$ref": "#/$defs/color"
        },
        "overlay": {
          "$ref": "#/$defs/color"
        },
        "shadow": {
          "$ref": "#/$defs/color"
        },
        "hover-ring": {
          "$ref": "#/$defs/color"
        },
        "editor-active-line": {
          "$ref": "#/$defs/color"
        },
        "terminal-selection": {
          "$ref": "#/$defs/color"
        }
      }
    },
    "reducedTransparency": {
      "type": "object",
      "description": "Colours used when macOS asks for reduced transparency or more contrast. Translucent surfaces are otherwise composited over the window colour.",
      "additionalProperties": false,
      "properties": {
        "fg": {
          "$ref": "#/$defs/color"
        },
        "muted": {
          "$ref": "#/$defs/color"
        },
        "bg": {
          "$ref": "#/$defs/color"
        },
        "card": {
          "$ref": "#/$defs/color"
        },
        "accent": {
          "$ref": "#/$defs/color"
        },
        "accent-fg": {
          "$ref": "#/$defs/color"
        },
        "border": {
          "$ref": "#/$defs/color"
        },
        "selected": {
          "$ref": "#/$defs/paint"
        },
        "selected-edge": {
          "$ref": "#/$defs/color"
        },
        "check-accent": {
          "$ref": "#/$defs/color"
        },
        "ok": {
          "$ref": "#/$defs/color"
        },
        "err": {
          "$ref": "#/$defs/color"
        },
        "err-fg": {
          "$ref": "#/$defs/color"
        },
        "chip-bg": {
          "$ref": "#/$defs/color"
        },
        "chip-fg": {
          "$ref": "#/$defs/color"
        },
        "ok-bg": {
          "$ref": "#/$defs/color"
        },
        "ok-border": {
          "$ref": "#/$defs/color"
        },
        "err-bg": {
          "$ref": "#/$defs/color"
        },
        "err-border": {
          "$ref": "#/$defs/color"
        },
        "accent-ring": {
          "$ref": "#/$defs/color"
        },
        "code-bg": {
          "$ref": "#/$defs/color"
        },
        "bubble": {
          "$ref": "#/$defs/color"
        },
        "bubble-border": {
          "$ref": "#/$defs/color"
        },
        "composer-bg": {
          "$ref": "#/$defs/color"
        },
        "scrollbar": {
          "$ref": "#/$defs/color"
        },
        "scrollbar-hover": {
          "$ref": "#/$defs/color"
        },
        "chrome": {
          "$ref": "#/$defs/color"
        },
        "glass": {
          "$ref": "#/$defs/color"
        },
        "popover": {
          "$ref": "#/$defs/color"
        },
        "overlay": {
          "$ref": "#/$defs/color"
        },
        "shadow": {
          "$ref": "#/$defs/color"
        },
        "hover-ring": {
          "$ref": "#/$defs/color"
        },
        "editor-active-line": {
          "$ref": "#/$defs/color"
        },
        "terminal-selection": {
          "$ref": "#/$defs/color"
        }
      }
    },
    "increasedContrast": {
      "type": "object",
      "description": "Colours used when macOS asks for more contrast. border, muted and selected-edge are otherwise derived.",
      "additionalProperties": false,
      "properties": {
        "fg": {
          "$ref": "#/$defs/color"
        },
        "muted": {
          "$ref": "#/$defs/color"
        },
        "bg": {
          "$ref": "#/$defs/color"
        },
        "card": {
          "$ref": "#/$defs/color"
        },
        "accent": {
          "$ref": "#/$defs/color"
        },
        "accent-fg": {
          "$ref": "#/$defs/color"
        },
        "border": {
          "$ref": "#/$defs/color"
        },
        "selected": {
          "$ref": "#/$defs/paint"
        },
        "selected-edge": {
          "$ref": "#/$defs/color"
        },
        "check-accent": {
          "$ref": "#/$defs/color"
        },
        "ok": {
          "$ref": "#/$defs/color"
        },
        "err": {
          "$ref": "#/$defs/color"
        },
        "err-fg": {
          "$ref": "#/$defs/color"
        },
        "chip-bg": {
          "$ref": "#/$defs/color"
        },
        "chip-fg": {
          "$ref": "#/$defs/color"
        },
        "ok-bg": {
          "$ref": "#/$defs/color"
        },
        "ok-border": {
          "$ref": "#/$defs/color"
        },
        "err-bg": {
          "$ref": "#/$defs/color"
        },
        "err-border": {
          "$ref": "#/$defs/color"
        },
        "accent-ring": {
          "$ref": "#/$defs/color"
        },
        "code-bg": {
          "$ref": "#/$defs/color"
        },
        "bubble": {
          "$ref": "#/$defs/color"
        },
        "bubble-border": {
          "$ref": "#/$defs/color"
        },
        "composer-bg": {
          "$ref": "#/$defs/color"
        },
        "scrollbar": {
          "$ref": "#/$defs/color"
        },
        "scrollbar-hover": {
          "$ref": "#/$defs/color"
        },
        "chrome": {
          "$ref": "#/$defs/color"
        },
        "glass": {
          "$ref": "#/$defs/color"
        },
        "popover": {
          "$ref": "#/$defs/color"
        },
        "overlay": {
          "$ref": "#/$defs/color"
        },
        "shadow": {
          "$ref": "#/$defs/color"
        },
        "hover-ring": {
          "$ref": "#/$defs/color"
        },
        "editor-active-line": {
          "$ref": "#/$defs/color"
        },
        "terminal-selection": {
          "$ref": "#/$defs/color"
        }
      }
    },
    "window": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "material": {
          "enum": [
            "vibrancy",
            "solid",
            "image"
          ],
          "default": "vibrancy",
          "description": "vibrancy: macOS glass shows through. solid: the window colour. image: a picture behind everything."
        },
        "color": {
          "$ref": "#/$defs/color"
        },
        "image": {
          "type": "object",
          "required": [
            "src"
          ],
          "additionalProperties": false,
          "properties": {
            "src": {
              "$ref": "#/$defs/imagePath"
            },
            "fit": {
              "enum": [
                "cover",
                "contain",
                "tile",
                "stretch"
              ],
              "default": "cover"
            },
            "position": {
              "enum": [
                "center",
                "top",
                "bottom",
                "left",
                "right",
                "top left",
                "top right",
                "bottom left",
                "bottom right"
              ],
              "default": "center"
            },
            "scale": {
              "type": "number",
              "minimum": 0.25,
              "maximum": 4,
              "default": 1,
              "description": "For fit: tile - the picture's own size times this."
            },
            "tint": {
              "$ref": "#/$defs/color",
              "description": "Painted over the picture (under the grain). A translucent tint keeps text readable."
            },
            "blur": {
              "type": "number",
              "minimum": 0,
              "maximum": 40,
              "description": "Blur radius in px."
            },
            "dim": {
              "$ref": "#/$defs/unit",
              "description": "How far the picture fades toward the window colour."
            }
          }
        }
      }
    },
    "grain": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "amount": {
          "$ref": "#/$defs/grainAmount",
          "description": "Opacity of the noise; 0.12 if omitted, 0.2 is the app's own, 0 turns it off."
        },
        "scale": {
          "type": "number",
          "minimum": 0.5,
          "maximum": 3,
          "default": 1,
          "description": "Larger is coarser."
        },
        "texture": {
          "$ref": "#/$defs/imagePath",
          "description": "A picture to tile instead of the generated noise."
        }
      }
    },
    "surfaces": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "titlebar": {
          "type": "object",
          "description": "The bar at the top of the window.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            },
            "grain": {
              "$ref": "#/$defs/grainAmount"
            },
            "image": {
              "$ref": "#/$defs/picture"
            }
          }
        },
        "sidebar": {
          "type": "object",
          "description": "A course's chapter list.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            },
            "grain": {
              "$ref": "#/$defs/grainAmount"
            },
            "image": {
              "$ref": "#/$defs/picture"
            }
          }
        },
        "list": {
          "type": "object",
          "description": "The Library, Coach and user lists.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            },
            "grain": {
              "$ref": "#/$defs/grainAmount"
            },
            "image": {
              "$ref": "#/$defs/picture"
            }
          }
        },
        "sidechat": {
          "type": "object",
          "description": "The side chat panel.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            },
            "grain": {
              "$ref": "#/$defs/grainAmount"
            },
            "image": {
              "$ref": "#/$defs/picture"
            }
          }
        },
        "popover": {
          "type": "object",
          "description": "Menus and the search panel. Colour, grain and blur; no picture.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            },
            "grain": {
              "$ref": "#/$defs/grainAmount"
            },
            "blur": {
              "type": "number",
              "minimum": 0,
              "maximum": 40,
              "description": "Backdrop blur behind menus, in px."
            }
          }
        },
        "reading": {
          "type": "object",
          "description": "The lesson, settings and exercise brief. Always opaque; colour and grain, no picture.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            },
            "grain": {
              "$ref": "#/$defs/grainAmount"
            }
          }
        },
        "code": {
          "type": "object",
          "description": "Code blocks, the editor and the terminal. Always opaque.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            }
          }
        },
        "card": {
          "type": "object",
          "description": "Cards, panels and quiz blocks.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            }
          }
        },
        "chip": {
          "type": "object",
          "description": "Tags, chips and hover states.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            }
          }
        },
        "bubble": {
          "type": "object",
          "description": "Your messages in the side chat.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            }
          }
        },
        "composer": {
          "type": "object",
          "description": "The side chat's message box.",
          "additionalProperties": false,
          "properties": {
            "color": {
              "$ref": "#/$defs/color"
            },
            "opacity": {
              "$ref": "#/$defs/unit"
            }
          }
        }
      }
    },
    "fonts": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "faces": {
          "type": "array",
          "maxItems": 32,
          "items": {
            "type": "object",
            "required": [
              "family",
              "src"
            ],
            "additionalProperties": false,
            "properties": {
              "family": {
                "$ref": "#/$defs/family"
              },
              "src": {
                "type": "string",
                "pattern": "^(?!/)(?!(?:.*/)?\\.\\.(?:/|$))[^\\\\]+\\.(?:woff2|woff|ttf|otf)$",
                "description": "A font file in the archive."
              },
              "weight": {
                "oneOf": [
                  {
                    "type": "integer",
                    "minimum": 1,
                    "maximum": 1000
                  },
                  {
                    "type": "string",
                    "pattern": "^(?:normal|bold|\\d{1,4} \\d{1,4})$"
                  }
                ],
                "description": "400, or a variable font's range \"100 900\"."
              },
              "style": {
                "enum": [
                  "normal",
                  "italic"
                ]
              }
            }
          }
        },
        "ui": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "family": {
              "oneOf": [
                {
                  "$ref": "#/$defs/family"
                },
                {
                  "type": "array",
                  "items": {
                    "$ref": "#/$defs/family"
                  },
                  "minItems": 1,
                  "maxItems": 8
                }
              ]
            },
            "size": {
              "type": "number",
              "deprecated": true,
              "description": "Accepted and ignored: text size is the reader's choice, set beside the lesson."
            },
            "lineHeight": {
              "type": "number",
              "minimum": 1,
              "maximum": 2.2
            }
          }
        },
        "reading": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "family": {
              "oneOf": [
                {
                  "$ref": "#/$defs/family"
                },
                {
                  "type": "array",
                  "items": {
                    "$ref": "#/$defs/family"
                  },
                  "minItems": 1,
                  "maxItems": 8
                }
              ]
            },
            "size": {
              "type": "number",
              "deprecated": true,
              "description": "Accepted and ignored: text size is the reader's choice, set beside the lesson."
            },
            "lineHeight": {
              "type": "number",
              "minimum": 1,
              "maximum": 2.2
            }
          }
        },
        "heading": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "family": {
              "oneOf": [
                {
                  "$ref": "#/$defs/family"
                },
                {
                  "type": "array",
                  "items": {
                    "$ref": "#/$defs/family"
                  },
                  "minItems": 1,
                  "maxItems": 8
                }
              ]
            },
            "weight": {
              "type": "number",
              "minimum": 100,
              "maximum": 900
            },
            "letterSpacing": {
              "type": "number",
              "minimum": -0.1,
              "maximum": 0.3
            }
          }
        },
        "code": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "family": {
              "oneOf": [
                {
                  "$ref": "#/$defs/family"
                },
                {
                  "type": "array",
                  "items": {
                    "$ref": "#/$defs/family"
                  },
                  "minItems": 1,
                  "maxItems": 8
                }
              ]
            },
            "size": {
              "type": "number",
              "deprecated": true,
              "description": "Accepted and ignored: text size is the reader's choice, set beside the lesson."
            }
          }
        },
        "brand": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "family": {
              "oneOf": [
                {
                  "$ref": "#/$defs/family"
                },
                {
                  "type": "array",
                  "items": {
                    "$ref": "#/$defs/family"
                  },
                  "minItems": 1,
                  "maxItems": 8
                }
              ]
            },
            "weight": {
              "type": "number",
              "minimum": 100,
              "maximum": 900
            },
            "letterSpacing": {
              "type": "number",
              "minimum": -0.1,
              "maximum": 0.3
            }
          }
        }
      }
    },
    "logo": {
      "type": "object",
      "required": [
        "mark"
      ],
      "additionalProperties": false,
      "properties": {
        "mark": {
          "$ref": "#/$defs/imagePath",
          "description": "Replaces the mark beside the OpenCourse wordmark. Square; SVG or at least 64px."
        }
      }
    }
  },
  "$defs": {
    "color": {
      "type": "string",
      "maxLength": 64,
      "pattern": "^(?:#(?:[0-9a-fA-F]{3,4}|[0-9a-fA-F]{6}|[0-9a-fA-F]{8})|rgba?\\([^()]*\\)|hsla?\\([^()]*\\)|transparent|black|white)$"
    },
    "paint": {
      "oneOf": [
        {
          "$ref": "#/$defs/color"
        },
        {
          "type": "object",
          "required": [
            "from",
            "to"
          ],
          "additionalProperties": false,
          "properties": {
            "from": {
              "$ref": "#/$defs/color"
            },
            "to": {
              "$ref": "#/$defs/color"
            }
          }
        }
      ]
    },
    "unit": {
      "type": "number",
      "minimum": 0,
      "maximum": 1
    },
    "grainAmount": {
      "type": "number",
      "minimum": 0,
      "maximum": 0.4
    },
    "family": {
      "type": "string",
      "pattern": "^(?:[A-Za-z0-9][A-Za-z0-9 _.-]{0,63}|-apple-system)$"
    },
    "imagePath": {
      "type": "string",
      "pattern": "^(?!/)(?!(?:.*/)?\\.\\.(?:/|$))[^\\\\]+\\.(?:png|jpe?g|webp|gif|svg)$",
      "description": "A picture in the archive, relative to theme.json."
    },
    "picture": {
      "type": "object",
      "required": [
        "src"
      ],
      "additionalProperties": false,
      "properties": {
        "src": {
          "$ref": "#/$defs/imagePath"
        },
        "fit": {
          "enum": [
            "cover",
            "contain",
            "tile",
            "stretch"
          ],
          "default": "cover"
        },
        "position": {
          "enum": [
            "center",
            "top",
            "bottom",
            "left",
            "right",
            "top left",
            "top right",
            "bottom left",
            "bottom right"
          ],
          "default": "center"
        },
        "scale": {
          "type": "number",
          "minimum": 0.25,
          "maximum": 4,
          "default": 1,
          "description": "For fit: tile - the picture's own size times this."
        },
        "tint": {
          "$ref": "#/$defs/color",
          "description": "Painted over the picture (under the grain). A translucent tint keeps text readable."
        }
      }
    }
  }
}