TypeSchemaSample.ts

type Extract<Type, Union> = Type extends Union ? Type : never;

export type TypeSchema<A> =
    TypeSchemaInvariantMap<unknown, A> |
    TypeSchemaRecursive<A> |
    { type: "MaybeUndefined", elemTypeSchema: TypeSchema<NonNullable<A>>, } | (
    A extends ({ has: true, value: unknown, } | { has: false, }) ? { type: "Optional", elemTypeSchema: TypeSchema<Extract<A, { value: unknown, }>["value"]>, } :
    A extends boolean ? { type: "Boolean", } :
    A extends number ? { type: "Number", } :
    A extends string ? { type: "String", possibleValues?: string[], } :
    A extends any[] ? { type: "Array", elemTypeSchema: TypeSchema<A[number]>, } :
    A extends { type: string } ? { type: "Union", parts: { [key in Extract<A,{ type: string, }>["type"]]: PropertiesSchema2<Omit<Extract<A, { type: key, }>, "type">> } } :
    never
) | (
    A extends any ? (
        {
            type: "Object",
            properties: PropertiesSchema2<A>,
        } |
        { type: "Json", }
    ) :
    never
);

type TypeSchemaInvariantMap<A,B> = {
    type: "InvMap",
    typeSchema: TypeSchema<A>,
    fn1: (a: A) => B,
    fn2: (b: B) => A,
};

type TypeSchemaRecursive<A> = {
    type: "Recursive",
    typeSchema: () => TypeSchema<A>,
};