import type { TSchema } from "@sinclair/typebox";

import { Type } from "@sinclair/typebox";

import { variableValueSchema } from "./fragments";

type SchemaKind = "authoring" | "normalized";

const LOG_LEVELS = ["trace", "debug", "info", "warn", "error", "fatal"] as const;
const ROTATION_FREQUENCIES = ["hourly", "daily", "weekly"] as const;

const sizeSchema = Type.Union([Type.String(), Type.Integer({ minimum: 0 })]);

export function createAuthoringConfigSchema(): TSchema {
  return createConfigSchemaForKind("authoring");
}

export function createExternalConfigSchema(): Record<string, unknown> {
  return {
    ...cloneSchema(createAuthoringConfigSchema()),
    $id: "https://app.local/config.schema.json",
    $schema: "http://json-schema.org/draft-07/schema#",
  };
}

export function createNormalizedConfigSchema(): TSchema {
  return createConfigSchemaForKind("normalized");
}

function cloneSchema(schema: TSchema): Record<string, unknown> {
  return JSON.parse(JSON.stringify(schema)) as Record<string, unknown>;
}

function createAuthoringFieldSchema(schema: TSchema): TSchema {
  return Type.Unsafe({ anyOf: [schema, { pattern: "^\\$\\{[^}]+\\}$", type: "string" }] });
}

function createConfigSchemaForKind(kind: SchemaKind): TSchema {
  const properties: Record<string, TSchema> = {
    server: Type.Optional(createServerSchema(kind)),
  };
  if (kind === "authoring") {
    properties["variables"] = Type.Optional(
      Type.Record(Type.String({ pattern: "^[a-zA-Z_][a-zA-Z0-9_]*$" }), variableValueSchema),
    );
  }
  return Type.Object(properties, { additionalProperties: false });
}

function createLoggingSchema(kind: SchemaKind): TSchema {
  const logLevelSchema = Type.Union(LOG_LEVELS.map((l) => Type.Literal(l)) as unknown as [TSchema, ...TSchema[]]);
  const logLevel = kind === "authoring" ? createAuthoringFieldSchema(logLevelSchema) : logLevelSchema;
  const frequency =
    kind === "authoring"
      ? createAuthoringFieldSchema(
          Type.Union(ROTATION_FREQUENCIES.map((f) => Type.Literal(f)) as unknown as [TSchema, ...TSchema[]]),
        )
      : Type.Union(ROTATION_FREQUENCIES.map((f) => Type.Literal(f)) as unknown as [TSchema, ...TSchema[]]);
  const rotationSize = kind === "authoring" ? createAuthoringFieldSchema(sizeSchema) : sizeSchema;
  const rotationMaxFiles =
    kind === "authoring" ? createAuthoringFieldSchema(Type.Integer({ minimum: 1 })) : Type.Integer({ minimum: 1 });

  return Type.Object(
    {
      console: Type.Optional(Type.Object({ level: Type.Optional(logLevel) }, { additionalProperties: false })),
      file: Type.Optional(
        Type.Object(
          {
            level: Type.Optional(logLevel),
            path: Type.Optional(Type.String({ minLength: 1 })),
            rotation: Type.Optional(
              Type.Object(
                {
                  frequency: Type.Optional(frequency),
                  maxFiles: Type.Optional(rotationMaxFiles),
                  size: Type.Optional(rotationSize),
                },
                { additionalProperties: false },
              ),
            ),
          },
          { additionalProperties: false },
        ),
      ),
      level: Type.Optional(logLevel),
    },
    { additionalProperties: false },
  );
}

function createServerSchema(kind: SchemaKind): TSchema {
  return Type.Object(
    {
      listen: Type.Optional(
        Type.Object(
          {
            host: Type.Optional(Type.String()),
            port: Type.Optional(integerForKind(kind, { maximum: 65535, minimum: 0 })),
          },
          { additionalProperties: false },
        ),
      ),
      logging: Type.Optional(createLoggingSchema(kind)),
      storage: Type.Optional(
        Type.Object(
          {
            dataDir: Type.Optional(Type.String()),
          },
          { additionalProperties: false },
        ),
      ),
    },
    { additionalProperties: false },
  );
}

function integerForKind(kind: SchemaKind, options?: Parameters<typeof Type.Integer>[0]): TSchema {
  const schema = Type.Integer(options);
  return kind === "authoring" ? createAuthoringFieldSchema(schema) : schema;
}