// SPDX-FileCopyrightText: 2026 Kerstin Humm <kerstin@erictapen.name>
//
// SPDX-License-Identifier: AGPL-3.0-or-later

import { AnnotatedWrapper, Rule } from "../types.js";
import { buildReference } from "../utils.js";

export default {
  name: "timezone attribute",
  validate: (self) => {
    // This seems to differ slightly between Firefox (Web) and NodeJS. For example the UTC value was only valid in Firefox.
    // Also this requires Intl to be added to compilerOptions.lib in tsconfig.
    // There might be better ways to do this.
    const ianaTimezones = Intl.supportedValuesOf("timeZone");

    let result = new AnnotatedWrapper();

    if ("timezone" in self) {
      result.assertString(self, ["timezone"], {
        kind: "Violation",
        id: "TimezoneNotAString",
        text: `The timezone ${self["timezone"]} is not a string`,
        reference: buildReference({ anchor: "time-zone" }),
      });
    } else {
      result.annotateAt([], {
        kind: "Note",
        id: "NoTimezone",
        text: "The event might need a timezone",
        reference: buildReference({
          anchor: "time-zone",
          text:
            "if the Event is primarily conducted in a single specific time-zone, the application SHOULD set the https://w3id.org/fep/8a8e/timezone",
        }),
      });
    }

    if ("timezone" in self && typeof self["timezone"] === "string") {
      if (ianaTimezones.includes(self["timezone"]!)) {
        result.annotateAt(["timezone"], {
          kind: "Correct",
          text: "Valid timezone",
        });
      } else {
        result.annotateAt(["timezone"], {
          kind: "Violation",
          id: "InvalidTimezone",
          text: `The timezone ${self["timezone"]} is not a valid IANA timezone`,
          reference: buildReference({
            anchor: "time-zone",
            text:
              "In case the https://w3id.org/fep/8a8e/timezone property is specified it MUST be a specific IANA time zone identifier included in the IANA Time Zone Database",
          }),
        });
      }
    } else {
    }
    return result.value;
  },
  tests: [
    {
      value: { "timezone": null },
      result: { annotations: [], object: { "timezone": "TimezoneNotAString" } },
    },
    {
      value: {},
      result: { annotations: ["NoTimezone"], object: {} },
    },
    {
      value: { "timezone": "Pacific/Honolulu" },
      result: { annotations: [], object: { "timezone": "Correct" } },
    },
    {
      value: { "timezone": "not an actual IANA timezone" },
      result: { annotations: [], object: { "timezone": "InvalidTimezone" } },
    },
  ],
} satisfies Rule;