import { assertEquals } from "jsr:@std/assert";
import { resolveEventStart, expandRecurrences } from "./icalendar.ts";

Deno.test("resolveEventStart - local date with timezone", async () => {
  const icsEvent = {
    summary: "Test Event",
    start: {
      date: "2025-01-15T12:00:00.000",
      local: {
        date: "2025-01-15T07:00:00.000",
        timezone: "Eastern Standard Time"
      }
    }
  };
  
  const result = await resolveEventStart(icsEvent);
  assertEquals(result?.toISOString(), "2025-01-15T12:00:00.000Z");
});

Deno.test("resolveEventStart - DST check (Summer)", async () => {
  const icsEvent = {
    summary: "Test Event DST",
    start: {
      date: "2025-07-15T11:00:00.000",
      local: {
        date: "2025-07-15T07:00:00.000",
        timezone: "Eastern Standard Time"
      }
    }
  };
  
  const result = await resolveEventStart(icsEvent);
  assertEquals(result?.toISOString(), "2025-07-15T11:00:00.000Z");
});

Deno.test("resolveEventStart - UTC event", async () => {
  const icsEvent = {
    summary: "UTC Event",
    start: {
      date: "2025-01-15T12:00:00.000Z"
    }
  };
  const result = await resolveEventStart(icsEvent);
  assertEquals(result?.toISOString(), "2025-01-15T12:00:00.000Z");
});

Deno.test("expandRecurrences - weekly event", () => {
  const icsEvent = {
    summary: "Weekly Meeting",
    start: "2025-01-01T10:00:00",
    rrule: "FREQ=WEEKLY;COUNT=3;BYDAY=WE"
  };
  
  const results = expandRecurrences(icsEvent, 30);
  assertEquals(results.length, 3);
  assertEquals(results[0].start, "2025-01-01T10:00:00");
  assertEquals(results[1].start, "2025-01-08T10:00:00");
  assertEquals(results[2].start, "2025-01-15T10:00:00");
  assertEquals(results[1].recurrent, true);
});

Deno.test("expandRecurrences - EXDATE exclusion", () => {
  const icsEvent = {
    summary: "Weekly Meeting EXDATE",
    start: "2025-01-01T10:00:00",
    rrule: "FREQ=WEEKLY;COUNT=3;BYDAY=WE",
    exdate: ["2025-01-08T10:00:00"]
  };
  
  const results = expandRecurrences(icsEvent, 30);
  // Should have 2 occurrences (Jan 1, Jan 15), Jan 8 is excluded
  assertEquals(results.length, 2);
  assertEquals(results[0].start, "2025-01-01T10:00:00");
  assertEquals(results[1].start, "2025-01-15T10:00:00");
});

Deno.test("fetchAndParseCalendar - filter cancelled events", async () => {
  // This requires mocking fetch or testing the inner loop logic.
});

Deno.test("resolveEventStart - ignore tzShift", async () => {
  const icsEvent = {
    summary: "Ignore tzShift",
    start: {
      date: "2025-01-15T12:00:00.000",
      local: {
        date: "2025-01-15T07:00:00.000",
        timezone: "Eastern Standard Time"
      }
    }
  };
  
  const result = await resolveEventStart(icsEvent);
  assertEquals(result?.toISOString(), "2025-01-15T12:00:00.000Z");
});

Deno.test("expandRecurrences - custom windowDays", () => {
  const icsEvent = {
    summary: "Daily Meeting",
    start: "2025-01-01T10:00:00",
    rrule: "FREQ=DAILY"
  };
  
  // 7 days window (Jan 1 to Jan 8) should give 8 occurrences if inclusive
  const results = expandRecurrences(icsEvent, 7);
  assertEquals(results.length, 8);
});