Fix timestamp parsing with momentjs

Author: strawmelonjuice

bun.lockb

@@ -1,3 +1,5 @@
+import gleam/io
+import gleam/string
 import gleeunit
 import gleeunit/should
 
@@ -16,9 +18,16 @@ pub fn hello_world_test() {
 }
 
 // Test timestamp conversion
-pub fn timestamp_to_test() {
-  let time = "2025-01-22T12:12:07+0000"
+pub fn timestamp_to_timestamp_test() {
+  let time = "2025-01-22T12:12:07.001+01:00"
   let parsed = timestamps.parse(time)
   timestamps.create(parsed)
   |> should.equal(time)
 }
+
+// Test timestamp conversion
+pub fn string_to_timestamp_test() {
+  timestamps.parse("2025-01-24 20:51:03 GMT+0100")
+  |> timestamps.create()
+  |> should.equal("2025-01-24T20:51:03.000+01:00")
+}

cynthia_websites_mini_server/test/cynthia_websites_mini_server_test.gleam

@@ -1,13 +1,27 @@
-import plinth/javascript/date
+/// We use the moment.js library to parse and create timestamps.
+/// This is because the JavaScript `Date` object is not capable of parsing timestamps in the ISO 8601 format reliably enough.
+/// This means we also work with `Moment` objects!
+pub type Moment
 
 /// Converts a timestamp from the ISO 8601 date format (EG: 2025-01-22T12:12:07+0000)
 /// To a JavaScript 'date' object, accessible through Plinth.
-@external(javascript, "./timestamps_ffi.mjs", "parse")
-pub fn parse(timestamp: String) -> date.Date
+@external(javascript, "./timestamps_ffi.ts", "parse")
+pub fn parse(timestamp: String) -> Moment
 
 /// Converts a JavaScript 'date' object, accessible through Plinth
 /// To a timestamp in the ISO 8601 date format (EG: 2025-01-22T12:12:07+0000)
 /// This is the inverse of the `parse` function.
-pub fn create(date_object: date.Date) -> String {
-  date.to_iso_string(date_object)
-}
+@external(javascript, "./timestamps_ffi.ts", "create")
+pub fn create(date_object: Moment) -> String
+
+/// Convert a moment object to an epoch timestamp in minutes.
+@external(javascript, "./timestamps_ffi.ts", "to_minutes_since_epoch")
+pub fn to_minutes_since_epoch(moment: Moment) -> Int
+
+/// Convert minutes since epoch to a moment object.
+@external(javascript, "./timestamps_ffi.ts", "from_minutes_since_epoch")
+pub fn from_minutes_since_epoch(minutes: Int) -> Moment
+
+/// Get the current time as a moment object.
+@external(javascript, "./timestamps_ffi.ts", "rn")
+pub fn rn() -> Moment

cynthia_websites_mini_shared/src/cynthia_websites_mini_shared/timestamps.gleam

@@ -0,0 +1,21 @@
+import moment, { type Moment } from "moment";
+
+export function parse(datestr: string) {
+  return moment(datestr, false);
+}
+
+export function create(timestamp: Moment) {
+  return timestamp.toISOString(true);
+}
+
+export function to_minutes_since_epoch(timestamp: Moment): number {
+  return timestamp.unix() / 60;
+}
+
+export function from_minutes_since_epoch(minutes: number): Moment {
+  return moment.unix(minutes * 60);
+}
+
+export function rn(): Moment {
+  return moment();
+}

cynthia_websites_mini_shared/src/cynthia_websites_mini_shared/timestamps_ffi.mjs

@@ -25,6 +25,7 @@
   "dependencies": {
     "autoprefixer": "^10.4.20",
     "daisyui": "^4.12.23",
+    "moment": "^2.30.1",
     "postcss": "^8.5.1",
     "smol-toml": "^1.3.1",
     "sql.js": "^1.12.0",