fix(i18n): localise medication reminders and dashboard streak per user (#124)

Closes the v3 audit "Locale Mixing" CRIT plus three of the cousin
findings the v1.4 discovery audit added:

1. **`getPhaseMessage` and `getPhaseKeyboard` were German-only.** Every
   medication reminder shipped via Telegram, ntfy, and Web Push read
   "Erinnerung", "Bald fällig", etc. regardless of the recipient's
   locale. This is the user-facing surface most affected by the v3
   "Locale Mixing" finding because the strings hit users on a 15-minute
   cron, not just an admin / settings page they might never open. The
   reminder worker now passes `med.user.locale` through; messages and
   button labels resolve from `messages/{de,en}.json` under
   `medicationReminders.*`. `callback_data` keys stay stable English
   identifiers so the bot dispatcher keeps matching them across locale
   changes.

2. **`/api/dashboard/summary` ships a hard-coded "Tage in Folge" label
   and "Hi, X" salutation.** Both now come from
   `dashboard.streakLabel` / `dashboard.greetingSalutation` resolved
   server-side against the user's locale.

3. **Mixed-locale Zod messages.** `validations/measurement.ts:69` had
   "Wert muss zwischen … liegen" while line 86 had "Value out of
   plausible range" — the response envelope leaked German into English
   sessions and vice versa. `validations/admin.ts` had four German
   messages (web-push subject, Umami URL, Glitchtip DSN, GitHub
   bug-report repo). All now resolve to a single English wording (the
   app is English-first; the German UI translates the field labels
   client-side, the server-side validation message is treated as a
   developer-facing string).

Adds 13 new tests in `reminder-phases.test.ts` covering English,
German, and unknown-locale fallbacks for messages and keyboards;
updates `validations/measurement.test.ts` to match the unified English
message. The audit's remaining items
(`classifications.ts` server-returned EN category strings,
`pulse-targets.ts`, `targets/route.ts` labels,
`/api/admin/notifications/reminder-check`) ride a follow-up i18n PR —
those are admin-only or client-renderable surfaces with lower
user-facing priority.

Tests: 358 → 371 (+13). Typecheck clean. Locale-integrity test still
green.

Co-authored-by: Marc-André Bombeck <noreply@anthropic.com>

messages/de.json

@@ -194,6 +194,8 @@
     },
     "welcomeBack": "{greeting}, willkommen zurück.",
     "welcomeBackWithName": "{greeting} {name}, willkommen zurück.",
+    "greetingSalutation": "Hi, {name}",
+    "streakLabel": "Tage in Folge",
     "weight": "Gewicht",
     "bloodPressure": "Blutdruck",
     "bloodPressureSys": "Blutdruck (Sys)",
@@ -1629,5 +1631,20 @@
     "medicationNotFoundExact": "Medikament nicht gefunden. Bitte Namen exakt wie in HealthLog senden.",
     "helpHeader": "<b>Verfügbare Befehle:</b>",
     "helpBody": "/help — Diese Hilfe anzeigen\n/add — Einnahme erfassen\n/start — Bot starten\n\n<b>Textbefehle:</b>\ngenommen &lt;Name&gt; — Einnahme bestätigen\n\n<b>Über die Buttons in Erinnerungen:</b>\n• Genommen — Einnahme bestätigen\n• 🕐 1h / 🕐 3h — Erinnerung verschieben\n• ⏭ Überspringen — Einnahme überspringen\n• ✓ Bestätigen — Verpasste Einnahme bestätigen"
+  },
+  "medicationReminders": {
+    "phaseGreenTitle": "🟢 Erinnerung: {medName}",
+    "phaseGreenMessage": "🟢 Erinnerung:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nZeitfenster endet in {minutes} Min.",
+    "phaseYellowTitle": "🟡 Bald fällig: {medName}",
+    "phaseYellowMessage": "🟡 Bald fällig:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nNoch {minutes} Min. Zeit.",
+    "phaseOrangeTitle": "🟠 Überfällig: {medName}",
+    "phaseOrangeMessage": "🟠 Überfällig:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nSeit {minutes} Min. überfällig.",
+    "phaseRedTitle": "🔴 Verpasst: {medName}",
+    "phaseRedMessage": "🔴 Verpasst:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nAls verpasst markiert.",
+    "buttonTaken": "Genommen",
+    "buttonConfirm": "✓ Bestätigen",
+    "buttonSnoozeOneHour": "🕐 1h",
+    "buttonSnoozeThreeHours": "🕐 3h",
+    "buttonSkip": "⏭ Überspringen"
   }
 }

messages/en.json

@@ -194,6 +194,8 @@
     },
     "welcomeBack": "{greeting}, welcome back.",
     "welcomeBackWithName": "{greeting} {name}, welcome back.",
+    "greetingSalutation": "Hi, {name}",
+    "streakLabel": "days in a row",
     "weight": "Weight",
     "bloodPressure": "Blood Pressure",
     "bloodPressureSys": "Blood Pressure (Sys)",
@@ -1629,5 +1631,20 @@
     "medicationNotFoundExact": "Medication not found. Please send the name exactly as in HealthLog.",
     "helpHeader": "<b>Available commands:</b>",
     "helpBody": "/help — show this help\n/add — record an intake\n/start — start the bot\n\n<b>Text commands:</b>\ntaken &lt;name&gt; — confirm an intake\n\n<b>Buttons in reminders:</b>\n• Taken — confirm intake\n• 🕐 1h / 🕐 3h — postpone reminder\n• ⏭ Skip — skip intake\n• ✓ Confirm — confirm a missed intake"
+  },
+  "medicationReminders": {
+    "phaseGreenTitle": "🟢 Reminder: {medName}",
+    "phaseGreenMessage": "🟢 Reminder:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nWindow closes in {minutes} min.",
+    "phaseYellowTitle": "🟡 Due soon: {medName}",
+    "phaseYellowMessage": "🟡 Due soon:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\n{minutes} min left.",
+    "phaseOrangeTitle": "🟠 Overdue: {medName}",
+    "phaseOrangeMessage": "🟠 Overdue:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nOverdue by {minutes} min.",
+    "phaseRedTitle": "🔴 Missed: {medName}",
+    "phaseRedMessage": "🔴 Missed:\n<b>{medName}</b> ({doseInfo}, {timeWindow})\nMarked as missed.",
+    "buttonTaken": "Taken",
+    "buttonConfirm": "✓ Confirm",
+    "buttonSnoozeOneHour": "🕐 1h",
+    "buttonSnoozeThreeHours": "🕐 3h",
+    "buttonSkip": "⏭ Skip"
   }
 }

src/app/api/dashboard/summary/route.ts

@@ -15,6 +15,8 @@ import { annotate } from "@/lib/logging/context";
 import { prisma } from "@/lib/db";
 import type { MeasurementType } from "@/generated/prisma/client";
 import { measurementTypeEnum } from "@/lib/validations/measurement";
+import { getServerTranslator } from "@/lib/i18n/server-translator";
+import { defaultLocale, type Locale } from "@/lib/i18n/config";
 
 const SPARK_DAYS = 7;
 const STREAK_WINDOW_DAYS = 365;
@@ -159,8 +161,8 @@ export const GET = apiHandler(async () => {
     ...measurementTypeEnum.options,
   ] as MeasurementType[];
 
-  const [recentMeasurements, todaysIntakes, streakActivity] =
-    await Promise.all([
+  const [recentMeasurements, todaysIntakes, streakActivity] = await Promise.all(
+    [
       prisma.measurement.findMany({
         where: {
           userId: user.id,
@@ -185,10 +187,12 @@ export const GET = apiHandler(async () => {
         },
         select: { takenAt: true, scheduledFor: true },
       }),
-    ]);
+    ],
+  );
 
   const activityDays = new Set<string>();
-  for (const m of recentMeasurements) activityDays.add(berlinDayKey(m.measuredAt));
+  for (const m of recentMeasurements)
+    activityDays.add(berlinDayKey(m.measuredAt));
   // Pull a wider measurement window for the streak so it isn't capped by
   // SPARK_DAYS — but only if the user has any data at all.
   if (recentMeasurements.length > 0) {
@@ -333,16 +337,19 @@ export const GET = apiHandler(async () => {
   ).length;
 
   const greetingName = user.displayName ?? user.username;
+  const locale: Locale =
+    user.locale === "de" || user.locale === "en" ? user.locale : defaultLocale;
+  const t = getServerTranslator(locale).t;
 
   return apiSuccess({
     greeting: {
-      salutation: `Hi, ${greetingName}`,
+      salutation: t("dashboard.greetingSalutation", { name: greetingName }),
       date: now.toISOString(),
     },
     streak: {
       currentDays: streak.currentDays,
       longest: streak.longest,
-      label: "Tage in Folge",
+      label: t("dashboard.streakLabel"),
     },
     compliance: {
       scheduledToday,

src/lib/jobs/__tests__/reminder-phases.test.ts

@@ -0,0 +1,144 @@
+import { describe, it, expect } from "vitest";
+
+import {
+  determinePhase,
+  getPhaseKeyboard,
+  getPhaseMessage,
+  resolvePhaseThresholds,
+  DEFAULT_PHASE_CONFIG,
+} from "../reminder-phases";
+
+describe("determinePhase", () => {
+  const thresholds = resolvePhaseThresholds(DEFAULT_PHASE_CONFIG, 60);
+
+  it("returns RED past the red threshold", () => {
+    expect(determinePhase(-300, 360, thresholds)).toBe("RED");
+  });
+
+  it("returns ORANGE between window end and red", () => {
+    expect(determinePhase(-30, 90, thresholds)).toBe("ORANGE");
+  });
+
+  it("returns YELLOW within yellowMinBefore of window end", () => {
+    expect(determinePhase(20, 40, thresholds)).toBe("YELLOW");
+  });
+
+  it("returns GREEN inside green window when at/after window start", () => {
+    expect(determinePhase(50, 10, thresholds)).toBe("GREEN");
+  });
+
+  it("returns null before window start", () => {
+    expect(determinePhase(80, -20, thresholds)).toBe(null);
+  });
+});
+
+// v1.4 marathon — closes v3 audit "Locale Mixing" CRIT.
+// Reminder messages must follow the user's stored locale, not always
+// German. callback_data values are stable English identifiers and stay
+// untranslated regardless of UI locale.
+describe("getPhaseMessage — localised", () => {
+  it("uses German message + title for de locale", () => {
+    const result = getPhaseMessage(
+      "GREEN",
+      "Ramipril",
+      "10mg",
+      "08:00–09:00",
+      45,
+      "de",
+    );
+    expect(result.title).toBe("🟢 Erinnerung: Ramipril");
+    expect(result.message).toContain("Zeitfenster endet in 45 Min.");
+    expect(result.message).toContain("<b>Ramipril</b>");
+  });
+
+  it("uses English message + title for en locale", () => {
+    const result = getPhaseMessage(
+      "YELLOW",
+      "Ramipril",
+      "10mg",
+      "08:00–09:00",
+      20,
+      "en",
+    );
+    expect(result.title).toBe("🟡 Due soon: Ramipril");
+    expect(result.message).toContain("20 min left.");
+    expect(result.message).toContain("<b>Ramipril</b>");
+  });
+
+  it("falls back to default locale (en) for unknown / missing locale", () => {
+    const result = getPhaseMessage(
+      "ORANGE",
+      "Aspirin",
+      "100mg",
+      "12:00–13:00",
+      -90,
+      null,
+    );
+    expect(result.title).toBe("🟠 Overdue: Aspirin");
+    expect(result.message).toContain("Overdue by 90 min.");
+  });
+
+  it("RED phase template suppresses the per-message minutes count", () => {
+    const result = getPhaseMessage(
+      "RED",
+      "Aspirin",
+      "100mg",
+      "12:00–13:00",
+      -300,
+      "en",
+    );
+    expect(result.message).toContain("Marked as missed.");
+    expect(result.message).not.toContain("300");
+  });
+});
+
+describe("getPhaseKeyboard — localised", () => {
+  it("returns German labels for de locale", () => {
+    const kb = getPhaseKeyboard("YELLOW", "med-1", "de");
+    const flat = kb.inline_keyboard.flat();
+    expect(flat.find((b) => b.callback_data === "taken:med-1")?.text).toBe(
+      "Genommen",
+    );
+    expect(flat.find((b) => b.callback_data === "snooze:med-1:60")?.text).toBe(
+      "🕐 1h",
+    );
+    expect(flat.find((b) => b.callback_data === "skip:med-1")?.text).toBe(
+      "⏭ Überspringen",
+    );
+  });
+
+  it("returns English labels for en locale", () => {
+    const kb = getPhaseKeyboard("YELLOW", "med-1", "en");
+    const flat = kb.inline_keyboard.flat();
+    expect(flat.find((b) => b.callback_data === "taken:med-1")?.text).toBe(
+      "Taken",
+    );
+    expect(flat.find((b) => b.callback_data === "skip:med-1")?.text).toBe(
+      "⏭ Skip",
+    );
+  });
+
+  it("RED phase has Confirm button localised", () => {
+    expect(
+      getPhaseKeyboard("RED", "med-1", "en").inline_keyboard[0].find(
+        (b) => b.callback_data === "ack:med-1",
+      )?.text,
+    ).toBe("✓ Confirm");
+    expect(
+      getPhaseKeyboard("RED", "med-1", "de").inline_keyboard[0].find(
+        (b) => b.callback_data === "ack:med-1",
+      )?.text,
+    ).toBe("✓ Bestätigen");
+  });
+
+  it("callback_data values are NEVER translated (stable contract)", () => {
+    for (const locale of ["de", "en", null, "fr"] as const) {
+      const kb = getPhaseKeyboard("YELLOW", "med-x", locale);
+      const cb = kb.inline_keyboard.flat().map((b) => b.callback_data);
+      expect(cb).toContain("taken:med-x");
+      expect(cb).toContain("snooze:med-x:60");
+      expect(cb).toContain("snooze:med-x:180");
+      expect(cb).toContain("skip:med-x");
+    }
+  });
+});

src/lib/jobs/reminder-phases.ts

@@ -4,6 +4,9 @@
  * current time relative to the schedule window end.
  */
 
+import { defaultLocale, type Locale } from "@/lib/i18n/config";
+import { getServerTranslator } from "@/lib/i18n/server-translator";
+
 export type ReminderPhase = "GREEN" | "YELLOW" | "ORANGE" | "RED";
 export type PhaseMode = "MINUTES" | "PERCENT";
 
@@ -115,8 +118,18 @@ export function determinePhase(
   return null; // Not in any phase yet
 }
 
+function resolveLocale(locale: Locale | string | null | undefined): Locale {
+  return locale === "en" || locale === "de" ? locale : defaultLocale;
+}
+
 /**
- * Get the message template for a phase.
+ * Get the message template for a phase, localised to the recipient
+ * user. Strings live in `messages/{de,en}.json` under
+ * `medicationReminders.phase*`. The reminder worker passes the user's
+ * stored locale; absent / unknown locales fall back to the app default.
+ *
+ * v1.4 marathon — closes the v3 audit "Locale-Mixing" CRIT finding
+ * (German-only Telegram / Web Push templates regardless of user locale).
  */
 export function getPhaseMessage(
   phase: ReminderPhase,
@@ -124,47 +137,79 @@ export function getPhaseMessage(
   doseInfo: string,
   timeWindow: string,
   minutesToEnd: number,
+  locale: Locale | string | null | undefined,
 ): { title: string; message: string } {
-  const minutesPastEnd = -minutesToEnd;
+  const t = getServerTranslator(resolveLocale(locale)).t;
   const absMinutes = Math.abs(minutesToEnd);
+  const minutesPastEnd = Math.max(0, -minutesToEnd);
+
+  const params = (extra: Record<string, string | number>) => ({
+    medName,
+    doseInfo,
+    timeWindow,
+    ...extra,
+  });
 
   switch (phase) {
     case "GREEN":
       return {
-        title: `🟢 Erinnerung: ${medName}`,
-        message: `🟢 Erinnerung:\n<b>${medName}</b> (${doseInfo}, ${timeWindow})\nZeitfenster endet in ${absMinutes} Min.`,
+        title: t("medicationReminders.phaseGreenTitle", { medName }),
+        message: t(
+          "medicationReminders.phaseGreenMessage",
+          params({ minutes: absMinutes }),
+        ),
       };
     case "YELLOW":
       return {
-        title: `🟡 Bald fällig: ${medName}`,
-        message: `🟡 Bald fällig:\n<b>${medName}</b> (${doseInfo}, ${timeWindow})\nNoch ${absMinutes} Min. Zeit.`,
+        title: t("medicationReminders.phaseYellowTitle", { medName }),
+        message: t(
+          "medicationReminders.phaseYellowMessage",
+          params({ minutes: absMinutes }),
+        ),
       };
     case "ORANGE":
       return {
-        title: `🟠 Überfällig: ${medName}`,
-        message: `🟠 Überfällig:\n<b>${medName}</b> (${doseInfo}, ${timeWindow})\nSeit ${minutesPastEnd} Min. überfällig.`,
+        title: t("medicationReminders.phaseOrangeTitle", { medName }),
+        message: t(
+          "medicationReminders.phaseOrangeMessage",
+          params({ minutes: minutesPastEnd }),
+        ),
       };
     case "RED":
       return {
-        title: `🔴 Verpasst: ${medName}`,
-        message: `🔴 Verpasst:\n<b>${medName}</b> (${doseInfo}, ${timeWindow})\nAls verpasst markiert.`,
+        title: t("medicationReminders.phaseRedTitle", { medName }),
+        message: t(
+          "medicationReminders.phaseRedMessage",
+          params({ minutes: 0 }),
+        ),
       };
   }
 }
 
 /**
- * Get the inline keyboard for a phase.
+ * Get the inline keyboard for a phase. Button labels follow the user's
+ * locale; callback_data values are stable English identifiers and must
+ * NOT be translated (the bot dispatcher matches on them).
  */
 export function getPhaseKeyboard(
   phase: ReminderPhase,
   medicationId: string,
+  locale: Locale | string | null | undefined,
 ): { inline_keyboard: { text: string; callback_data: string }[][] } {
+  const t = getServerTranslator(resolveLocale(locale)).t;
+
   if (phase === "RED") {
     return {
       inline_keyboard: [
         [
-          { text: "Genommen", callback_data: `taken:${medicationId}` },
-          { text: "✓ Bestätigen", callback_data: `ack:${medicationId}` },
+          {
+            text: t("medicationReminders.buttonTaken"),
+            callback_data: `taken:${medicationId}`,
+          },
+          {
+            text: t("medicationReminders.buttonConfirm"),
+            callback_data: `ack:${medicationId}`,
+          },
         ],
       ],
     };
@@ -172,11 +217,25 @@ export function getPhaseKeyboard(
 
   return {
     inline_keyboard: [
-      [{ text: "Genommen", callback_data: `taken:${medicationId}` }],
       [
-        { text: "🕐 1h", callback_data: `snooze:${medicationId}:60` },
-        { text: "🕐 3h", callback_data: `snooze:${medicationId}:180` },
-        { text: "⏭ Überspringen", callback_data: `skip:${medicationId}` },
+        {
+          text: t("medicationReminders.buttonTaken"),
+          callback_data: `taken:${medicationId}`,
+        },
+      ],
+      [
+        {
+          text: t("medicationReminders.buttonSnoozeOneHour"),
+          callback_data: `snooze:${medicationId}:60`,
+        },
+        {
+          text: t("medicationReminders.buttonSnoozeThreeHours"),
+          callback_data: `snooze:${medicationId}:180`,
+        },
+        {
+          text: t("medicationReminders.buttonSkip"),
+          callback_data: `skip:${medicationId}`,
+        },
       ],
     ],
   };

src/lib/validations/__tests__/measurement.test.ts

@@ -27,18 +27,18 @@ describe("measurement validation", () => {
 
   describe("validateMeasurementRange", () => {
     it("rejects values below the plausible minimum", () => {
-      expect(validateMeasurementRange("WEIGHT", 0.5)).toMatch(/zwischen/);
-      expect(validateMeasurementRange("BONE_MASS", 0.1)).toMatch(/zwischen/);
+      expect(validateMeasurementRange("WEIGHT", 0.5)).toMatch(/between/i);
+      expect(validateMeasurementRange("BONE_MASS", 0.1)).toMatch(/between/i);
       expect(validateMeasurementRange("TOTAL_BODY_WATER", 1)).toMatch(
-        /zwischen/,
+        /between/i,
       );
     });
 
     it("rejects values above the plausible maximum", () => {
-      expect(validateMeasurementRange("WEIGHT", 600)).toMatch(/zwischen/);
-      expect(validateMeasurementRange("BONE_MASS", 12)).toMatch(/zwischen/);
+      expect(validateMeasurementRange("WEIGHT", 600)).toMatch(/between/i);
+      expect(validateMeasurementRange("BONE_MASS", 12)).toMatch(/between/i);
       expect(validateMeasurementRange("TOTAL_BODY_WATER", 200)).toMatch(
-        /zwischen/,
+        /between/i,
       );
     });
 

src/lib/validations/admin.ts

@@ -16,7 +16,7 @@ export const adminSettingsSchema = z
       .string()
       .refine((v) => !v.trim() || /^mailto:.+@.+$/.test(v.trim()), {
         message:
-          "Web Push Subject muss im Format mailto:adresse@example.com sein",
+          "webPushVapidSubject must be in mailto:address@example.com format",
       })
       .optional(),
     webPushVapidPrivateKey: z.string().optional(),
@@ -36,7 +36,7 @@ export const adminSettingsSchema = z
             return false;
           }
         },
-        { message: "Umami Script-URL ist ungültig" },
+        { message: "Umami script URL is invalid" },
       )
       .optional(),
     umamiWebsiteId: z.string().optional(),
@@ -54,7 +54,7 @@ export const adminSettingsSchema = z
             return false;
           }
         },
-        { message: "Glitchtip DSN ist ungültig" },
+        { message: "Glitchtip DSN is invalid" },
       )
       .optional(),
     glitchtipEnvironment: z.string().optional(),
@@ -66,7 +66,7 @@ export const adminSettingsSchema = z
           if (!trimmed) return true;
           return /^[A-Za-z0-9_.-]+\/[A-Za-z0-9_.-]+$/.test(trimmed);
         },
-        { message: "GitHub-Repository muss im Format owner/repo sein" },
+        { message: "GitHub repository must be in owner/repo format" },
       )
       .optional(),
     bugReportToken: z.string().optional(),

src/lib/validations/measurement.ts

@@ -66,7 +66,7 @@ export function validateMeasurementRange(
 ): string | null {
   const range = VALUE_RANGES[type];
   if (range && (value < range.min || value > range.max)) {
-    return `Wert muss zwischen ${range.min} und ${range.max} liegen`;
+    return `Value must be between ${range.min} and ${range.max}`;
   }
   return null;
 }
@@ -104,7 +104,7 @@ export const updateMeasurementSchema = z.object({
     .optional(),
   notes: z
     .string()
-    .max(25, "Kommentar darf maximal 25 Zeichen haben")
+    .max(25, "Note cannot exceed 25 characters")
     .nullable()
     .optional(),
 });