From ce4bca827248ad5d8b03321b0573badf64eaa7a3 Mon Sep 17 00:00:00 2001
From: MaysWind <i@mayswind.net>
Date: Sun, 8 Jun 2025 02:10:11 +0800
Subject: [PATCH] code refactor

---
 jest.config.ts                                |  50 ++--
 package.json                                  |   2 +-
 pkg/core/fiscalyear.go                        |  52 +++--
 pkg/core/fiscalyear_test.go                   |   3 +-
 .../base/FiscalYearStartSelectionBase.ts      | 125 +++++-----
 .../desktop/FiscalYearStartSelect.vue         |  64 +++---
 .../mobile/FiscalYearStartSelectionSheet.vue  |  69 +++---
 src/core/fiscalyear.ts                        | 216 +++++-------------
 src/lib/__tests__/fiscal_year.ts              |  88 ++++---
 src/lib/datetime.ts                           | 101 ++++----
 src/locales/helpers.ts                        |  44 ++--
 src/views/mobile/users/UserProfilePage.vue    |   7 +-
 tsconfig.jest.json                            |   7 +
 tsconfig.json                                 |   3 +-
 14 files changed, 364 insertions(+), 467 deletions(-)
 create mode 100644 tsconfig.jest.json

diff --git a/jest.config.ts b/jest.config.ts
index b1c97e05..08b9a939 100644
--- a/jest.config.ts
+++ b/jest.config.ts
@@ -1,37 +1,21 @@
-/**
- * For a detailed explanation regarding each configuration property, visit:
- * https://jestjs.io/docs/configuration
- */
+import { type JestConfigWithTsJest, createDefaultEsmPreset } from 'ts-jest';
 
-import type { Config } from 'jest';
-
-const config: Config = {
-
-  // Automatically clear mock calls, instances, contexts and results before every test
-  clearMocks: true,
-
-  // Indicates whether the coverage information should be collected while executing the test
-  collectCoverage: false,
-
-  // A map from regular expressions to module names or to arrays of module names that allow to stub out resources with a single module
-  moduleNameMapper: {
-    "^@/(.*)$": "<rootDir>/src/$1"
-  },
-
-  // The test environment that will be used for testing
-  testEnvironment: "node",
-
-  // The glob patterns Jest uses to detect test files
-  testMatch: [
-    "**/__tests__/**/*.[jt]s?(x)",
-    "!**/__tests__/*_gen.[jt]s?(x)"
-  ],
-
-  // A map from regular expressions to paths to transformers
-  transform: {
-    '^.+\\.m?tsx?$': ['ts-jest', { useESM: true, isolatedModules: true }],
-  },
+const presetConfig = createDefaultEsmPreset({
+    tsconfig: '<rootDir>/tsconfig.jest.json'
+});
 
+const config: JestConfigWithTsJest = {
+    ...presetConfig,
+    clearMocks: true,
+    collectCoverage: false,
+    moduleNameMapper: {
+        "^@/(.*)$": "<rootDir>/src/$1"
+    },
+    testEnvironment: "node",
+    testMatch: [
+        "**/__tests__/**/*.[jt]s?(x)",
+        "!**/__tests__/*_gen.[jt]s?(x)"
+    ]
 };
 
-module.exports = config;
+export default config;
diff --git a/package.json b/package.json
index b78b4e5f..73759060 100644
--- a/package.json
+++ b/package.json
@@ -16,7 +16,7 @@
     "build": "cross-env NODE_ENV=production vite build",
     "serve:dist": "vite preview",
     "lint": "tsc --noEmit && eslint . --fix",
-    "test": "jest"
+    "test": "cross-env TS_NODE_PROJECT=\"./tsconfig.jest.json\" jest"
   },
   "dependencies": {
     "@mdi/js": "^7.4.47",
diff --git a/pkg/core/fiscalyear.go b/pkg/core/fiscalyear.go
index bcbfa390..8c06264e 100644
--- a/pkg/core/fiscalyear.go
+++ b/pkg/core/fiscalyear.go
@@ -17,11 +17,25 @@ const (
 	FISCAL_YEAR_START_INVALID FiscalYearStart = 0xFFFF // Invalid
 )
 
+var MONTH_MAX_DAYS = []uint8{
+	uint8(31), // January
+	uint8(28), // February (Disallow fiscal year start on leap day)
+	uint8(31), // March
+	uint8(30), // April
+	uint8(31), // May
+	uint8(30), // June
+	uint8(31), // July
+	uint8(31), // August
+	uint8(30), // September
+	uint8(31), // October
+	uint8(30), // November
+	uint8(31), // December
+}
+
 // NewFiscalYearStart creates a new FiscalYearStart from month and day values
 func NewFiscalYearStart(month uint8, day uint8) (FiscalYearStart, error) {
-	month, day, err := validateMonthDay(month, day)
-	if err != nil {
-		return 0, err
+	if !isValidMonthDay(month, day) {
+		return 0, errs.ErrFormatInvalid
 	}
 
 	return FiscalYearStart(uint16(month)<<8 | uint16(day)), nil
@@ -37,39 +51,27 @@ func (f FiscalYearStart) GetMonthDay() (uint8, uint8, error) {
 	month := uint8(f >> 8)
 	day := uint8(f & 0xFF)
 
-	return validateMonthDay(month, day)
+	if !isValidMonthDay(month, day) {
+		return 0, 0, errs.ErrFormatInvalid
+	}
+
+	return month, day, nil
 }
 
 // String returns a string representation of FiscalYearStart in MM/DD format
 func (f FiscalYearStart) String() string {
 	month, day, err := f.GetMonthDay()
+
 	if err != nil {
 		return "Invalid"
 	}
+
 	return fmt.Sprintf("%02d-%02d", month, day)
 }
 
-// validateMonthDay validates a month and day and returns them if valid
-func validateMonthDay(month uint8, day uint8) (uint8, uint8, error) {
-	if month < 1 || month > 12 || day < 1 {
-		return 0, 0, errs.ErrFormatInvalid
-	}
-
-	maxDays := uint8(31)
-	switch month {
-	case 1, 3, 5, 7, 8, 10, 12: // January, March, May, July, August, October, December
-		maxDays = 31
-	case 4, 6, 9, 11: // April, June, September, November
-		maxDays = 30
-	case 2: // February
-		maxDays = 28 // Disallow fiscal year start on leap day
-	}
-
-	if day > maxDays {
-		return 0, 0, errs.ErrFormatInvalid
-	}
-
-	return month, day, nil
+// isValidMonthDay returns whether the specified month and day is valid
+func isValidMonthDay(month uint8, day uint8) bool {
+	return uint8(1) <= month && month <= uint8(12) && uint8(1) <= day && day <= MONTH_MAX_DAYS[int(month)-1]
 }
 
 // FiscalYearFormat represents the fiscal year format as a uint8
diff --git a/pkg/core/fiscalyear_test.go b/pkg/core/fiscalyear_test.go
index 9cffd1b3..2dfe1df7 100644
--- a/pkg/core/fiscalyear_test.go
+++ b/pkg/core/fiscalyear_test.go
@@ -3,8 +3,9 @@ package core
 import (
 	"testing"
 
-	"github.com/mayswind/ezbookkeeping/pkg/errs"
 	"github.com/stretchr/testify/assert"
+
+	"github.com/mayswind/ezbookkeeping/pkg/errs"
 )
 
 func TestNewFiscalYearStart_ValidMonthDay(t *testing.T) {
diff --git a/src/components/base/FiscalYearStartSelectionBase.ts b/src/components/base/FiscalYearStartSelectionBase.ts
index 4a4ba210..b221fd95 100644
--- a/src/components/base/FiscalYearStartSelectionBase.ts
+++ b/src/components/base/FiscalYearStartSelectionBase.ts
@@ -1,88 +1,95 @@
-import { computed } from 'vue';
+import { ref, computed } from 'vue';
 
 import { FiscalYearStart } from '@/core/fiscalyear.ts';
-
-import { useUserStore } from '@/stores/user.ts';
+import { arrangeArrayWithNewStartIndex } from '@/lib/common.ts';
 
 import { useI18n } from '@/locales/helpers.ts';
 
-import { arrangeArrayWithNewStartIndex } from '@/lib/common';
+import { useUserStore } from '@/stores/user.ts';
 
-export interface FiscalYearStartSelectionBaseProps {
+export interface CommonFiscalYearStartSelectionProps {
     modelValue?: number;
+    disabled?: boolean;
+    readonly?: boolean;
+    label?: string;
 }
 
-export interface FiscalYearStartSelectionBaseEmits {
+export interface CommonFiscalYearStartSelectionEmits {
     (e: 'update:modelValue', value: number): void;
 }
 
-export function useFiscalYearStartSelectionBase(props: FiscalYearStartSelectionBaseProps, emit: FiscalYearStartSelectionBaseEmits) {
-    const { getAllMinWeekdayNames, formatMonthDayToLongDay, getCurrentFiscalYearStartFormatted } = useI18n();
+function getFiscalYearStartFromProps(props: CommonFiscalYearStartSelectionProps): number {
+    if (!props.modelValue) {
+        return FiscalYearStart.Default.value;
+    }
 
-    const dayNames = computed<string[]>(() => arrangeArrayWithNewStartIndex(getAllMinWeekdayNames(), firstDayOfWeek.value));
+    const fiscalYearStart = FiscalYearStart.valueOf(props.modelValue);
 
-    const displayName = computed<string>(() => {
-        const fy = FiscalYearStart.fromNumber(selectedFiscalYearStart.value);
+    if (!fiscalYearStart) {
+        return FiscalYearStart.Default.value;
+    }
 
-        if ( fy ) {
-            return formatMonthDayToLongDay(fy.toMonthDashDayString())
-        }
+    return fiscalYearStart.value;
+}
 
-        return formatMonthDayToLongDay(FiscalYearStart.strictFromNumber(userStore.currentUserFiscalYearStart).toMonthDashDayString());
-
-    });
-
-    const disabledDates = (date: Date) => {
-        // Disable February 29 (leap day)
-        return date.getMonth() === 1 && date.getDate() === 29; 
-    };
-
-    const firstDayOfWeek = computed<number>(() => userStore.currentUserFirstDayOfWeek);
-
-    const selectedFiscalYearStart = computed<number>(() => {
-        return props.modelValue !== undefined ? props.modelValue : userStore.currentUserFiscalYearStart;
-    });
+export function useFiscalYearStartSelectionBase(props: CommonFiscalYearStartSelectionProps) {
+    const {
+        getAllMinWeekdayNames,
+        formatMonthDayToLongDay
+    } = useI18n();
 
     const userStore = useUserStore();
 
-    function selectedDisplayName(dateString: string): string {
-        const fy = FiscalYearStart.fromMonthDashDayString(dateString);
-        if ( fy ) {
-            return formatMonthDayToLongDay(fy.toMonthDashDayString());
+    const disabledDates = (date: Date) => {
+        // Disable February 29 (leap day)
+        return date.getMonth() === 1 && date.getDate() === 29;
+    };
+
+    const selectedFiscalYearStart = ref<number>(getFiscalYearStartFromProps(props));
+
+    const selectedFiscalYearStartValue = computed<string>({
+        get: () => {
+            const fiscalYearStart = FiscalYearStart.valueOf(selectedFiscalYearStart.value);
+
+            if (fiscalYearStart) {
+                return fiscalYearStart.toMonthDashDayString();
+            } else {
+                return FiscalYearStart.Default.toMonthDashDayString();
+            }
+        },
+        set: (value: string) => {
+            const fiscalYearStart = FiscalYearStart.parse(value);
+
+            if (fiscalYearStart) {
+                selectedFiscalYearStart.value = fiscalYearStart.value;
+            } else {
+                selectedFiscalYearStart.value = FiscalYearStart.Default.value;
+            }
         }
-        return displayName.value;
-    }
+    });
 
-    function getModelValueToDateString(): string {
-        const input = selectedFiscalYearStart.value;
-        
-        const fy = FiscalYearStart.fromNumber(input);
+    const displayFiscalYearStartDate = computed<string>(() => {
+        let fiscalYearStart = FiscalYearStart.valueOf(selectedFiscalYearStart.value);
 
-        if ( fy ) {
-            return fy.toMonthDashDayString();
+        if (!fiscalYearStart) {
+            fiscalYearStart = FiscalYearStart.Default;
         }
 
-        return getCurrentFiscalYearStartFormatted();
-    }
+        return formatMonthDayToLongDay(fiscalYearStart.toMonthDashDayString());
+    });
+
+    const firstDayOfWeek = computed<number>(() => userStore.currentUserFirstDayOfWeek);
+    const dayNames = computed<string[]>(() => arrangeArrayWithNewStartIndex(getAllMinWeekdayNames(), firstDayOfWeek.value));
 
-    function getDateStringToModelValue(input: string): number {
-        const fyString = FiscalYearStart.fromMonthDashDayString(input);
-        if (fyString) {
-            return fyString.value;
-        }
-        return userStore.currentUserFiscalYearStart;
-    }
-    
     return {
-        // functions
-        getDateStringToModelValue,
-        getModelValueToDateString,
-        selectedDisplayName,
-        // computed states
-        dayNames,
-        displayName,
+        // constants
         disabledDates,
-        firstDayOfWeek,
+        // states,
         selectedFiscalYearStart,
-    }
+        // computed states
+        selectedFiscalYearStartValue,
+        displayFiscalYearStartDate,
+        firstDayOfWeek,
+        dayNames
+    };
 }
diff --git a/src/components/desktop/FiscalYearStartSelect.vue b/src/components/desktop/FiscalYearStartSelect.vue
index b057e0a0..88814875 100644
--- a/src/components/desktop/FiscalYearStartSelect.vue
+++ b/src/components/desktop/FiscalYearStartSelect.vue
@@ -3,18 +3,16 @@
         persistent-placeholder
         :readonly="readonly"
         :disabled="disabled"
-        :clearable="modelValue ? clearable : false"
         :label="label"
         :menu-props="{ contentClass: 'fiscal-year-start-select-menu' }"
-        v-model="selectedDate"
+        v-model="selectedFiscalYearStartValue"
     >
         <template #selection>
-            <span class="text-truncate cursor-pointer">{{ displayName }}</span>
+            <span class="text-truncate cursor-pointer">{{ displayFiscalYearStartDate }}</span>
         </template>
 
         <template #no-data>
-            <vue-date-picker inline vertical auto-apply hide-offset-dates disable-year-select
-                             ref="datepicker"
+            <vue-date-picker inline auto-apply hide-offset-dates disable-year-select
                              month-name-format="long"
                              model-type="MM-dd"
                              :clearable="false"
@@ -23,8 +21,7 @@
                              :week-start="firstDayOfWeek"
                              :day-names="dayNames"
                              :disabled-dates="disabledDates"
-                             :start-date="selectedDate"
-                             v-model="selectedDate"
+                             v-model="selectedFiscalYearStartValue"
                              >
                 <template #month="{ text }">
                     {{ getMonthShortName(text) }}
@@ -38,51 +35,46 @@
 </template>
 
 <script setup lang="ts">
-import { computed } from 'vue';
+import { computed, watch } from 'vue';
 import { useTheme } from 'vuetify';
-import { useUserStore } from '@/stores/user.ts';
-import { ThemeType } from '@/core/theme.ts';
-import { arrangeArrayWithNewStartIndex } from '@/lib/common.ts';
-import {
-    type FiscalYearStartSelectionBaseProps,
-    type FiscalYearStartSelectionBaseEmits,
-    useFiscalYearStartSelectionBase
-} from '@/components/base/FiscalYearStartSelectionBase.ts';
+
 import { useI18n } from '@/locales/helpers.ts';
 
-interface FiscalYearStartSelectProps extends FiscalYearStartSelectionBaseProps {
-    disabled?: boolean;
-    readonly?: boolean;
-    clearable?: boolean;
-    label?: string;
-}
+import {
+    type CommonFiscalYearStartSelectionProps,
+    type CommonFiscalYearStartSelectionEmits,
+    useFiscalYearStartSelectionBase
+} from '@/components/base/FiscalYearStartSelectionBase.ts';
 
-const props = defineProps<FiscalYearStartSelectProps>();
-const emit = defineEmits<FiscalYearStartSelectionBaseEmits>();
+import { ThemeType } from '@/core/theme.ts';
+
+const props = defineProps<CommonFiscalYearStartSelectionProps>();
+const emit = defineEmits<CommonFiscalYearStartSelectionEmits>();
 
 const { getMonthShortName } = useI18n();
+
 const theme = useTheme();
 
 const isDarkMode = computed<boolean>(() => theme.global.name.value === ThemeType.Dark);
 
-// Get all base functionality
 const {
-    dayNames,
-    displayName,
     disabledDates,
+    selectedFiscalYearStart,
+    selectedFiscalYearStartValue,
+    displayFiscalYearStartDate,
     firstDayOfWeek,
-    getModelValueToDateString,
-    getDateStringToModelValue,
-} = useFiscalYearStartSelectionBase(props, emit);
+    dayNames
+} = useFiscalYearStartSelectionBase(props);
 
-const selectedDate = computed<string>({
-    get: () => {
-        return getModelValueToDateString();
-    },
-    set: (value: string) => {
-        emit('update:modelValue', getDateStringToModelValue(value));
+watch(() => props.modelValue, (newValue) => {
+    if (newValue) {
+        selectedFiscalYearStart.value = newValue;
     }
 });
+
+watch(selectedFiscalYearStart, (newValue) => {
+    emit('update:modelValue', newValue);
+});
 </script>
 
 <style>
diff --git a/src/components/mobile/FiscalYearStartSelectionSheet.vue b/src/components/mobile/FiscalYearStartSelectionSheet.vue
index 277af410..5b5fc488 100644
--- a/src/components/mobile/FiscalYearStartSelectionSheet.vue
+++ b/src/components/mobile/FiscalYearStartSelectionSheet.vue
@@ -4,7 +4,7 @@
         <f7-toolbar>
             <div class="swipe-handler"></div>
             <div class="left">
-                <f7-link :text="tt('Clear')" @click="clear"></f7-link>
+                <f7-link :text="tt('Reset')" @click="reset"></f7-link>
             </div>
             <div class="right">
                 <f7-link :text="tt('Done')" @click="confirm"></f7-link>
@@ -17,14 +17,13 @@
                                  model-type="MM-dd"
                                  six-weeks="center"
                                  class="justify-content-center"
+                                 :clearable="false"
                                  :enable-time-picker="false"
-                                 :clearable="true"
                                  :dark="isDarkMode"
                                  :week-start="firstDayOfWeek"
                                  :day-names="dayNames"
                                  :disabled-dates="disabledDates"
-                                 :start-date="selectedDate"
-                                 v-model="selectedDate">
+                                 v-model="selectedFiscalYearStartValue">
                     <template #month="{ text }">
                         {{ getMonthShortName(text) }}
                     </template>
@@ -38,71 +37,71 @@
 </template>
 
 <script setup lang="ts">
-import { computed, ref } from 'vue';
+import { computed } from 'vue';
 
 import { useI18n } from '@/locales/helpers.ts';
 
 import { useEnvironmentsStore } from '@/stores/environment.ts';
+import { useUserStore } from '@/stores/user.ts';
 
 import {
-    type FiscalYearStartSelectionBaseProps,
-    type FiscalYearStartSelectionBaseEmits,
+    type CommonFiscalYearStartSelectionProps,
+    type CommonFiscalYearStartSelectionEmits,
     useFiscalYearStartSelectionBase
 } from '@/components/base/FiscalYearStartSelectionBase.ts';
 
-interface FiscalYearStartSelectionSheetProps extends FiscalYearStartSelectionBaseProps {
+import { FiscalYearStart } from '@/core/fiscalyear.ts';
+
+interface MobileFiscalYearStartSelectionSheetProps extends CommonFiscalYearStartSelectionProps {
     clearable?: boolean;
-    disabled?: boolean;
-    label?: string;
-    readonly?: boolean;
     show: boolean;
     title?: string;
 }
 
-const props = defineProps<FiscalYearStartSelectionSheetProps>();
-
-interface FiscalYearStartSelectionSheetEmits extends FiscalYearStartSelectionBaseEmits {
+interface MobileFiscalYearStartSelectionSheetEmits extends CommonFiscalYearStartSelectionEmits {
     (e: 'update:show', value: boolean): void;
-    (e: 'update:title', value: string): void;
 }
 
-const emit = defineEmits<FiscalYearStartSelectionSheetEmits>();
+const props = defineProps<MobileFiscalYearStartSelectionSheetProps>();
+const emit = defineEmits<MobileFiscalYearStartSelectionSheetEmits>();
 
-const { tt, getMonthShortName, getCurrentFiscalYearStartFormatted } = useI18n();
+const { tt, getMonthShortName } = useI18n();
 
 const environmentsStore = useEnvironmentsStore();
+const userStore = useUserStore();
 
 const {
-    dayNames,
     disabledDates,
+    selectedFiscalYearStart,
+    selectedFiscalYearStartValue,
     firstDayOfWeek,
-    getDateStringToModelValue,
-    getModelValueToDateString,
-    selectedDisplayName,
-} = useFiscalYearStartSelectionBase(props, emit);
+    dayNames
+} = useFiscalYearStartSelectionBase(props);
 
 const isDarkMode = computed<boolean>(() => environmentsStore.framework7DarkMode || false);
 
-const selectedDate = ref<string>(getModelValueToDateString());
+function confirm(): void {
+    emit('update:modelValue', selectedFiscalYearStart.value);
+    emit('update:show', false);
+}
+
+function reset(): void {
+    selectedFiscalYearStart.value = userStore.currentUserFiscalYearStart;
+}
 
 function onSheetOpen(): void {
-    selectedDate.value = getModelValueToDateString();
+    if (props.modelValue) {
+        const fiscalYearStart = FiscalYearStart.valueOf(props.modelValue);
+
+        if (fiscalYearStart) {
+            selectedFiscalYearStart.value = fiscalYearStart.value;
+        }
+    }
 }
 
 function onSheetClosed(): void {
     emit('update:show', false);
 }
-
-function clear(): void {
-    selectedDate.value = getCurrentFiscalYearStartFormatted();
-}
-
-function confirm(): void {
-    emit('update:modelValue', getDateStringToModelValue(selectedDate.value));
-    emit('update:show', false);
-    emit('update:title', selectedDisplayName(selectedDate.value));
-}
-
 </script>
 
 <style>
diff --git a/src/core/fiscalyear.ts b/src/core/fiscalyear.ts
index 5940211f..05bdc6c0 100644
--- a/src/core/fiscalyear.ts
+++ b/src/core/fiscalyear.ts
@@ -1,197 +1,87 @@
-import type { TypeAndDisplayName } from '@/core/base.ts';
-import type { UnixTimeRange } from './datetime';
+import type { UnixTimeRange } from './datetime.ts';
 
 export class FiscalYearStart {
-    public static readonly Default = new FiscalYearStart(1, 1);
+    public static readonly JanuaryFirstDay = new FiscalYearStart(1, 1);
+    public static readonly Default = FiscalYearStart.JanuaryFirstDay;
+
+    private static readonly MONTH_MAX_DAYS: number[] = [
+        31, // January
+        28, // February (Disallow fiscal year start on leap day)
+        31, // March
+        30, // April
+        31, // May
+        30, // June
+        31, // July
+        31, // August
+        30, // September
+        31, // October
+        30, // November
+        31 // December
+    ];
 
-    public readonly day: number;
     public readonly month: number;
+    public readonly day: number;
     public readonly value: number;
 
     private constructor(month: number, day: number) {
-        const [validMonth, validDay] = validateMonthDay(month, day);
-        this.day = validDay;
-        this.month = validMonth;
-        this.value = (validMonth << 8) | validDay;
+        this.month = month;
+        this.day = day;
+        this.value = (month << 8) | day;
     }
 
-    public static of(month: number, day: number): FiscalYearStart {
+    public static of(month: number, day: number): FiscalYearStart | undefined {
+        if (!FiscalYearStart.isValidMonthDay(month, day)) {
+            return undefined;
+        }
+
         return new FiscalYearStart(month, day);
     }
 
-    public static valueOf(value: number): FiscalYearStart {
-        return FiscalYearStart.strictFromNumber(value);
-    }
-
-    public static valuesFromNumber(value: number): number[] {
-        return FiscalYearStart.strictFromNumber(value).values();
-    }
-
-    public values(): number[] {
-        return [
-            this.month,
-            this.day
-        ];
-    }
-
-    public static parse(valueString: string): FiscalYearStart | undefined {
-        return FiscalYearStart.strictFromMonthDashDayString(valueString);
-    }
-
-    public static isValidType(value: number): boolean {
-        if (value < 0x0101 || value > 0x0C1F) {
-            return false;
-        }
-        
-        const month = (value >> 8) & 0xFF;
-        const day = value & 0xFF;
-        
-        try {
-            validateMonthDay(month, day);
-            return true;
-        } catch (error) {
-            return false;
-        }
-    }
-
-    public isValid(): boolean {
-        try {
-            FiscalYearStart.validateMonthDay(this.month, this.day);
-            return true;
-        } catch (error) {
-            return false;
-        }
-    }
-
-    public isDefault(): boolean {
-        return this.month === 1 && this.day === 1;
-    }
-
-    public static validateMonthDay(month: number, day: number): [number, number] {
-        return validateMonthDay(month, day);
-    }
-
-    public static strictFromMonthDayValues(month: number, day: number): FiscalYearStart {
-        return FiscalYearStart.of(month, day);
-    }
-
     /**
      * Create a FiscalYearStart from a uint16 value (two bytes - month high, day low)
      * @param value uint16 value (month in high byte, day in low byte)
-     * @returns FiscalYearStart instance
+     * @returns FiscalYearStart instance or undefined if the value is out of range
      */
-    public static strictFromNumber(value: number): FiscalYearStart {
-        if (value < 0 || value > 0xFFFF) {
-            throw new Error('Invalid uint16 value');
+    public static valueOf(value: number): FiscalYearStart | undefined {
+        if (value < 0x0101 || value > 0x0C1F) {
+            return undefined;
         }
 
         const month = (value >> 8) & 0xFF;  // high byte
         const day = value & 0xFF;           // low byte
 
-        try {
-            const [validMonth, validDay] = validateMonthDay(month, day);
-            return FiscalYearStart.of(validMonth, validDay);
-        } catch (error) {
-            throw new Error('Invalid uint16 value');
-        }
+        return FiscalYearStart.of(month, day);
     }
 
     /**
      * Create a FiscalYearStart from a month/day string
-     * @param input MM-dd string (e.g. "04-01" = 1 April)
-     * @returns FiscalYearStart instance
+     * @param monthDay MM-dd string (e.g. "04-01" = 1 April)
+     * @returns FiscalYearStart instance or undefined if the monthDay is invalid
      */
-    public static strictFromMonthDashDayString(input: string): FiscalYearStart {
-        if (!input || !input.includes('-')) {
-            throw new Error('Invalid input string');
+    public static parse(monthDay: string): FiscalYearStart | undefined {
+        if (!monthDay || !monthDay.includes('-')) {
+            return undefined;
         }
 
-        const parts = input.split('-');
+        const parts = monthDay.split('-');
+
         if (parts.length !== 2) {
-            throw new Error('Invalid input string');
+            return undefined;
         }
 
         const month = parseInt(parts[0], 10);
         const day = parseInt(parts[1], 10);
 
-        if (isNaN(month) || isNaN(day)) {
-            throw new Error('Invalid input string');
-        }
-
-        try {
-            const [validMonth, validDay] = validateMonthDay(month, day);
-            return FiscalYearStart.of(validMonth, validDay);
-        } catch (error) {
-            throw new Error('Invalid input string');
-        }
-    }
-
-    public static fromMonthDashDayString(input: string): FiscalYearStart | null {
-        try {
-            return FiscalYearStart.strictFromMonthDashDayString(input);
-        } catch (error) {
-            return null;
-        }
-    }
-
-    public static fromNumber(value: number): FiscalYearStart | null {
-        try {
-            return FiscalYearStart.strictFromNumber(value);
-        } catch (error) {
-            return null;
-        }
-    }
-
-    public static fromMonthDayValues(month: number, day: number): FiscalYearStart | null {
-        try {
-            return FiscalYearStart.strictFromMonthDayValues(month, day);
-        } catch (error) {
-            return null;
-        }
+        return FiscalYearStart.of(month, day);
     }
 
     public toMonthDashDayString(): string {
         return `${this.month.toString().padStart(2, '0')}-${this.day.toString().padStart(2, '0')}`;
     }
 
-    public toMonthDayValues(): [string, string] {
-        return [
-            `${this.month.toString().padStart(2, '0')}`,
-            `${this.day.toString().padStart(2, '0')}`
-        ]
+    private static isValidMonthDay(month: number, day: number): boolean {
+        return 1 <= month && month <= 12 && 1 <= day && day <= FiscalYearStart.MONTH_MAX_DAYS[month - 1];
     }
-
-    public toString(): string {
-        return this.toMonthDashDayString();
-    }
-}
-
-function validateMonthDay(month: number, day: number): [number, number] {
-    if (month < 1 || month > 12 || day < 1) {
-        throw new Error('Invalid month or day');
-    }
-
-    let maxDays = 31;
-    switch (month) {
-        // January, March, May, July, August, October, December
-        case 1: case 3: case 5: case 7: case 8: case 10: case 12: 
-            maxDays = 31;
-            break;
-        // April, June, September, November
-        case 4: case 6: case 9: case 11: 
-            maxDays = 30;
-            break;
-        // February
-        case 2: 
-            maxDays = 28; // Disallow fiscal year start on leap day
-            break;
-    }
-
-    if (day > maxDays) {
-        throw new Error('Invalid day for given month');
-    }
-
-    return [month, day];
 }
 
 export class FiscalYearUnixTime implements UnixTimeRange {
@@ -212,7 +102,7 @@ export class FiscalYearUnixTime implements UnixTimeRange {
 
 export const LANGUAGE_DEFAULT_FISCAL_YEAR_FORMAT_VALUE: number = 0;
 
-export class FiscalYearFormat implements TypeAndDisplayName {
+export class FiscalYearFormat {
     private static readonly allInstances: FiscalYearFormat[] = [];
     private static readonly allInstancesByType: Record<number, FiscalYearFormat> = {};
     private static readonly allInstancesByTypeName: Record<string, FiscalYearFormat> = {};
@@ -226,19 +116,15 @@ export class FiscalYearFormat implements TypeAndDisplayName {
     public static readonly Default = FiscalYearFormat.EndYYYY;
 
     public readonly type: number;
-    public readonly displayName: string;
+    public readonly typeName: string;
 
-    private constructor(type: number, displayName: string) {
+    private constructor(type: number, typeName: string) {
         this.type = type;
-        this.displayName = displayName;
-        
+        this.typeName = typeName;
+
         FiscalYearFormat.allInstances.push(this);
         FiscalYearFormat.allInstancesByType[type] = this;
-        FiscalYearFormat.allInstancesByTypeName[displayName] = this;
-    }
-
-    public static all(): Record<string, FiscalYearFormat> {
-        return FiscalYearFormat.allInstancesByTypeName;
+        FiscalYearFormat.allInstancesByTypeName[typeName] = this;
     }
 
     public static values(): FiscalYearFormat[] {
@@ -249,7 +135,7 @@ export class FiscalYearFormat implements TypeAndDisplayName {
         return FiscalYearFormat.allInstancesByType[type];
     }
 
-    public static parse(displayName: string): FiscalYearFormat | undefined {
-        return FiscalYearFormat.allInstancesByTypeName[displayName];
+    public static parse(typeName: string): FiscalYearFormat | undefined {
+        return FiscalYearFormat.allInstancesByTypeName[typeName];
     }
 }
diff --git a/src/lib/__tests__/fiscal_year.ts b/src/lib/__tests__/fiscal_year.ts
index bfdaaeac..9189c6c1 100644
--- a/src/lib/__tests__/fiscal_year.ts
+++ b/src/lib/__tests__/fiscal_year.ts
@@ -1,30 +1,29 @@
 // Unit tests for fiscal year functions
-import moment from 'moment-timezone';
-import { describe, expect, test, beforeAll } from '@jest/globals';
 import fs from 'fs';
 import path from 'path';
+import { describe, expect, test, beforeAll } from '@jest/globals';
+import moment from 'moment-timezone';
 
 // Import all the fiscal year functions from the lib
+import { FiscalYearStart, FiscalYearUnixTime } from '@/core/fiscalyear.ts';
+
 import {
     getFiscalYearFromUnixTime,
     getFiscalYearStartUnixTime,
     getFiscalYearEndUnixTime,
     getFiscalYearTimeRangeFromUnixTime,
     getAllFiscalYearsStartAndEndUnixTimes,
-    getFiscalYearTimeRangeFromYear
+    getFiscalYearTimeRangeFromYear,
+    formatUnixTime
 } from '@/lib/datetime.ts';
 
-import { formatUnixTime } from '@/lib/datetime.ts';
-import { FiscalYearStart, FiscalYearUnixTime } from '@/core/fiscalyear.ts';
-
 // Set test environment timezone to UTC, since the test data constants are in UTC
 beforeAll(() => {
     moment.tz.setDefault('UTC');
 });
 
 // UTILITIES
-
-function importTestData(datasetName: string): any[] {
+function importTestData(datasetName: string): unknown[] {
     const data = JSON.parse(
         fs.readFileSync(path.join(__dirname, 'fiscal_year.data.json'), 'utf8')
     );
@@ -74,13 +73,13 @@ const TEST_FISCAL_YEAR_START_PRESETS: Record<string, FiscalYearStartConfig> = {
 // VALIDATE FISCAL YEAR START PRESETS
 describe('validateFiscalYearStart', () => {
     Object.values(TEST_FISCAL_YEAR_START_PRESETS).forEach((testFiscalYearStart) => {
-        test(`should return true if fiscal year start value (uint16) is valid: id: ${testFiscalYearStart.id}; value: 0x${testFiscalYearStart.value.toString(16)}`, () => {
-            expect(FiscalYearStart.isValidType(testFiscalYearStart.value)).toBe(true);
+        test(`should return fiscal year start object if fiscal year start value (uint16) is valid: id: ${testFiscalYearStart.id}; value: 0x${testFiscalYearStart.value.toString(16)}`, () => {
+            expect(FiscalYearStart.valueOf(testFiscalYearStart.value)).toBeDefined();
         });
 
         test(`returns same month-date string for valid fiscal year start value: id: ${testFiscalYearStart.id}; value: 0x${testFiscalYearStart.value.toString(16)}`, () => {
-            const fiscalYearStart = FiscalYearStart.strictFromNumber(testFiscalYearStart.value);
-            expect(fiscalYearStart.toString()).toStrictEqual(testFiscalYearStart.monthDateString);
+            const fiscalYearStart = FiscalYearStart.valueOf(testFiscalYearStart.value);
+            expect(fiscalYearStart?.toMonthDashDayString()).toStrictEqual(testFiscalYearStart.monthDateString);
         });
     });
 });
@@ -103,24 +102,20 @@ const TestCase_invalidFiscalYearValues = [
 
 describe('validateFiscalYearStartInvalidValues', () => {
     TestCase_invalidFiscalYearValues.forEach((testCase) => {
-        test(`should return false if fiscal year start value (uint16) is invalid: value: 0x${testCase.toString(16)}`, () => {
-            expect(FiscalYearStart.isValidType(testCase)).toBe(false);
+        test(`should return undefined if fiscal year start value (uint16) is invalid: value: 0x${testCase.toString(16)}`, () => {
+            expect(FiscalYearStart.valueOf(testCase)).not.toBeDefined();
         });
     });
 });
 
 // VALIDATE LEAP DAY FEBRUARY 29 IS NOT VALID
 describe('validateFiscalYearStartLeapDay', () => {
-    test(`should return false if fiscal year start value (uint16) for February 29 is invalid: value: 0x0229}`, () => {
-        expect(FiscalYearStart.isValidType(0x0229)).toBe(false);
+    test(`should return undefined if fiscal year start value (uint16) for February 29 is invalid: value: 0x0229}`, () => {
+        expect(FiscalYearStart.valueOf(0x021D)).not.toBeDefined();
     });
 
-    test(`should return error if fiscal year month-day string "02-29" is used to create fiscal year start object`, () => {
-        expect(() => FiscalYearStart.strictFromMonthDashDayString('02-29')).toThrow();
-    });
-
-    test(`should return error if integers "02" and "29" are used to create fiscal year start object`, () => {
-        expect(() => FiscalYearStart.validateMonthDay(2, 29)).toThrow();
+    test(`should return undefined if fiscal year month-day string "02-29" is used to create fiscal year start object`, () => {
+        expect(FiscalYearStart.parse('02-29')).not.toBeDefined();
     });
 });
 
@@ -133,8 +128,8 @@ type TestCase_getFiscalYearFromUnixTime = {
     };
 };
 
-let TEST_CASES_GET_FISCAL_YEAR_FROM_UNIX_TIME: TestCase_getFiscalYearFromUnixTime[];
-TEST_CASES_GET_FISCAL_YEAR_FROM_UNIX_TIME = importTestData('test_cases_getFiscalYearFromUnixTime') as TestCase_getFiscalYearFromUnixTime[];
+const TEST_CASES_GET_FISCAL_YEAR_FROM_UNIX_TIME: TestCase_getFiscalYearFromUnixTime[] =
+    importTestData('test_cases_getFiscalYearFromUnixTime') as TestCase_getFiscalYearFromUnixTime[];
 
 describe('getFiscalYearFromUnixTime', () => {
     Object.values(TEST_FISCAL_YEAR_START_PRESETS).forEach((testFiscalYearStart) => {
@@ -161,8 +156,8 @@ type TestCase_getFiscalYearStartUnixTime = {
     };
 }
 
-let TEST_CASES_GET_FISCAL_YEAR_START_UNIX_TIME: TestCase_getFiscalYearStartUnixTime[];
-TEST_CASES_GET_FISCAL_YEAR_START_UNIX_TIME = importTestData('test_cases_getFiscalYearStartUnixTime') as TestCase_getFiscalYearStartUnixTime[];
+const TEST_CASES_GET_FISCAL_YEAR_START_UNIX_TIME: TestCase_getFiscalYearStartUnixTime[] =
+    importTestData('test_cases_getFiscalYearStartUnixTime') as TestCase_getFiscalYearStartUnixTime[];
 
 describe('getFiscalYearStartUnixTime', () => {
     Object.values(TEST_FISCAL_YEAR_START_PRESETS).forEach((testFiscalYearStart) => {
@@ -172,7 +167,7 @@ describe('getFiscalYearStartUnixTime', () => {
                 const startUnixTime = getFiscalYearStartUnixTime(testCaseUnixTime, testFiscalYearStart.value);
                 const expected = testCase.expected[testFiscalYearStart.id];
                 const unixTimeISO = formatUnixTimeISO(startUnixTime);
-                
+
                 expect({ unixTime: startUnixTime, ISO: unixTimeISO }).toStrictEqual({ unixTime: expected.unixTime, ISO: expected.unixTimeISO });
             });
         });
@@ -191,8 +186,8 @@ type TestCase_getFiscalYearEndUnixTime = {
     };
 }
 
-let TEST_CASES_GET_FISCAL_YEAR_END_UNIX_TIME: TestCase_getFiscalYearEndUnixTime[];
-TEST_CASES_GET_FISCAL_YEAR_END_UNIX_TIME = importTestData('test_cases_getFiscalYearEndUnixTime') as TestCase_getFiscalYearEndUnixTime[];
+const TEST_CASES_GET_FISCAL_YEAR_END_UNIX_TIME: TestCase_getFiscalYearEndUnixTime[] =
+    importTestData('test_cases_getFiscalYearEndUnixTime') as TestCase_getFiscalYearEndUnixTime[];
 
 describe('getFiscalYearEndUnixTime', () => {
     Object.values(TEST_FISCAL_YEAR_START_PRESETS).forEach((testFiscalYearStart) => {
@@ -202,9 +197,9 @@ describe('getFiscalYearEndUnixTime', () => {
                 const endUnixTime = getFiscalYearEndUnixTime(testCaseUnixTime, testFiscalYearStart.value);
                 const expected = testCase.expected[testFiscalYearStart.id];
                 const unixTimeISO = formatUnixTimeISO(endUnixTime);
-                
+
                 expect({ unixTime: endUnixTime, ISO: unixTimeISO }).toStrictEqual({ unixTime: expected.unixTime, ISO: expected.unixTimeISO });
-            
+
             });
         });
     });
@@ -218,8 +213,8 @@ type TestCase_getFiscalYearTimeRangeFromUnixTime = {
     }
 }
 
-let TEST_CASES_GET_FISCAL_YEAR_UNIX_TIME_RANGE: TestCase_getFiscalYearTimeRangeFromUnixTime[];
-TEST_CASES_GET_FISCAL_YEAR_UNIX_TIME_RANGE = importTestData('test_cases_getFiscalYearTimeRangeFromUnixTime') as TestCase_getFiscalYearTimeRangeFromUnixTime[];
+const TEST_CASES_GET_FISCAL_YEAR_UNIX_TIME_RANGE: TestCase_getFiscalYearTimeRangeFromUnixTime[] =
+    importTestData('test_cases_getFiscalYearTimeRangeFromUnixTime') as TestCase_getFiscalYearTimeRangeFromUnixTime[];
 
 describe('getFiscalYearTimeRangeFromUnixTime', () => {
     Object.values(TEST_FISCAL_YEAR_START_PRESETS).forEach((testFiscalYearStart) => {
@@ -242,29 +237,31 @@ type TestCase_getAllFiscalYearsStartAndEndUnixTimes = {
     expected: FiscalYearUnixTime[]
 }
 
-let TEST_CASES_GET_ALL_FISCAL_YEARS_START_AND_END_UNIX_TIMES: TestCase_getAllFiscalYearsStartAndEndUnixTimes[];
-TEST_CASES_GET_ALL_FISCAL_YEARS_START_AND_END_UNIX_TIMES = importTestData('test_cases_getAllFiscalYearsStartAndEndUnixTimes') as TestCase_getAllFiscalYearsStartAndEndUnixTimes[];
+const TEST_CASES_GET_ALL_FISCAL_YEARS_START_AND_END_UNIX_TIMES: TestCase_getAllFiscalYearsStartAndEndUnixTimes[] =
+    importTestData('test_cases_getAllFiscalYearsStartAndEndUnixTimes') as TestCase_getAllFiscalYearsStartAndEndUnixTimes[];
 
 describe('getAllFiscalYearsStartAndEndUnixTimes', () => {
     TEST_CASES_GET_ALL_FISCAL_YEARS_START_AND_END_UNIX_TIMES.forEach((testCase) => {
-        const fiscalYearStart = FiscalYearStart.strictFromMonthDashDayString(testCase.fiscalYearStart);
+        const fiscalYearStart = FiscalYearStart.parse(testCase.fiscalYearStart);
         test(`returns correct fiscal year start and end unix times for ${getTestTitleFormatString(testCase.fiscalYearStartId, `${testCase.startYearMonth} to ${testCase.endYearMonth}`)}`, () => {
-            const fiscalYearStartAndEndUnixTimes = getAllFiscalYearsStartAndEndUnixTimes(testCase.startYearMonth, testCase.endYearMonth, fiscalYearStart.value);
-            
+            expect(fiscalYearStart).toBeDefined();
+
+            const fiscalYearStartAndEndUnixTimes = getAllFiscalYearsStartAndEndUnixTimes(testCase.startYearMonth, testCase.endYearMonth, fiscalYearStart?.value || 0);
+
             // Convert results to include ISO strings for better test output
             const resultWithISO = fiscalYearStartAndEndUnixTimes.map(data => ({
                 ...data,
                 minUnixTimeISO: formatUnixTimeISO(data.minUnixTime),
                 maxUnixTimeISO: formatUnixTimeISO(data.maxUnixTime)
             }));
-            
+
             // Convert expected to include ISO strings
             const expectedWithISO = testCase.expected.map(data => ({
                 ...data,
                 minUnixTimeISO: formatUnixTimeISO(data.minUnixTime),
                 maxUnixTimeISO: formatUnixTimeISO(data.maxUnixTime)
             }));
-            
+
             expect(resultWithISO).toStrictEqual(expectedWithISO);
         });
     });
@@ -277,15 +274,16 @@ type TestCase_getFiscalYearTimeRangeFromYear = {
     expected: FiscalYearUnixTime;
 }
 
-let TEST_CASES_GET_FISCAL_YEAR_RANGE_FROM_YEAR: TestCase_getFiscalYearTimeRangeFromYear[];
-TEST_CASES_GET_FISCAL_YEAR_RANGE_FROM_YEAR = importTestData('test_cases_getFiscalYearTimeRangeFromYear') as TestCase_getFiscalYearTimeRangeFromYear[];
+const TEST_CASES_GET_FISCAL_YEAR_RANGE_FROM_YEAR: TestCase_getFiscalYearTimeRangeFromYear[] =
+    importTestData('test_cases_getFiscalYearTimeRangeFromYear') as TestCase_getFiscalYearTimeRangeFromYear[];
 
 describe('getFiscalYearTimeRangeFromYear', () => {
     TEST_CASES_GET_FISCAL_YEAR_RANGE_FROM_YEAR.forEach((testCase) => {
-        const fiscalYearStart = FiscalYearStart.strictFromMonthDashDayString(testCase.fiscalYearStart);
+        const fiscalYearStart = FiscalYearStart.parse(testCase.fiscalYearStart);
         test(`returns correct fiscal year unix time range for input year integer ${testCase.year} and FY_START: ${testCase.fiscalYearStart}`, () => {
-            const fiscalYearRange = getFiscalYearTimeRangeFromYear(testCase.year, fiscalYearStart.value);
+            expect(fiscalYearStart).toBeDefined();
+            const fiscalYearRange = getFiscalYearTimeRangeFromYear(testCase.year, fiscalYearStart?.value || 0);
             expect(fiscalYearRange).toStrictEqual(testCase.expected);
         });
     });
-}); 
+});
diff --git a/src/lib/datetime.ts b/src/lib/datetime.ts
index 85c00e5a..3a562130 100644
--- a/src/lib/datetime.ts
+++ b/src/lib/datetime.ts
@@ -442,7 +442,7 @@ export function getAllYearsStartAndEndUnixTimes(startYearMonth: YearMonth | stri
     return allYearTimes;
 }
 
-export function getAllFiscalYearsStartAndEndUnixTimes(startYearMonth: YearMonth | string, endYearMonth: YearMonth | string, fiscalYearStart: number): FiscalYearUnixTime[] {
+export function getAllFiscalYearsStartAndEndUnixTimes(startYearMonth: YearMonth | string, endYearMonth: YearMonth | string, fiscalYearStartValue: number): FiscalYearUnixTime[] {
     // user selects date range: start=2024-01 and end=2026-12
     // result should be 4x FiscalYearUnixTime made up of:
     // - 2024-01->2024-06 (FY 24) - input start year-month->end of fiscal year in which the input start year-month falls
@@ -459,39 +459,45 @@ export function getAllFiscalYearsStartAndEndUnixTimes(startYearMonth: YearMonth
 
     const inputStartUnixTime = getYearMonthFirstUnixTime(range.startYearMonth);
     const inputEndUnixTime = getYearMonthLastUnixTime(range.endYearMonth);
-    const fiscalYearStartMonth = FiscalYearStart.strictFromNumber(fiscalYearStart).month;
-    
+    let fiscalYearStart = FiscalYearStart.valueOf(fiscalYearStartValue);
+
+    if (!fiscalYearStart) {
+        fiscalYearStart = FiscalYearStart.Default;
+    }
+
+    const fiscalYearStartMonth = fiscalYearStart.month;
+
     // Loop over 1 year before and 1 year after the input date range
     // to include fiscal years that start in the previous calendar year.
     for (let year = range.startYearMonth.year - 1; year <= range.endYearMonth.year + 1; year++) {
         const thisYearMonthUnixTime = getYearMonthFirstUnixTime({ year: year, month: fiscalYearStartMonth });
-        const fiscalStartTime = getFiscalYearStartUnixTime(thisYearMonthUnixTime, fiscalYearStart);
-        const fiscalEndTime = getFiscalYearEndUnixTime(thisYearMonthUnixTime, fiscalYearStart);
-    
-        const fiscalYear = getFiscalYearFromUnixTime(fiscalStartTime, fiscalYearStart);
-        
+        const fiscalStartTime = getFiscalYearStartUnixTime(thisYearMonthUnixTime, fiscalYearStart.value);
+        const fiscalEndTime = getFiscalYearEndUnixTime(thisYearMonthUnixTime, fiscalYearStart.value);
+
+        const fiscalYear = getFiscalYearFromUnixTime(fiscalStartTime, fiscalYearStart.value);
+
         if (fiscalStartTime <= inputEndUnixTime && fiscalEndTime >= inputStartUnixTime) {
             let minUnixTime = fiscalStartTime;
             let maxUnixTime = fiscalEndTime;
-            
+
             // Cap the min and max unix times to the input date range
             if (minUnixTime < inputStartUnixTime) {
                 minUnixTime = inputStartUnixTime;
             }
-            
+
             if (maxUnixTime > inputEndUnixTime) {
                 maxUnixTime = inputEndUnixTime;
             }
-            
+
             const fiscalYearTime: FiscalYearUnixTime = {
                 year: fiscalYear,
                 minUnixTime: minUnixTime,
                 maxUnixTime: maxUnixTime,
             };
-            
+
             allFiscalYearTimes.push(fiscalYearTime);
         }
-        
+
         if (fiscalStartTime > inputEndUnixTime) {
             break;
         }
@@ -1010,25 +1016,29 @@ export function isDateRangeMatchOneMonth(minTime: number, maxTime: number): bool
     return isDateRangeMatchFullMonths(minTime, maxTime);
 }
 
-export function getFiscalYearFromUnixTime(unixTime: number, fiscalYearStart: number): number {
+export function getFiscalYearFromUnixTime(unixTime: number, fiscalYearStartValue: number): number {
     const date = moment.unix(unixTime);
-    
+
     // For January 1 fiscal year start, fiscal year matches calendar year
-    if (fiscalYearStart === 0x0101) {
+    if (fiscalYearStartValue === FiscalYearStart.JanuaryFirstDay.value) {
         return date.year();
     }
-    
+
     // Get date components
     const month = date.month() + 1; // 1-index
     const day = date.date();
     const year = date.year();
-    
-    const [fiscalYearStartMonth, fiscalYearStartDay] = FiscalYearStart.strictFromNumber(fiscalYearStart).values();
-    
+
+    let fiscalYearStart = FiscalYearStart.valueOf(fiscalYearStartValue);
+
+    if (!fiscalYearStart) {
+        fiscalYearStart = FiscalYearStart.Default;
+    }
+
     // For other fiscal year starts:
     // If input time comes before the fiscal year start day in the calendar year,
     // it belongs to the fiscal year that ends in the current calendar year
-    if (month < fiscalYearStartMonth || (month === fiscalYearStartMonth && day < fiscalYearStartDay)) {
+    if (month < fiscalYearStart.month || (month === fiscalYearStart.month && day < fiscalYearStart.day)) {
         return year;
     }
 
@@ -1037,33 +1047,38 @@ export function getFiscalYearFromUnixTime(unixTime: number, fiscalYearStart: num
     return year + 1;
 }
 
-export function getFiscalYearStartUnixTime(unixTime: number, fiscalYearStart: number): number {
+export function getFiscalYearStartUnixTime(unixTime: number, fiscalYearStartValue: number): number {
     const date = moment.unix(unixTime);
-    
+
     // For January 1 fiscal year start, fiscal year start time is always January 1 in the input calendar year
-    if (fiscalYearStart === 0x0101) {
+    if (fiscalYearStartValue === FiscalYearStart.JanuaryFirstDay.value) {
         return moment().year(date.year()).month(0).date(1).hour(0).minute(0).second(0).millisecond(0).unix();
     }
 
-    const [fiscalYearStartMonth, fiscalYearStartDay] = FiscalYearStart.strictFromNumber(fiscalYearStart).values();
+    let fiscalYearStart = FiscalYearStart.valueOf(fiscalYearStartValue);
+
+    if (!fiscalYearStart) {
+        fiscalYearStart = FiscalYearStart.Default;
+    }
+
     const month = date.month() + 1; // 1-index
     const day = date.date();
     const year = date.year();
-    
+
     // For other fiscal year starts:
     // If input time comes before the fiscal year start day in the calendar year,
     // the relevant fiscal year has a start date in Calendar Year = Input Year, and end date in Calendar Year = Input Year + 1.
     // If input time comes on or after the fiscal year start day in the calendar year,
     // the relevant fiscal year has a start date in Calendar Year = Input Year - 1, and end date in Calendar Year = Input Year.
     let startYear = year - 1;
-    if (month > fiscalYearStartMonth || (month === fiscalYearStartMonth && day >= fiscalYearStartDay)) {
+    if (month > fiscalYearStart.month || (month === fiscalYearStart.month && day >= fiscalYearStart.day)) {
         startYear = year;
     }
 
     return moment().set({
         year: startYear,
-        month: fiscalYearStartMonth - 1, // 0-index
-        date: fiscalYearStartDay,
+        month: fiscalYearStart.month - 1, // 0-index
+        date: fiscalYearStart.day,
         hour: 0,
         minute: 0,
         second: 0,
@@ -1073,7 +1088,7 @@ export function getFiscalYearStartUnixTime(unixTime: number, fiscalYearStart: nu
 
 export function getFiscalYearEndUnixTime(unixTime: number, fiscalYearStart: number): number {
     const fiscalYearStartTime = moment.unix(getFiscalYearStartUnixTime(unixTime, fiscalYearStart));
-    return fiscalYearStartTime.add(1, 'year').subtract(1, 'second').unix();
+    return fiscalYearStartTime.add(1, 'years').subtract(1, 'seconds').unix();
 }
 
 export function getCurrentFiscalYear(fiscalYearStart: number): number {
@@ -1091,33 +1106,35 @@ export function getFiscalYearTimeRangeFromUnixTime(unixTime: number, fiscalYearS
     };
 }
 
-export function getFiscalYearTimeRangeFromYear(year: number, fiscalYearStart: number): FiscalYearUnixTime {
+export function getFiscalYearTimeRangeFromYear(year: number, fiscalYearStartValue: number): FiscalYearUnixTime {
     const fiscalYear = year;
-    const fiscalYearStartObj = FiscalYearStart.strictFromNumber(fiscalYearStart);
-    
+    let fiscalYearStart = FiscalYearStart.valueOf(fiscalYearStartValue);
+
+    if (!fiscalYearStart) {
+        fiscalYearStart = FiscalYearStart.Default;
+    }
+
     // For a specified fiscal year (e.g., 2023), the start date is in the previous calendar year
     // unless fiscal year starts on January 1
-    const calendarStartYear = fiscalYearStart === 0x0101 ? fiscalYear : fiscalYear - 1;
-    
+    const calendarStartYear = fiscalYearStartValue === FiscalYearStart.JanuaryFirstDay.value ? fiscalYear : fiscalYear - 1;
+
     // Create the timestamp for the start of the fiscal year
     const fiscalYearStartUnixTime = moment().set({
         year: calendarStartYear,
-        month: fiscalYearStartObj.month - 1, // 0-index
-        date: fiscalYearStartObj.day,
+        month: fiscalYearStart.month - 1, // 0-index
+        date: fiscalYearStart.day,
         hour: 0,
         minute: 0,
         second: 0,
         millisecond: 0,
     }).unix();
-    
+
     // Fiscal year end is one year after start minus 1 second
-    const fiscalYearEndUnixTime = moment.unix(fiscalYearStartUnixTime).add(1, 'year').subtract(1, 'second').unix();
-    
+    const fiscalYearEndUnixTime = moment.unix(fiscalYearStartUnixTime).add(1, 'years').subtract(1, 'seconds').unix();
+
     return {
         year: fiscalYear,
         minUnixTime: fiscalYearStartUnixTime,
         maxUnixTime: fiscalYearEndUnixTime,
     };
 }
-
-
diff --git a/src/locales/helpers.ts b/src/locales/helpers.ts
index 6d23f43f..f8ba9173 100644
--- a/src/locales/helpers.ts
+++ b/src/locales/helpers.ts
@@ -935,31 +935,36 @@ export function useI18n() {
         ];
     }
 
-    function getAllFiscalYearFormats(): FiscalYearFormat[] {
+    function getAllFiscalYearFormats(): TypeAndDisplayName[] {
         const now = getCurrentUnixTime();
         let fiscalYearStart = userStore.currentUserFiscalYearStart;
+
         if (!fiscalYearStart) {
             fiscalYearStart = FiscalYearStart.Default.value;
         }
-        const nowFiscalYearRange = getFiscalYearTimeRangeFromUnixTime(now, userStore.currentUserFiscalYearStart);
 
-        const ret: FiscalYearFormat[] = [];
+        const currentFiscalYearRange = getFiscalYearTimeRangeFromUnixTime(now, fiscalYearStart);
+        const ret: TypeAndDisplayName[] = [];
 
-        let defaultFiscalYearFormatType = FiscalYearFormat.parse(t('default.fiscalYearFormat'));
-        if (!defaultFiscalYearFormatType) {
-            defaultFiscalYearFormatType = FiscalYearFormat.Default;
+        let fiscalYearFormat = FiscalYearFormat.parse(getDefaultFiscalYearFormat());
+
+        if (!fiscalYearFormat) {
+            fiscalYearFormat = FiscalYearFormat.Default;
         }
+
         ret.push({
             type: LANGUAGE_DEFAULT_FISCAL_YEAR_FORMAT_VALUE,
-            displayName: `${t('Language Default')} (${formatTimeRangeToFiscalYearFormat(defaultFiscalYearFormatType, nowFiscalYearRange)})`
+            displayName: `${t('Language Default')} (${formatTimeRangeToFiscalYearFormat(fiscalYearFormat, currentFiscalYearRange)})`
         });
 
         const allFiscalYearFormats = FiscalYearFormat.values();
+
         for (let i = 0; i < allFiscalYearFormats.length; i++) {
-            const type = allFiscalYearFormats[i];
+            const format = allFiscalYearFormats[i];
+
             ret.push({
-                type: type.type,
-                displayName: formatTimeRangeToFiscalYearFormat(type, nowFiscalYearRange),
+                type: format.type,
+                displayName: formatTimeRangeToFiscalYearFormat(format, currentFiscalYearRange),
             });
         }
 
@@ -1366,7 +1371,7 @@ export function useI18n() {
         let fiscalYearFormat = FiscalYearFormat.valueOf(userStore.currentUserFiscalYearFormat);
 
         if (!fiscalYearFormat) {
-            const defaultFiscalYearFormatTypeName = t('default.fiscalYearFormat');
+            const defaultFiscalYearFormatTypeName = getDefaultFiscalYearFormat();
             fiscalYearFormat = FiscalYearFormat.parse(defaultFiscalYearFormatTypeName);
 
             if (!fiscalYearFormat) {
@@ -1477,7 +1482,7 @@ export function useI18n() {
             format = FiscalYearFormat.Default;
         }
 
-        return t('format.fiscalYear.' + format.displayName, {
+        return t('format.fiscalYear.' + format.typeName, {
             StartYYYY: formatUnixTime(timeRange.minUnixTime, 'YYYY'),
             StartYY: formatUnixTime(timeRange.minUnixTime, 'YY'),
             EndYYYY: formatUnixTime(timeRange.maxUnixTime, 'YYYY'),
@@ -1493,7 +1498,6 @@ export function useI18n() {
         }
 
         const timeRange = getFiscalYearTimeRangeFromUnixTime(unixTime, userStore.currentUserFiscalYearStart);
-
         return formatTimeRangeToFiscalYearFormat(fiscalYearFormat, timeRange);
     }
 
@@ -1505,18 +1509,17 @@ export function useI18n() {
         }
 
         const timeRange = getFiscalYearTimeRangeFromYear(year, userStore.currentUserFiscalYearStart);
-
         return formatTimeRangeToFiscalYearFormat(fiscalYearFormat, timeRange);
     }
 
-    function formatFiscalYearStart(fiscalYearStart: number) {
-        let fy = FiscalYearStart.fromNumber(fiscalYearStart);
+    function formatFiscalYearStartToLongDay(fiscalYearStartValue: number) {
+        let fiscalYearStart = FiscalYearStart.valueOf(fiscalYearStartValue);
 
-        if ( !fy ) {
-            fy = FiscalYearStart.Default;
+        if (!fiscalYearStart) {
+            fiscalYearStart = FiscalYearStart.Default;
         }
 
-        return formatMonthDayToLongDay(fy.toMonthDashDayString());
+        return formatMonthDayToLongDay(fiscalYearStart.toMonthDashDayString());
     }
 
     function getTimezoneDifferenceDisplayText(utcOffset: number): string {
@@ -1865,7 +1868,6 @@ export function useI18n() {
         getWeekdayLongName,
         getMultiMonthdayShortNames,
         getMultiWeekdayLongNames,
-        getCurrentFiscalYearStartFormatted: () => formatMonthDayToLongDay(FiscalYearStart.strictFromNumber(userStore.currentUserFiscalYearStart).toMonthDashDayString()),
         getCurrentFiscalYearFormatType,
         getCurrentDecimalSeparator,
         getCurrentDigitGroupingSymbol,
@@ -1896,7 +1898,7 @@ export function useI18n() {
         formatMonthDayToLongDay,
         formatYearQuarter,
         formatDateRange,
-        formatFiscalYearStart,
+        formatFiscalYearStartToLongDay,
         formatTimeRangeToFiscalYearFormat,
         formatUnixTimeToFiscalYear,
         formatYearToFiscalYear,
diff --git a/src/views/mobile/users/UserProfilePage.vue b/src/views/mobile/users/UserProfilePage.vue
index 956ae41d..ee8b28aa 100644
--- a/src/views/mobile/users/UserProfilePage.vue
+++ b/src/views/mobile/users/UserProfilePage.vue
@@ -25,6 +25,7 @@
             <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Default Language" title="Language" link="#"></f7-list-item>
             <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Default Currency" title="Currency" link="#"></f7-list-item>
             <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="First Day of Week" title="Week Day" link="#"></f7-list-item>
+            <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Fiscal Year Start Date" title="January 1" link="#"></f7-list-item>
         </f7-list>
 
         <f7-list strong inset dividers class="margin-vertical skeleton-text" v-if="loading">
@@ -32,6 +33,7 @@
             <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Short Date Format" title="YYYY-MM-DD" link="#"></f7-list-item>
             <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Long Time Format" title="HH:mm:ss" link="#"></f7-list-item>
             <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Short Time Format" title="HH:mm" link="#"></f7-list-item>
+            <f7-list-item class="list-item-with-header-and-title list-item-no-item-after" header="Fiscal Year Format" title="FY YYYY" link="#"></f7-list-item>
         </f7-list>
 
         <f7-list strong inset dividers class="margin-vertical skeleton-text" v-if="loading">
@@ -207,7 +209,7 @@
                 link="#"
                 class="list-item-with-header-and-title list-item-no-item-after"
                 :header="tt('Fiscal Year Start Date')"
-                :title="currentFiscalYearStartDate"
+                :title="formatFiscalYearStartToLongDay(newProfile.fiscalYearStart)"
                 @click="showFiscalYearStartSheet = true"
             >
                 <fiscal-year-start-selection-sheet
@@ -516,7 +518,7 @@ const props = defineProps<{
     f7router: Router.Router;
 }>();
 
-const { tt, getAllLanguageOptions, getAllCurrencies, getCurrencyName, formatFiscalYearStart } = useI18n();
+const { tt, getAllLanguageOptions, getAllCurrencies, getCurrencyName, formatFiscalYearStartToLongDay } = useI18n();
 const { showAlert, showToast, routeBackOnError } = useI18nUIComponents();
 
 const {
@@ -597,7 +599,6 @@ const currentLanguageName = computed<string>(() => {
 });
 
 const currentDayOfWeekName = computed<string | null>(() => findDisplayNameByType(allWeekDays.value, newProfile.value.firstDayOfWeek));
-const currentFiscalYearStartDate = computed<string | null>( () => formatFiscalYearStart(newProfile.value.fiscalYearStart) );
 
 function init(): void {
     loading.value = true;
diff --git a/tsconfig.jest.json b/tsconfig.jest.json
new file mode 100644
index 00000000..f1ababab
--- /dev/null
+++ b/tsconfig.jest.json
@@ -0,0 +1,7 @@
+{
+    "extends": "./tsconfig.json",
+    "compilerOptions": {
+        "isolatedModules": true,
+        "verbatimModuleSyntax": false
+    }
+}
diff --git a/tsconfig.json b/tsconfig.json
index 0ce32a71..2ff6f695 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -16,6 +16,7 @@
     },
     "include": [
         "src/**/*",
-        "vite.config.ts"
+        "vite.config.ts",
+        "jest.config.ts"
     ]
 }