From 34361e2f2f341a59b3a29dd99d275515c0c422d4 Mon Sep 17 00:00:00 2001
From: Thomas Kaul <4159106+dtslvr@users.noreply.github.com>
Date: Sun, 2 Aug 2026 16:08:00 +0200
Subject: [PATCH] Refactoring

---
 .../asset-profiles.controller.ts              |  3 +-
 .../asset-profiles/asset-profiles.service.ts  | 13 ++---
 .../asset-profile-split.service.ts            | 47 ++++++------------
 .../asset-profile-dialog.component.ts         | 36 +++++++++-----
 .../asset-profile-dialog.html                 | 27 ++++++++---
 .../dtos/create-asset-profile-split.dto.ts    | 28 +++++++----
 libs/common/src/lib/helper.spec.ts            | 48 ++++++++++++-------
 libs/common/src/lib/helper.ts                 | 23 +++++++--
 .../validator-constraints/is-split-factor.ts  | 17 -------
 .../validator-constraints/is-split-ratio.ts   | 18 +++++++
 .../migration.sql                             |  3 +-
 prisma/schema.prisma                          | 14 ++++--
 12 files changed, 163 insertions(+), 114 deletions(-)
 delete mode 100644 libs/common/src/lib/validator-constraints/is-split-factor.ts
 create mode 100644 libs/common/src/lib/validator-constraints/is-split-ratio.ts

diff --git a/apps/api/src/app/endpoints/asset-profiles/asset-profiles.controller.ts b/apps/api/src/app/endpoints/asset-profiles/asset-profiles.controller.ts
index 62c1b15bac..dd050f6d03 100644
--- a/apps/api/src/app/endpoints/asset-profiles/asset-profiles.controller.ts
+++ b/apps/api/src/app/endpoints/asset-profiles/asset-profiles.controller.ts
@@ -144,7 +144,8 @@ export class AssetProfilesController {
     return this.assetProfilesService.createSplit({
       symbolProfileId,
       date: parseISO(data.date),
-      factor: data.factor
+      denominator: data.denominator,
+      numerator: data.numerator
     });
   }
 
diff --git a/apps/api/src/app/endpoints/asset-profiles/asset-profiles.service.ts b/apps/api/src/app/endpoints/asset-profiles/asset-profiles.service.ts
index 639fe6278a..7d75fc40bb 100644
--- a/apps/api/src/app/endpoints/asset-profiles/asset-profiles.service.ts
+++ b/apps/api/src/app/endpoints/asset-profiles/asset-profiles.service.ts
@@ -42,16 +42,19 @@ export class AssetProfilesService {
 
   public async createSplit({
     date,
-    factor,
+    denominator,
+    numerator,
     symbolProfileId
   }: {
     date: Date;
-    factor: number;
+    denominator: number;
+    numerator: number;
     symbolProfileId: string;
   }) {
     return this.assetProfileSplitService.upsert({
       date,
-      factor,
+      denominator,
+      numerator,
       symbolProfileId
     });
   }
@@ -105,9 +108,7 @@ export class AssetProfilesService {
           symbol
         }
       }),
-      this.assetProfileSplitService.getSplits({
-        assetProfileIdentifiers: [{ dataSource, symbol }]
-      })
+      this.assetProfileSplitService.getSplits({ dataSource, symbol })
     ]);
 
     if (assetProfile) {
diff --git a/apps/api/src/services/asset-profile-split/asset-profile-split.service.ts b/apps/api/src/services/asset-profile-split/asset-profile-split.service.ts
index 46023fccde..ec842caaf5 100644
--- a/apps/api/src/services/asset-profile-split/asset-profile-split.service.ts
+++ b/apps/api/src/services/asset-profile-split/asset-profile-split.service.ts
@@ -5,10 +5,6 @@ import { AssetProfileIdentifier } from '@ghostfolio/common/interfaces';
 import { Injectable } from '@nestjs/common';
 import { AssetProfileSplit } from '@prisma/client';
 
-export type AssetProfileSplitWithAssetProfileIdentifier = AssetProfileSplit & {
-  symbolProfile: AssetProfileIdentifier;
-};
-
 @Injectable()
 export class AssetProfileSplitService {
   public constructor(private readonly prismaService: PrismaService) {}
@@ -35,28 +31,13 @@ export class AssetProfileSplitService {
   }
 
   /**
-   * Returns the splits of the given asset profiles in ascending order by date.
-   * Each split carries the identifier of its asset profile so that the result
-   * can be grouped when querying multiple asset profiles at once.
+   * Returns the splits of the given asset profile in ascending order by date
    */
   public async getSplits({
-    assetProfileIdentifiers
-  }: {
-    assetProfileIdentifiers: AssetProfileIdentifier[];
-  }): Promise<AssetProfileSplitWithAssetProfileIdentifier[]> {
-    if (assetProfileIdentifiers.length === 0) {
-      return [];
-    }
-
+    dataSource,
+    symbol
+  }: AssetProfileIdentifier): Promise<AssetProfileSplit[]> {
     return this.prismaService.assetProfileSplit.findMany({
-      include: {
-        symbolProfile: {
-          select: {
-            dataSource: true,
-            symbol: true
-          }
-        }
-      },
       orderBy: [
         {
           date: 'asc'
@@ -64,12 +45,8 @@ export class AssetProfileSplitService {
       ],
       where: {
         symbolProfile: {
-          OR: assetProfileIdentifiers.map(({ dataSource, symbol }) => {
-            return {
-              dataSource,
-              symbol
-            };
-          })
+          dataSource,
+          symbol
         }
       }
     });
@@ -77,23 +54,27 @@ export class AssetProfileSplitService {
 
   public async upsert({
     date,
-    factor,
+    denominator,
+    numerator,
     symbolProfileId
   }: {
     date: Date;
-    factor: number;
+    denominator: number;
+    numerator: number;
     symbolProfileId: string;
   }): Promise<AssetProfileSplit> {
     const dateOfSplit = resetHours(date);
 
     return this.prismaService.assetProfileSplit.upsert({
       create: {
-        factor,
+        denominator,
+        numerator,
         symbolProfileId,
         date: dateOfSplit
       },
       update: {
-        factor
+        denominator,
+        numerator
       },
       where: {
         symbolProfileId_date: {
diff --git a/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.component.ts b/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.component.ts
index d4d23e9ef9..7e91696c0c 100644
--- a/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.component.ts
+++ b/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.component.ts
@@ -15,7 +15,7 @@ import {
   getStringOrNull,
   getStringOrUndefined,
   isCurrency,
-  isSplitFactor
+  isSplitRatio
 } from '@ghostfolio/common/helper';
 import {
   AdminMarketDataDetails,
@@ -204,17 +204,25 @@ export class GfAssetProfileDialogComponent implements OnInit {
     }
   );
 
-  protected readonly assetProfileSplitForm = this.formBuilder.group({
-    date: new FormControl<Date | null>(null, Validators.required),
-    factor: new FormControl<number | null>(null, [
-      Validators.required,
-      (control: AbstractControl): ValidationErrors | null => {
-        return isSplitFactor(control.value)
+  protected readonly assetProfileSplitForm = this.formBuilder.group(
+    {
+      date: new FormControl<Date | null>(null, Validators.required),
+      denominator: new FormControl<number | null>(null, Validators.required),
+      numerator: new FormControl<number | null>(null, Validators.required)
+    },
+    {
+      validators: (control: AbstractControl): ValidationErrors | null => {
+        const { denominator, numerator } = control.value as {
+          denominator: number;
+          numerator: number;
+        };
+
+        return isSplitRatio({ denominator, numerator })
           ? null
-          : { invalidSplitFactor: true };
+          : { invalidSplitRatio: true };
       }
-    ])
-  });
+    }
+  );
 
   protected readonly canDeleteAssetProfile = canDeleteAssetProfile;
   protected canEditAssetProfile = true;
@@ -550,9 +558,10 @@ export class GfAssetProfileDialogComponent implements OnInit {
   }
 
   protected onAddSplit() {
-    const { date, factor } = this.assetProfileSplitForm.getRawValue();
+    const { date, denominator, numerator } =
+      this.assetProfileSplitForm.getRawValue();
 
-    if (!date || !factor) {
+    if (!date || !denominator || !numerator) {
       return;
     }
 
@@ -560,7 +569,8 @@ export class GfAssetProfileDialogComponent implements OnInit {
       .postAssetProfileSplit({
         dataSource: this.data.dataSource,
         split: {
-          factor,
+          denominator,
+          numerator,
           date: format(date, DATE_FORMAT)
         },
         symbol: this.data.symbol
diff --git a/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.html b/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.html
index 74514a50d8..f79dd8ddab 100644
--- a/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.html
+++ b/apps/client/src/app/components/admin-market-data/asset-profile-dialog/asset-profile-dialog.html
@@ -527,7 +527,7 @@
                           class="mat-mdc-header-cell px-1 py-2 text-right"
                           i18n
                         >
-                          Split Factor
+                          Split Ratio
                         </th>
                         <th class="mat-mdc-header-cell px-1 py-2"></th>
                       </tr>
@@ -539,7 +539,7 @@
                             {{ split.date | date: defaultDateFormat }}
                           </td>
                           <td class="mat-mdc-cell px-1 py-2 text-right">
-                            {{ split.factor }}
+                            {{ split.numerator }}:{{ split.denominator }}
                           </td>
                           <td class="mat-mdc-cell px-1 py-2 text-right">
                             <button
@@ -585,16 +585,29 @@
                     <mat-datepicker #dateOfSplit />
                   </mat-form-field>
                   <mat-form-field appearance="outline" class="mr-3">
-                    <mat-label i18n>Split Factor</mat-label>
+                    <mat-label i18n>Shares After</mat-label>
                     <input
-                      formControlName="factor"
+                      formControlName="numerator"
                       matInput
-                      step="any"
+                      step="1"
                       type="number"
                     />
                     <mat-hint i18n
-                      >Shares after per 1 share before, e.g. 4 for a 4:1 split
-                      or 0.1 for a 1:10 reverse split</mat-hint
+                      >Numerator, e.g. 4 for a 4:1 split or 1 for a 1:10 reverse
+                      split</mat-hint
+                    >
+                  </mat-form-field>
+                  <mat-form-field appearance="outline" class="mr-3">
+                    <mat-label i18n>Shares Before</mat-label>
+                    <input
+                      formControlName="denominator"
+                      matInput
+                      step="1"
+                      type="number"
+                    />
+                    <mat-hint i18n
+                      >Denominator, e.g. 1 for a 4:1 split or 10 for a 1:10
+                      reverse split</mat-hint
                     >
                   </mat-form-field>
                   <button
diff --git a/libs/common/src/lib/dtos/create-asset-profile-split.dto.ts b/libs/common/src/lib/dtos/create-asset-profile-split.dto.ts
index 27bd1364f2..244b5affcb 100644
--- a/libs/common/src/lib/dtos/create-asset-profile-split.dto.ts
+++ b/libs/common/src/lib/dtos/create-asset-profile-split.dto.ts
@@ -1,26 +1,36 @@
 import { IsAfter1970Constraint } from '@ghostfolio/common/validator-constraints/is-after-1970';
-import { IsSplitFactorConstraint } from '@ghostfolio/common/validator-constraints/is-split-factor';
+import { IsSplitRatioConstraint } from '@ghostfolio/common/validator-constraints/is-split-ratio';
 
-import { IsISO8601, IsNumber, Validate } from 'class-validator';
+import { IsInt, IsISO8601, Validate } from 'class-validator';
 
 export class CreateAssetProfileSplitDto {
   /**
    * The date the split becomes effective. Activities before this date are
-   * adjusted by the factor.
+   * adjusted by the ratio.
    */
   @IsISO8601()
   @Validate(IsAfter1970Constraint)
   date: string;
 
   /**
-   * The number of shares held after the split per 1 share held before, for
-   * example 4 for a 4:1 split or 0.1 for a 1:10 reverse split.
+   * The number of shares held before the split, for example 1 for a 4:1 split
+   * or 10 for a 1:10 reverse split.
+   */
+  @IsInt()
+  denominator: number;
+
+  /**
+   * The number of shares held after the split, for example 4 for a 4:1 split
+   * or 1 for a 1:10 reverse split.
+   *
+   * The resulting split factor is numerator / denominator. Both parts are kept
+   * so that the ratio stays exact, for example 1/3 for a 1:3 reverse split.
    *
-   * Only the quantity of activities is adjusted by this factor. Market data is
+   * Only the quantity of activities is adjusted by this ratio. Market data is
    * already split-adjusted by the data providers and must not be adjusted
    * again.
    */
-  @IsNumber()
-  @Validate(IsSplitFactorConstraint)
-  factor: number;
+  @IsInt()
+  @Validate(IsSplitRatioConstraint)
+  numerator: number;
 }
diff --git a/libs/common/src/lib/helper.spec.ts b/libs/common/src/lib/helper.spec.ts
index d123e90f3a..42441a619d 100644
--- a/libs/common/src/lib/helper.spec.ts
+++ b/libs/common/src/lib/helper.spec.ts
@@ -10,7 +10,7 @@ import {
   isAccountExcluded,
   isCurrency,
   isCurrencySymbol,
-  isSplitFactor
+  isSplitRatio
 } from '@ghostfolio/common/helper';
 
 describe('Helper', () => {
@@ -282,34 +282,48 @@ describe('Helper', () => {
     });
   });
 
-  describe('Is split factor', () => {
+  describe('Is split ratio', () => {
     it('Forward split', () => {
-      expect(isSplitFactor(2)).toEqual(true);
-      expect(isSplitFactor(4)).toEqual(true);
+      expect(isSplitRatio({ denominator: 1, numerator: 2 })).toEqual(true);
+      expect(isSplitRatio({ denominator: 1, numerator: 4 })).toEqual(true);
+      expect(isSplitRatio({ denominator: 2, numerator: 3 })).toEqual(true);
     });
 
     it('Reverse split', () => {
-      expect(isSplitFactor(0.1)).toEqual(true);
-      expect(isSplitFactor(0.5)).toEqual(true);
+      expect(isSplitRatio({ denominator: 10, numerator: 1 })).toEqual(true);
+      expect(isSplitRatio({ denominator: 3, numerator: 1 })).toEqual(true);
     });
 
-    it('Factor without effect', () => {
-      expect(isSplitFactor(1)).toEqual(false);
+    it('Ratio without effect', () => {
+      expect(isSplitRatio({ denominator: 1, numerator: 1 })).toEqual(false);
+      expect(isSplitRatio({ denominator: 3, numerator: 3 })).toEqual(false);
     });
 
-    it('Zero or negative factor', () => {
-      expect(isSplitFactor(0)).toEqual(false);
-      expect(isSplitFactor(-2)).toEqual(false);
+    it('Zero or negative ratio', () => {
+      expect(isSplitRatio({ denominator: 1, numerator: 0 })).toEqual(false);
+      expect(isSplitRatio({ denominator: 0, numerator: 1 })).toEqual(false);
+      expect(isSplitRatio({ denominator: 1, numerator: -2 })).toEqual(false);
+      expect(isSplitRatio({ denominator: -2, numerator: 1 })).toEqual(false);
     });
 
-    it('Non-finite factor', () => {
-      expect(isSplitFactor(Number.NaN)).toEqual(false);
-      expect(isSplitFactor(Number.POSITIVE_INFINITY)).toEqual(false);
+    it('Non-integer ratio', () => {
+      expect(isSplitRatio({ denominator: 1, numerator: 1.5 })).toEqual(false);
+      expect(isSplitRatio({ denominator: 2.5, numerator: 1 })).toEqual(false);
+      expect(isSplitRatio({ denominator: 1, numerator: Number.NaN })).toEqual(
+        false
+      );
+      expect(
+        isSplitRatio({ denominator: 1, numerator: Number.POSITIVE_INFINITY })
+      ).toEqual(false);
     });
 
-    it('Missing factor', () => {
-      expect(isSplitFactor(undefined)).toEqual(false);
-      expect(isSplitFactor(null)).toEqual(false);
+    it('Missing ratio', () => {
+      expect(
+        isSplitRatio({ denominator: undefined, numerator: undefined })
+      ).toEqual(false);
+      expect(isSplitRatio({ denominator: null, numerator: null })).toEqual(
+        false
+      );
     });
   });
 });
diff --git a/libs/common/src/lib/helper.ts b/libs/common/src/lib/helper.ts
index 1b41356cb8..22f969d029 100644
--- a/libs/common/src/lib/helper.ts
+++ b/libs/common/src/lib/helper.ts
@@ -527,12 +527,25 @@ export function isRootCurrency(aCurrency: string) {
 }
 
 /**
- * Validates the factor of a stock split, expressed as the number of shares
- * held after the split per 1 share held before, for example 4 for a 4:1 split
- * or 0.1 for a 1:10 reverse split. A factor of 1 would be a no-op.
+ * Validates the ratio of a stock split, expressed as the number of shares held
+ * after the split (numerator) per number of shares held before (denominator),
+ * for example 4 and 1 for a 4:1 split or 1 and 10 for a 1:10 reverse split. An
+ * equal numerator and denominator would be a no-op.
  */
-export function isSplitFactor(aFactor: number) {
-  return Number.isFinite(aFactor) && aFactor > 0 && aFactor !== 1;
+export function isSplitRatio({
+  denominator,
+  numerator
+}: {
+  denominator: number;
+  numerator: number;
+}) {
+  return (
+    Number.isSafeInteger(numerator) &&
+    Number.isSafeInteger(denominator) &&
+    numerator > 0 &&
+    denominator > 0 &&
+    numerator !== denominator
+  );
 }
 
 export function isValidSearchQuery(aQuery: string) {
diff --git a/libs/common/src/lib/validator-constraints/is-split-factor.ts b/libs/common/src/lib/validator-constraints/is-split-factor.ts
deleted file mode 100644
index fd37acd238..0000000000
--- a/libs/common/src/lib/validator-constraints/is-split-factor.ts
+++ /dev/null
@@ -1,17 +0,0 @@
-import { isSplitFactor } from '@ghostfolio/common/helper';
-
-import {
-  ValidatorConstraint,
-  ValidatorConstraintInterface
-} from 'class-validator';
-
-@ValidatorConstraint({ name: 'isSplitFactor' })
-export class IsSplitFactorConstraint implements ValidatorConstraintInterface {
-  public defaultMessage() {
-    return 'factor must be a positive number other than 1';
-  }
-
-  public validate(aFactor: number) {
-    return isSplitFactor(aFactor);
-  }
-}
diff --git a/libs/common/src/lib/validator-constraints/is-split-ratio.ts b/libs/common/src/lib/validator-constraints/is-split-ratio.ts
new file mode 100644
index 0000000000..d3cd454e85
--- /dev/null
+++ b/libs/common/src/lib/validator-constraints/is-split-ratio.ts
@@ -0,0 +1,18 @@
+import { isSplitRatio } from '@ghostfolio/common/helper';
+
+import {
+  ValidationArguments,
+  ValidatorConstraint,
+  ValidatorConstraintInterface
+} from 'class-validator';
+
+@ValidatorConstraint({ name: 'isSplitRatio' })
+export class IsSplitRatioConstraint implements ValidatorConstraintInterface {
+  public defaultMessage() {
+    return 'numerator and denominator must be different positive integers';
+  }
+
+  public validate(_: unknown, { object }: ValidationArguments) {
+    return isSplitRatio(object as { denominator: number; numerator: number });
+  }
+}
diff --git a/prisma/migrations/20260802000000_added_asset_profile_split/migration.sql b/prisma/migrations/20260802000000_added_asset_profile_split/migration.sql
index dd98186571..9003916b4f 100644
--- a/prisma/migrations/20260802000000_added_asset_profile_split/migration.sql
+++ b/prisma/migrations/20260802000000_added_asset_profile_split/migration.sql
@@ -2,8 +2,9 @@
 CREATE TABLE "AssetProfileSplit" (
     "createdAt" TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
     "date" TIMESTAMP(3) NOT NULL,
-    "factor" DOUBLE PRECISION NOT NULL,
+    "denominator" INTEGER NOT NULL,
     "id" TEXT NOT NULL,
+    "numerator" INTEGER NOT NULL,
     "symbolProfileId" TEXT NOT NULL,
     "updatedAt" TIMESTAMP(3) NOT NULL,
 
diff --git a/prisma/schema.prisma b/prisma/schema.prisma
index 359f4332ee..45920b82cd 100644
--- a/prisma/schema.prisma
+++ b/prisma/schema.prisma
@@ -116,18 +116,22 @@ model AssetProfileResolution {
   @@unique([dataSourceOrigin, symbolOrigin])
 }
 
-/// A stock split of an asset profile. The factor is the number of shares held
-/// after the split per 1 share held before, for example 4 for a 4:1 split or
-/// 0.1 for a 1:10 reverse split.
+/// A stock split of an asset profile. The numerator is the number of shares
+/// held after the split, the denominator the number of shares held before, for
+/// example 4 and 1 for a 4:1 split or 1 and 10 for a 1:10 reverse split.
 ///
-/// Only the quantity of activities before the date is adjusted by the factor.
+/// The ratio is stored as two integers instead of the resulting factor, so that
+/// it stays exact, for example 1/3 for a 1:3 reverse split.
+///
+/// Only the quantity of activities before the date is adjusted by the ratio.
 /// Market data is already split-adjusted by the data providers and must not be
 /// adjusted again.
 model AssetProfileSplit {
   createdAt       DateTime      @default(now())
   date            DateTime
-  factor          Float
+  denominator     Int
   id              String        @id @default(uuid())
+  numerator       Int
   symbolProfile   SymbolProfile @relation(fields: [symbolProfileId], onDelete: Cascade, references: [id])
   symbolProfileId String
   updatedAt       DateTime      @updatedAt