fix: channel ordering

fluxer_app/src/components/layout/utils/ChannelMoveOperation.test.tsx

@@ -0,0 +1,180 @@
+/*
+ * Copyright (C) 2026 Fluxer Contributors
+ *
+ * This file is part of Fluxer.
+ *
+ * Fluxer is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Fluxer is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with Fluxer. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import {DND_TYPES, type DragItem, type DropResult} from '@app/components/layout/types/DndTypes';
+import {createChannelMoveOperation} from '@app/components/layout/utils/ChannelMoveOperation';
+import {ChannelRecord} from '@app/records/ChannelRecord';
+import {ChannelTypes} from '@fluxer/constants/src/ChannelConstants';
+import {describe, expect, it} from 'vitest';
+
+const TEST_GUILD_ID = 'guild';
+
+function createChannel(params: {id: string; type: number; position: number; parentId?: string | null}): ChannelRecord {
+	return new ChannelRecord({
+		id: params.id,
+		guild_id: TEST_GUILD_ID,
+		name: params.id,
+		type: params.type,
+		position: params.position,
+		parent_id: params.parentId ?? null,
+	});
+}
+
+function createDragItem(channel: ChannelRecord): DragItem {
+	return {
+		type: DND_TYPES.CHANNEL,
+		id: channel.id,
+		channelType: channel.type,
+		parentId: channel.parentId,
+		guildId: TEST_GUILD_ID,
+	};
+}
+
+describe('ChannelMoveOperation', () => {
+	it('moves a text channel into a voice-only category at the top', () => {
+		const textCategory = createChannel({id: 'text-category', type: ChannelTypes.GUILD_CATEGORY, position: 0});
+		const voiceCategory = createChannel({id: 'voice-category', type: ChannelTypes.GUILD_CATEGORY, position: 1});
+		const generalText = createChannel({
+			id: 'general',
+			type: ChannelTypes.GUILD_TEXT,
+			position: 2,
+			parentId: textCategory.id,
+		});
+		const generalVoice = createChannel({
+			id: 'General',
+			type: ChannelTypes.GUILD_VOICE,
+			position: 3,
+			parentId: voiceCategory.id,
+		});
+
+		const operation = createChannelMoveOperation({
+			channels: [textCategory, voiceCategory, generalText, generalVoice],
+			dragItem: createDragItem(generalText),
+			dropResult: {
+				targetId: voiceCategory.id,
+				position: 'inside',
+				targetParentId: voiceCategory.id,
+			},
+		});
+
+		expect(operation).toEqual({
+			channelId: generalText.id,
+			newParentId: voiceCategory.id,
+			precedingSiblingId: null,
+			position: 0,
+		});
+	});
+
+	it('keeps text channels above voice channels even when dropped after a voice channel', () => {
+		const voiceCategory = createChannel({id: 'voice-category', type: ChannelTypes.GUILD_CATEGORY, position: 0});
+		const generalText = createChannel({id: 'general', type: ChannelTypes.GUILD_TEXT, position: 1});
+		const generalVoice = createChannel({
+			id: 'General',
+			type: ChannelTypes.GUILD_VOICE,
+			position: 2,
+			parentId: voiceCategory.id,
+		});
+
+		const dropResult: DropResult = {
+			targetId: generalVoice.id,
+			position: 'after',
+			targetParentId: voiceCategory.id,
+		};
+		const operation = createChannelMoveOperation({
+			channels: [voiceCategory, generalText, generalVoice],
+			dragItem: createDragItem(generalText),
+			dropResult,
+		});
+
+		expect(operation).toEqual({
+			channelId: generalText.id,
+			newParentId: voiceCategory.id,
+			precedingSiblingId: null,
+			position: 0,
+		});
+	});
+
+	it('keeps moved voice channels below all text siblings', () => {
+		const textCategory = createChannel({id: 'text-category', type: ChannelTypes.GUILD_CATEGORY, position: 0});
+		const voiceCategory = createChannel({id: 'voice-category', type: ChannelTypes.GUILD_CATEGORY, position: 1});
+		const textOne = createChannel({
+			id: 'text-one',
+			type: ChannelTypes.GUILD_TEXT,
+			position: 2,
+			parentId: textCategory.id,
+		});
+		const textTwo = createChannel({
+			id: 'text-two',
+			type: ChannelTypes.GUILD_TEXT,
+			position: 3,
+			parentId: textCategory.id,
+		});
+		const lounge = createChannel({
+			id: 'lounge',
+			type: ChannelTypes.GUILD_VOICE,
+			position: 4,
+			parentId: voiceCategory.id,
+		});
+
+		const operation = createChannelMoveOperation({
+			channels: [textCategory, voiceCategory, textOne, textTwo, lounge],
+			dragItem: createDragItem(lounge),
+			dropResult: {
+				targetId: textOne.id,
+				position: 'before',
+				targetParentId: textCategory.id,
+			},
+		});
+
+		expect(operation).toEqual({
+			channelId: lounge.id,
+			newParentId: textCategory.id,
+			precedingSiblingId: textTwo.id,
+			position: 2,
+		});
+	});
+
+	it('returns null when dropping to the same effective placement', () => {
+		const category = createChannel({id: 'category', type: ChannelTypes.GUILD_CATEGORY, position: 0});
+		const textOne = createChannel({
+			id: 'text-one',
+			type: ChannelTypes.GUILD_TEXT,
+			position: 1,
+			parentId: category.id,
+		});
+		const textTwo = createChannel({
+			id: 'text-two',
+			type: ChannelTypes.GUILD_TEXT,
+			position: 2,
+			parentId: category.id,
+		});
+
+		const operation = createChannelMoveOperation({
+			channels: [category, textOne, textTwo],
+			dragItem: createDragItem(textOne),
+			dropResult: {
+				targetId: textTwo.id,
+				position: 'before',
+				targetParentId: category.id,
+			},
+		});
+
+		expect(operation).toBeNull();
+	});
+});