boss/android/app/src/main/java/com/hyzq/boss/ProjectChatUiState.java

package com.hyzq.boss;

import androidx.annotation.Nullable;

import java.util.Collections;
import java.util.LinkedHashSet;
import java.util.Set;

public final class ProjectChatUiState {
    private ProjectChatUiState() {}

    public static final class SelectionState {
        public final boolean multiSelecting;
        public final Set<String> selectedMessageIds;

        private SelectionState(Set<String> selectedMessageIds) {
            LinkedHashSet<String> normalizedIds = new LinkedHashSet<>(selectedMessageIds);
            this.multiSelecting = !normalizedIds.isEmpty();
            this.selectedMessageIds = Collections.unmodifiableSet(normalizedIds);
        }
    }

    public static boolean canSend(String text, boolean sending) {
        return !sending && text != null && !text.trim().isEmpty();
    }

    public static boolean shouldAutoScroll(boolean nearBottom, boolean forced) {
        return nearBottom || forced;
    }

    public static SelectionState emptySelection() {
        return new SelectionState(new LinkedHashSet<>());
    }

    public static SelectionState selectOnly(String messageId) {
        return toggleSelection(emptySelection(), messageId);
    }

    public static SelectionState toggleSelection(@Nullable SelectionState current, String messageId) {
        if (messageId == null || messageId.trim().isEmpty()) {
            throw new IllegalArgumentException("messageId must not be blank");
        }
        SelectionState state = current == null ? emptySelection() : current;
        LinkedHashSet<String> selectedMessageIds = new LinkedHashSet<>(state.selectedMessageIds);
        if (selectedMessageIds.contains(messageId)) {
            selectedMessageIds.remove(messageId);
            return new SelectionState(selectedMessageIds);
        }
        selectedMessageIds.add(messageId);
        return new SelectionState(selectedMessageIds);
    }

    public static boolean canForwardSelection(@Nullable SelectionState state) {
        return state != null && state.multiSelecting && state.selectedMessageIds.size() >= 2;
    }

    @Nullable
    public static String labelForForwardKind(@Nullable String kind) {
        if ("forward_single".equals(kind)) {
            return "转发";
        }
        if ("forward_bundle".equals(kind)) {
            return "聊天记录";
        }
        return null;
    }
}