import { BaseManager } from '../core/base-manager';
import { ManagerRegistry } from '../core/manager-registry';
import { BottomDockStack } from '../components/bottom-dock-stack';
import { themeManager } from '../services/theme';

export interface BottomDockPanelDefinition {
    id: string;
    title: string;
    closable?: boolean;
    createContent?: () => HTMLElement;
}

export interface BottomDockStateChange {
    id: string;
    open: boolean;
}

type BottomDockStateListener = (state: BottomDockStateChange) => void;

export class BottomDockManager extends BaseManager {
    private stack: BottomDockStack;
    private definitions: Map<string, BottomDockPanelDefinition> = new Map();
    private openStates: Map<string, boolean> = new Map();
    private listeners: Set<BottomDockStateListener> = new Set();
    private unsubscribeTheme: (() => void) | null = null;

    constructor(container: HTMLElement, registry: ManagerRegistry) {
        super(registry);
        this.stack = new BottomDockStack(container);
        this.stack.setTheme(themeManager.getTheme());
        this.unsubscribeTheme = themeManager.subscribe((theme) => {
            this.stack.setTheme(theme);
        });
        this.registerDefaultPanels();
    }

    public register(definition: BottomDockPanelDefinition): void {
        this.definitions.set(definition.id, definition);
        if (!this.openStates.has(definition.id)) {
            this.openStates.set(definition.id, false);
        }
    }

    public unregister(id: string): void {
        if (this.isOpen(id)) {
            this.close(id);
        }
        this.definitions.delete(id);
        this.openStates.delete(id);
    }

    public toggle(id: string): void {
        if (this.isOpen(id)) {
            this.close(id);
            return;
        }
        this.open(id);
    }

    public open(id: string): void {
        const definition = this.definitions.get(id);
        if (!definition) {
            console.warn(`[BottomDock] Unknown panel id: ${id}`);
            return;
        }

        if (this.isOpen(id)) {
            return;
        }

        const content = definition.createContent
            ? definition.createContent()
            : this.stack.createPlaceholderContent(`${definition.title} 面板内容占位`);

        this.stack.addPanel({
            id,
            content,
            closable: definition.closable !== false,
            onClose: () => {
                this.close(id);
            }
        });

        this.openStates.set(id, true);
        this.emitState({ id, open: true });
    }

    public close(id: string): void {
        if (!this.isOpen(id)) {
            return;
        }

        this.stack.removePanel(id);
        this.openStates.set(id, false);
        this.emitState({ id, open: false });
    }

    public isOpen(id: string): boolean {
        return this.openStates.get(id) ?? false;
    }

    public createPlaceholderContent(text: string): HTMLElement {
        return this.stack.createPlaceholderContent(text);
    }

    public onStateChange(listener: BottomDockStateListener): () => void {
        this.listeners.add(listener);
        return () => {
            this.listeners.delete(listener);
        };
    }

    public destroy(): void {
        if (this.unsubscribeTheme) {
            this.unsubscribeTheme();
            this.unsubscribeTheme = null;
        }
        this.listeners.clear();
        this.definitions.clear();
        this.openStates.clear();
        this.stack.destroy();
        super.destroy();
    }

    private emitState(state: BottomDockStateChange): void {
        this.listeners.forEach((listener) => {
            listener(state);
        });
    }

    private registerDefaultPanels(): void {
        this.register({
            id: 'measure',
            title: '测量',
            createContent: () => {
                const measurePanel = this.registry.measureDock?.getPanelElement();
                if (measurePanel) {
                    return measurePanel;
                }
                return this.stack.createPlaceholderContent('测量面板占位');
            }
        });

        this.register({
            id: 'section',
            title: '剖切',
            createContent: () => {
                const sectionPanel = this.registry.sectionDock?.getPanelElement();
                if (sectionPanel) {
                    return sectionPanel;
                }
                return this.stack.createPlaceholderContent('剖切面板占位');
            }
        });

        this.register({
            id: 'walk',
            title: '漫游',
            createContent: () => {
                const walkPanel = this.registry.walkDock?.getPanelElement();
                if (walkPanel) {
                    return walkPanel;
                }
                return this.stack.createPlaceholderContent('漫游面板占位');
            }
        });
    }
}