/*
 * toolbar.ts — toolbar manager for the ribbit editor.
 *
 * Resolves tags and macros into toolbar buttons. Renders the toolbar
 * DOM. Manages button state (active/disabled/visible).
 *
 * Usage:
 *   const toolbar = editor.toolbar;
 *   toolbar.buttons.get('bold').click();
 *   toolbar.buttons.get('table').hide();
 *   document.body.prepend(toolbar.render());
 */

import type { Tag, ToolbarSlot, Button } from './types';
import type { MacroDef } from './macros';

class ButtonImpl implements Button {
    id: string;
    label: string;
    icon?: string;
    shortcut?: string;
    action: 'wrap' | 'prefix' | 'insert' | 'custom';
    delimiter?: string;
    template?: string;
    replaceSelection: boolean;
    visible: boolean;
    element?: HTMLElement;
    handler?: () => void;

    constructor(def: Partial<Button> & { id: string }) {
        this.id = def.id;
        this.label = def.label || def.id;
        this.icon = def.icon;
        this.shortcut = def.shortcut;
        this.action = def.action || 'insert';
        this.delimiter = def.delimiter;
        this.template = def.template;
        this.replaceSelection = def.replaceSelection ?? true;
        this.visible = def.visible ?? true;
        this.handler = def.handler;
    }

    click(): void {
        this.element?.click();
    }

    hide(): void {
        this.visible = false;
        if (this.element) {
            this.element.style.display = 'none';
        }
    }

    show(): void {
        this.visible = true;
        if (this.element) {
            this.element.style.display = '';
        }
    }
}

export class ToolbarManager {
    buttons: Map<string, Button>;
    private layout: ToolbarSlot[];
    private editor: any;

    constructor(editor: any, tags: Record<string, Tag>, macros: MacroDef[], layout?: ToolbarSlot[]) {
        this.editor = editor;
        this.buttons = new Map();

        for (const tag of Object.values(tags)) {
            if (!tag.button || !tag.button.show) {
                continue;
            }
            this.register(tag.name, {
                label: tag.button.label,
                icon: tag.button.icon,
                shortcut: tag.button.shortcut,
                action: tag.delimiter ? 'wrap' : 'insert',
                delimiter: tag.delimiter,
                template: tag.template,
                replaceSelection: tag.replaceSelection,
            });
        }

        // Heading and list variants (derived from their parent tags)
        for (let i = 1; i <= 6; i++) {
            this.register(`h${i}`, {
                label: `H${i}`,
                shortcut: `Ctrl+${i}`,
                action: 'prefix',
                delimiter: '#'.repeat(i) + ' ',
                replaceSelection: true,
            });
        }
        this.register('ul', {
            label: 'Bullet List',
            shortcut: 'Ctrl+Shift+8',
            action: 'insert',
            template: '- Item 1\n- Item 2\n- Item 3',
            replaceSelection: false,
        });
        this.register('ol', {
            label: 'Numbered List',
            shortcut: 'Ctrl+Shift+7',
            action: 'insert',
            template: '1. Item 1\n2. Item 2\n3. Item 3',
            replaceSelection: false,
        });

        for (const macro of macros) {
            if (macro.button === false) {
                continue;
            }
            const btn = typeof macro.button === 'object' ? macro.button : null;
            this.register(`macro:${macro.name}`, {
                label: btn?.label || macro.name.charAt(0).toUpperCase() + macro.name.slice(1),
                icon: btn?.icon,
                action: 'insert',
                template: `@${macro.name}`,
                replaceSelection: false,
            });
        }

        this.register('save', {
            label: 'Save', shortcut: 'Ctrl+S', action: 'custom',
            handler: () => this.editor.save(),
        });
        this.register('toggle', {
            label: 'Edit', shortcut: 'Ctrl+Shift+V', action: 'custom',
            handler: () => {
                this.editor.getState() === 'view'
                    ? this.editor.wysiwyg()
                    : this.editor.view();
            },
        });
        this.register('markdown', {
            label: 'Source', shortcut: 'Ctrl+/', action: 'custom',
            handler: () => {
                this.editor.getState() === 'edit'
                    ? this.editor.wysiwyg()
                    : this.editor.edit();
            },
        });

        this.layout = layout || this.defaultLayout();
        this.bindShortcuts();
    }

    /**
     * Listen for keyboard shortcuts on the document and dispatch
     * to the matching toolbar button.
     */
    private bindShortcuts(): void {
        const shortcutMap = new Map<string, Button>();
        for (const button of this.buttons.values()) {
            if (button.shortcut) {
                shortcutMap.set(button.shortcut.toLowerCase(), button);
            }
        }

        document.addEventListener('keydown', (event: KeyboardEvent) => {
            const parts: string[] = [];
            if (event.ctrlKey || event.metaKey) parts.push('ctrl');
            if (event.shiftKey) parts.push('shift');
            if (event.altKey) parts.push('alt');

            let key = event.key;
            if (key === '/') key = '/';
            else if (key === '.') key = '.';
            else if (key === '-') key = '-';
            else key = key.toLowerCase();

            parts.push(key);
            const combo = parts.join('+');

            const button = shortcutMap.get(combo);
            if (button) {
                event.preventDefault();
                this.executeAction(button);
            }
        });
    }

    private register(id: string, def: Partial<Button>): void {
        if (this.buttons.has(id)) {
            return;
        }
        this.buttons.set(id, new ButtonImpl({ id, ...def }));
    }

    private defaultLayout(): ToolbarSlot[] {
        const tagIds: string[] = [];
        const macroIds: string[] = [];
        for (const id of this.buttons.keys()) {
            if (['save', 'toggle', 'markdown'].includes(id)) {
                continue;
            }
            if (id.startsWith('macro:')) {
                macroIds.push(id);
            } else {
                tagIds.push(id);
            }
        }
        const slots: ToolbarSlot[] = [...tagIds];
        if (macroIds.length > 0) {
            slots.push('');
            slots.push({ group: 'Macros', items: macroIds });
        }
        slots.push('', 'markdown', 'save', 'toggle');
        return slots;
    }

    /**
     * Update .active class on buttons matching the cursor's formatting context.
     */
    updateActiveState(activeTagNames: string[]): void {
        for (const [id, button] of this.buttons) {
            button.element?.classList.toggle('active', activeTagNames.includes(id));
        }
    }

    /**
     * Enable all toolbar buttons.
     */
    enable(): void {
        for (const button of this.buttons.values()) {
            button.element?.classList.remove('disabled');
        }
    }

    /**
     * Disable all toolbar buttons.
     */
    disable(): void {
        for (const button of this.buttons.values()) {
            button.element?.classList.add('disabled');
        }
    }

    /**
     * Build the toolbar DOM and return it. Caller inserts it.
     */
    render(): HTMLElement {
        const nav = document.createElement('nav');
        nav.className = 'ribbit-toolbar';
        const ul = document.createElement('ul');

        for (const slot of this.layout) {
            if (slot === '') {
                const li = document.createElement('li');
                li.className = 'spacer';
                ul.appendChild(li);
            } else if (typeof slot === 'string') {
                if (slot === 'macros') {
                    const items = [...this.buttons.values()].filter(b => b.id.startsWith('macro:'));
                    if (items.length > 0) {
                        ul.appendChild(this.renderGroup({ label: 'Macros', items }));
                    }
                } else {
                    const button = this.buttons.get(slot);
                    if (button) {
                        ul.appendChild(this.renderButton(button));
                    }
                }
            } else {
                const items = slot.items
                    .map(id => this.buttons.get(id))
                    .filter((b): b is Button => b !== undefined);
                if (items.length > 0) {
                    ul.appendChild(this.renderGroup({ label: slot.group, items }));
                }
            }
        }

        nav.appendChild(ul);
        return nav;
    }

    private renderButton(button: Button): HTMLElement {
        const li = document.createElement('li');
        const btn = document.createElement('button');
        btn.className = `ribbit-btn-${button.id}`;
        btn.textContent = button.label;
        btn.setAttribute('aria-label', button.label);
        btn.title = button.shortcut
            ? `${button.label} (${button.shortcut})`
            : button.label;
        if (!button.visible) {
            li.style.display = 'none';
        }
        btn.addEventListener('click', () => this.executeAction(button));
        button.element = btn;
        li.appendChild(btn);
        return li;
    }

    private renderGroup(group: { label: string; items: Button[] }): HTMLElement {
        const li = document.createElement('li');
        const toggle = document.createElement('button');
        toggle.className = 'ribbit-btn-group';
        toggle.textContent = group.label + ' ▾';
        toggle.setAttribute('aria-label', group.label);
        toggle.title = group.label;

        const menu = document.createElement('div');
        menu.className = 'ribbit-dropdown';
        menu.style.display = 'none';

        for (const button of group.items) {
            const btn = document.createElement('button');
            btn.className = `ribbit-btn-${button.id}`;
            btn.setAttribute('aria-label', button.label);
            btn.title = button.label;
            btn.textContent = button.label;
            if (!button.visible) {
                btn.style.display = 'none';
            }
            btn.addEventListener('click', () => {
                this.executeAction(button);
                menu.style.display = 'none';
            });
            button.element = btn;
            menu.appendChild(btn);
        }

        toggle.addEventListener('click', () => {
            menu.style.display = menu.style.display === 'none' ? '' : 'none';
        });

        li.appendChild(toggle);
        li.appendChild(menu);
        return li;
    }

    private executeAction(button: Button): void {
        if (!button.visible) {
            return;
        }
        if (button.handler) {
            button.handler();
            this.editor.element.focus();
            return;
        }
        if (button.action === 'wrap' && button.delimiter) {
            this.wrapSelection(button.delimiter);
        } else if (button.action === 'insert' && button.template) {
            this.insertText(button.template, button.replaceSelection);
        }
        this.editor.invalidateCache();
        this.editor.element.focus();
    }

    private wrapSelection(delimiter: string): void {
        const sel = window.getSelection();
        if (!sel || sel.rangeCount === 0) {
            return;
        }
        const range = sel.getRangeAt(0);
        const text = range.toString();
        range.deleteContents();
        range.insertNode(document.createTextNode(delimiter + text + delimiter));
    }

    private insertText(text: string, replaceSelection: boolean): void {
        const sel = window.getSelection();
        if (!sel || sel.rangeCount === 0) {
            return;
        }
        const range = sel.getRangeAt(0);
        if (replaceSelection) {
            range.deleteContents();
        } else {
            range.collapse(false);
        }
        range.insertNode(document.createTextNode(text));
    }
}