// BlockInspector — compact horizontal strip for editing selected block params
// Appears between timeline canvas and transport bar when a block is selected.
// All parameter changes go through UpdateParamsCommand for full undo/redo support.

import { UpdateParamsCommand } from './commands.js';

export class BlockInspector {
    constructor(containerEl, history) {
        this.el = containerEl;       // #block-inspector div
        this.history = history;      // CommandHistory reference
        this.tracks = null;          // set by app.js from timeline.tracks
        this.currentBlock = null;
        this._onDelete = null;       // callback(block) — set by app.js
    }

    show(block) {
        this.currentBlock = block;
        if (!block) {
            this.el.style.display = 'none';
            return;
        }
        this.el.style.display = 'flex';
        this._render(block);
    }

    hide() {
        this.currentBlock = null;
        this.el.style.display = 'none';
    }

    _render(block) {
        const animName = (block.animation || 'BLOCK').toUpperCase().replace(/_/g, ' ');
        const color = block.params?.color || '#00ffff';
        const speed = block.params?.speed ?? 1.0;
        const direction = block.params?.direction || 'forward';
        const length = block.params?.length ?? 0.3;

        this.el.innerHTML = `
            <span class="inspector-label">${animName}</span>
            <label class="inspector-field">
                COLOR
                <div class="inspector-color-swatch" id="color-swatch" style="background:${color};" title="Click to change color"></div>
                <input type="color" id="inspector-color" value="${color}" style="display:none;">
            </label>
            <label class="inspector-field">
                SPEED
                <input type="number" id="inspector-speed" step="0.1" min="0.1" max="10" value="${speed}">
            </label>
            <label class="inspector-field">
                DIR
                <select id="inspector-direction">
                    <option value="forward" ${direction === 'forward' ? 'selected' : ''}>FWD</option>
                    <option value="reverse" ${direction === 'reverse' ? 'selected' : ''}>REV</option>
                </select>
            </label>
            <label class="inspector-field">
                LEN
                <input type="number" id="inspector-length" step="0.05" min="0.05" max="1" value="${length}">
            </label>
            <div style="flex:1"></div>
            <button class="inspector-remove" title="Remove block">&#10005;</button>
        `;

        this._wireEvents(block);
    }

    _wireEvents(block) {
        // Color swatch → open hidden color input
        const swatch = this.el.querySelector('#color-swatch');
        const colorInput = this.el.querySelector('#inspector-color');
        swatch?.addEventListener('click', () => colorInput?.click());

        // Live preview: update swatch as color drags
        colorInput?.addEventListener('input', (e) => {
            swatch.style.background = e.target.value;
        });
        // Commit on change (not during drag — avoids command flood)
        colorInput?.addEventListener('change', (e) => {
            const oldParams = { ...block.params };
            const newParams = { ...block.params, color: e.target.value };
            const cmd = new UpdateParamsCommand(this.tracks, block, oldParams, newParams);
            this.history.execute(cmd);
        });

        // Speed
        this.el.querySelector('#inspector-speed')?.addEventListener('change', (e) => {
            const val = parseFloat(e.target.value);
            if (isNaN(val) || val < 0.1 || val > 10) return;
            const oldParams = { ...block.params };
            const newParams = { ...block.params, speed: val };
            const cmd = new UpdateParamsCommand(this.tracks, block, oldParams, newParams);
            this.history.execute(cmd);
        });

        // Direction
        this.el.querySelector('#inspector-direction')?.addEventListener('change', (e) => {
            const oldParams = { ...block.params };
            const newParams = { ...block.params, direction: e.target.value };
            const cmd = new UpdateParamsCommand(this.tracks, block, oldParams, newParams);
            this.history.execute(cmd);
        });

        // Length
        this.el.querySelector('#inspector-length')?.addEventListener('change', (e) => {
            const val = parseFloat(e.target.value);
            if (isNaN(val) || val < 0.05 || val > 1) return;
            const oldParams = { ...block.params };
            const newParams = { ...block.params, length: val };
            const cmd = new UpdateParamsCommand(this.tracks, block, oldParams, newParams);
            this.history.execute(cmd);
        });

        // Remove button
        this.el.querySelector('.inspector-remove')?.addEventListener('click', () => {
            if (this._onDelete) this._onDelete(block);
        });
    }
}