import * as api from '../api.js';

const el = () => document.getElementById('page-dashboard');

export function initDashboard() {
    el().innerHTML = `
        <h1 class="page-title">Dashboard</h1>
        <div id="dash-active-task"></div>
        <div class="section-title mt-16">Task Summary</div>
        <div id="dash-stats" class="stats-grid"></div>
        <div class="section-title mt-16">Recent Activity (8 hours)</div>
        <div id="dash-context" class="card"></div>`;
}

export async function refreshDashboard() {
    try {
        const [active, allTasks, summary] = await Promise.all([
            api.tasks.active(),
            api.tasks.list(null, { includeSubTasks: true }),
            api.context.summary(),
        ]);
        await renderActiveTask(active);
        renderStats(allTasks);
        renderContextSummary(summary);
    } catch (e) {
        console.error('Dashboard refresh failed:', e);
    }
}

async function buildParentTrail(task) {
    const trail = [];
    let current = task;
    while (current.parentTaskId) {
        try {
            current = await api.tasks.get(current.parentTaskId);
            trail.unshift({ id: current.id, title: current.title });
        } catch {
            break;
        }
    }
    return trail;
}

async function renderActiveTask(task) {
    const container = document.getElementById('dash-active-task');
    if (!task) {
        container.innerHTML = `<div class="card"><div class="no-active-task">No active task</div></div>`;
        return;
    }

    const parentTrail = await buildParentTrail(task);
    const breadcrumbHtml = parentTrail.length > 0
        ? `<div class="breadcrumb text-sm mt-8">${parentTrail.map(p => `<span class="breadcrumb-parent">${esc(p.title)}</span><span class="breadcrumb-sep">/</span>`).join('')}<span class="breadcrumb-current">${esc(task.title)}</span></div>`
        : '';

    const elapsed = task.startedAt ? formatElapsed(new Date(task.startedAt)) : '';
    container.innerHTML = `
        <div class="card active-task-card">
            <div class="card-header">
                <div>
                    <div class="card-title">${esc(task.title)}</div>
                    ${breadcrumbHtml}
                    ${task.description ? `<div class="text-sm text-muted mt-8">${esc(task.description)}</div>` : ''}
                    ${task.category ? `<div class="text-sm text-muted">Category: ${esc(task.category)}</div>` : ''}
                    ${elapsed ? `<div class="text-sm text-muted">Active for ${elapsed}</div>` : ''}
                </div>
                <div class="btn-group">
                    <button class="btn btn-warning btn-sm" data-action="pause" data-id="${task.id}">Pause</button>
                    <button class="btn btn-success btn-sm" data-action="complete" data-id="${task.id}">Complete</button>
                </div>
            </div>
        </div>`;
    container.querySelectorAll('[data-action]').forEach(btn => {
        btn.addEventListener('click', async () => {
            const action = btn.dataset.action;
            const id = btn.dataset.id;
            try {
                if (action === 'pause') await api.tasks.pause(id);
                else if (action === 'complete') await api.tasks.complete(id);
                refreshDashboard();
            } catch (e) { alert(e.message); }
        });
    });
}

function renderStats(allTasks) {
    const counts = { Pending: 0, Active: 0, Paused: 0, Completed: 0, Abandoned: 0 };
    allTasks.forEach(t => counts[t.status] = (counts[t.status] || 0) + 1);
    const container = document.getElementById('dash-stats');
    container.innerHTML = Object.entries(counts).map(([status, count]) => `
        <div class="stat-card">
            <div class="stat-value">${count}</div>
            <div class="stat-label">${status}</div>
        </div>`).join('');
}

function renderContextSummary(summary) {
    const container = document.getElementById('dash-context');
    if (!summary || summary.length === 0) {
        container.innerHTML = `<div class="empty-state">No recent activity</div>`;
        return;
    }
    container.innerHTML = summary.slice(0, 10).map(item => `
        <div class="summary-item">
            <div>
                <div class="summary-app">${esc(item.appName)}</div>
                <div class="summary-category">${esc(item.category)}</div>
            </div>
            <div class="summary-count">${item.eventCount}</div>
        </div>`).join('');
}

function formatElapsed(since) {
    const diff = Math.floor((Date.now() - since.getTime()) / 1000);
    if (diff < 60) return `${diff}s`;
    if (diff < 3600) return `${Math.floor(diff / 60)}m`;
    const h = Math.floor(diff / 3600);
    const m = Math.floor((diff % 3600) / 60);
    return `${h}h ${m}m`;
}

function esc(str) {
    if (!str) return '';
    const d = document.createElement('div');
    d.textContent = str;
    return d.innerHTML;
}