// ═══════════════════════════════════════════════════════════════════════
// ABILITIES — spell & skill unlock guide for abilities page
// ═══════════════════════════════════════════════════════════════════════

function enhanceAbilities() {
    if (document.getElementById('hv-abilities')) return;

    const lv = STATE.level || 1;

    // Detect current tree
    const url = window.location.href || '';
    const treeMap = {
        'tree=general': 'General',
        'tree=onehanded': 'One-Handed',
        'tree=twohanded': 'Two-Handed',
        'tree=dualwield': 'Dual Wield',
        'tree=niten': 'Niten',
        'tree=staff': 'Staff',
        'tree=cloth': 'Cloth',
        'tree=light': 'Light',
        'tree=heavy': 'Heavy',
        'tree=deprecating1': 'Deprecating 1',
        'tree=deprecating2': 'Deprecating 2',
        'tree=supportive1': 'Supportive 1',
        'tree=supportive2': 'Supportive 2',
        'tree=elemental': 'Elemental',
        'tree=forbidden': 'Forbidden',
        'tree=divine': 'Divine',
    };
    let tree = 'General';
    for (const [k, v] of Object.entries(treeMap)) {
        if (url.includes(k)) { tree = v; break; }
    }

    // Read AP from CSS-digit counter
    let ap = 0;
    $$('#ability_top [class*="f4b"]').some(div => {
        const txt = div.textContent || '';
        if (txt.includes('Ability') || txt.includes('Mastery')) {
            const d = readCSSDigits(div);
            if (d !== null) ap = d;
            return true;
        }
    });

    // Parse all visible abilities
    const abilities = [];
    $$('[id^="slot_"][onmouseover]').forEach(el => {
        const mo = el.getAttribute('onmouseover') || '';
        const m = mo.match(/overability\((\d+),\s*'([^']+)',\s*'([^']*)',\s*'([^']*)',\s*'([^']*)'/);
        if (!m) return;

        const name = m[2];
        const status = m[4];
        const nextHtml = m[5];
        const lvlMatch = nextHtml.match(/Level\s*(\d+)/i);
        const lvlReq = lvlMatch ? parseInt(lvlMatch[1]) : 0;
        const apMatch = nextHtml.match(/(\d+)\s*Ability\s*Points?/i);
        const apCost = apMatch ? parseInt(apMatch[1]) : 0;
        const tierMatch = status.match(/Tier\s*(\d+)/i);
        const curTier = tierMatch ? parseInt(tierMatch[1]) : 0;
        const acquired = status !== 'Not Acquired' && status !== 'Locked';

        abilities.push({ name, status, acquired, curTier, lvlReq, apCost, el });
    });

    // Free slots
    const freeSlots = $$('#ability_top [id^="slot_"]').filter(el => {
        return (el.style.backgroundImage || '').includes('t/0.png');
    }).length;

    // Build panel
    let body = `<b>💎 AP: ${ap}</b><br>`;
    if (freeSlots > 0) {
        body += `<div style="color:#f88;font-size:9px">⚠ ${freeSlots} empty slots — assign abilities!</div>`;
    }

    body += `<div style="border-top:1px solid #374151;margin:4px 0;padding:4px 0"><b>🌳 ${tree}</b>`;

    const affordable = abilities.filter(a => !a.acquired && lv >= a.lvlReq && ap >= a.apCost);
    const lockedByLevel = abilities.filter(a => !a.acquired && lv < a.lvlReq);
    const owned = abilities.filter(a => a.acquired);

    if (owned.length > 0) body += `<div style="color:#8f8;font-size:9px">✅ ${owned.length} owned</div>`;
    if (affordable.length > 0) {
        const best = affordable.sort((a, b) => a.apCost - b.apCost)[0];
        body += `<div style="color:#0f0;font-size:9px">⬆ <b>Buy: ${best.name}</b> (${best.apCost} AP)</div>`;
    }
    if (lockedByLevel.length > 0) {
        const next = lockedByLevel.sort((a, b) => a.lvlReq - b.lvlReq)[0];
        body += `<div style="color:#fdcb00;font-size:9px">🔒 ${next.name} @ Lv${next.lvlReq}</div>`;
    }
    body += `</div>`;

    // Full table
    if (abilities.length > 0) {
        body += `<div style="border-top:1px solid #374151;margin:4px 0;padding:4px 0;font-size:9px">
            <table style="width:100%;border-collapse:collapse">
            <tr style="color:#888"><th style="text-align:left;padding:1px 4px">Ability</th>
            <th style="padding:1px 4px">AP</th><th style="padding:1px 4px">Lv</th>
            <th style="text-align:right;padding:1px 4px">Status</th></tr>`;

        const sorted = [].concat(
            affordable.sort((a, b) => a.apCost - b.apCost),
            owned,
            lockedByLevel.sort((a, b) => a.lvlReq - b.lvlReq),
        );

        const seen = new Set();
        for (const a of sorted) {
            const k = a.name + a.curTier;
            if (seen.has(k)) continue;
            seen.add(k);
            const color = a.acquired ? '#8f8'
                : (lv >= a.lvlReq && ap >= a.apCost) ? '#0f0'
                : lv >= a.lvlReq ? '#fdcb00' : '#888';
            const lbl = a.acquired ? `T${a.curTier}`
                : (lv >= a.lvlReq && ap >= a.apCost) ? '⬆ Buy'
                : lv >= a.lvlReq ? '🔒AP' : `Lv${a.lvlReq}`;
            body += `<tr><td style="padding:1px 4px;color:${color}">${a.name}</td>
                <td style="padding:1px 4px;color:#888">${a.apCost}</td>
                <td style="padding:1px 4px;color:#888">${a.lvlReq}</td>
                <td style="padding:1px 4px;text-align:right;color:${color}">${lbl}</td></tr>`;
        }
        body += `</table></div>`;
    }

    // Global priority
    body += `<div style="border-top:1px solid #374151;margin:4px 0;padding:4px 0;font-size:9px;color:#888">
        <b>🗺 Priority:</b> General (Tanks) → Supportive → Weapon → Elemental → Deprecating<br>
        Visit each tree tab for detailed recommendations.
    </div>`;

    const panel = document.createElement('div');
    panel.id = 'hv-abilities';
    panel.style.cssText = css({
        position: 'fixed',
        top: '60px',
        right: '4px',
        zIndex: '9995',
        background: '#111827',
        color: '#d1d5db',
        padding: '0',
        borderRadius: '8px',
        fontSize: '10px',
        fontFamily: 'monospace',
        maxWidth: '320px',
        boxShadow: '0 0 15px rgba(0,0,0,0.6)',
        border: '1px solid #374151',
    });

    const collapsed = localStorage[SP + 'abCollapsed'] === '1';
    panel.innerHTML = `<div style="display:flex;justify-content:space-between;align-items:center;padding:6px 8px;cursor:pointer" id="hv-ab-header">
        <b style="color:#fdcb00;font-size:10px">📖 Abilities (Lv${lv})</b>
        <span id="hv-ab-toggle" style="color:#888;font-size:12px">${collapsed ? '▶' : '▼'}</span>
    </div>
    <div id="hv-ab-body" style="padding:0 8px 6px;display:${collapsed ? 'none' : 'block'}">${body}</div>`;

    panel.querySelector('#hv-ab-header').onclick = () => {
        const b = document.getElementById('hv-ab-body');
        const t = document.getElementById('hv-ab-toggle');
        const h = b.style.display === 'none';
        b.style.display = h ? 'block' : 'none';
        t.textContent = h ? '▼' : '▶';
        localStorage[SP + 'abCollapsed'] = h ? '0' : '1';
    };

    document.body.appendChild(panel);
}