import { Router } from 'express';
import db from '../db/index.js';

const router = Router();

// Rarity spawn weights (common -> legendary). Mirrors the project's
// common(7)/rare(3)/legendary(1) weighting, mapped onto the 4 star tiers.
const RARITY_WEIGHTS = { 1: 7, 2: 4, 3: 3, 4: 1 };

function rowToGhost(g) {
  return {
    id: g.id,
    name: g.name,
    displayName: g.display_name || g.name,
    type: g.type,
    rarity: g.rarity,
    speed: g.speed,
    range: g.range,
    chargeShot: g.charge_shot,
    health: g.health,
    damage: g.damage,
    ability: g.ability,
    isBoss: !!g.is_boss,
    setNumber: g.set_number,
    setName: g.set_name,
    image: g.image_path ? `/uploads/${g.image_path}` : null,
    webm: g.webm_path ? `/uploads/${g.webm_path}` : null,
    webp: g.webp_path ? `/uploads/${g.webp_path}` : null,
  };
}

function weightedPick(ghosts) {
  const weighted = [];
  for (const g of ghosts) {
    const w = RARITY_WEIGHTS[g.rarity] ?? 1;
    for (let i = 0; i < w; i++) weighted.push(g);
  }
  if (!weighted.length) return null;
  return weighted[Math.floor(Math.random() * weighted.length)];
}

// GET /api/scan/:code  — no auth. Returns the set's ghost roster + boss.
router.get('/scan/:code', (req, res) => {
  const set = db
    .prepare('SELECT * FROM sets WHERE code = ? AND enabled = 1')
    .get(req.params.code);
  if (!set) return res.status(404).json({ error: 'unknown or disabled set code' });

  const roster = db
    .prepare(
      `SELECT g.* FROM ghosts g
       JOIN set_ghosts sg ON sg.ghost_id = g.id
       WHERE sg.set_id = ? AND g.enabled = 1
       ORDER BY g.is_boss DESC, g.rarity DESC, g.name`
    )
    .all(set.id);

  const boss = set.boss_ghost_id
    ? db.prepare('SELECT * FROM ghosts WHERE id = ?').get(set.boss_ghost_id)
    : null;

  res.json({
    set: {
      code: set.code,
      setNumber: set.set_number,
      setName: set.set_name,
    },
    boss: boss ? rowToGhost(boss) : null,
    roster: roster.map(rowToGhost),
  });
});

// GET /api/freehunt  — no auth. Spawns N weighted random enabled non-boss ghosts
// for free-hunt mode (procedural wisps client-side if no image).
router.get('/freehunt', (req, res) => {
  const n = Math.min(parseInt(req.query.n, 10) || 3, 10);
  const type = req.query.type; // optional red|yellow|blue filter
  // Free hunt only spawns ghosts with an uploaded video (webm); the webp/image
  // fallbacks are derived from it, so these always render on every platform.
  let q = 'SELECT * FROM ghosts WHERE enabled = 1 AND is_boss = 0 AND webm_path IS NOT NULL';
  const params = [];
  if (type && ['red', 'yellow', 'blue'].includes(type)) {
    q += ' AND type = ?';
    params.push(type);
  }
  const pool = db.prepare(q).all(...params);
  const spawns = [];
  for (let i = 0; i < n && pool.length; i++) {
    const pick = weightedPick(pool);
    if (pick) spawns.push(rowToGhost(pick));
  }
  res.json({ spawns });
});

// GET /api/ghosts  — no auth. Public roster browser (enabled only).
router.get('/ghosts', (req, res) => {
  const { type, rarity, boss } = req.query;
  let q = 'SELECT * FROM ghosts WHERE enabled = 1';
  const params = [];
  if (type) { q += ' AND type = ?'; params.push(type); }
  if (rarity) { q += ' AND rarity = ?'; params.push(parseInt(rarity, 10)); }
  if (boss === '1') q += ' AND is_boss = 1';
  q += ' ORDER BY type, rarity, name';
  res.json({ ghosts: db.prepare(q).all(...params).map(rowToGhost) });
});

// GET /api/abilities — no auth. Reference data.
router.get('/abilities', (req, res) => {
  const rows = db.prepare('SELECT * FROM abilities ORDER BY kind, name').all();
  res.json({ abilities: rows });
});

export default router;