const Database = require('better-sqlite3');
const path = require('path');
const fs = require('fs');

const dbPath = path.join(__dirname, '../../data');
const db = new Database(path.join(dbPath, 'breedr.db'));

function getDatabase() {
  return db;
}

function initDatabase() {
  db.pragma('foreign_keys = ON');
  db.pragma('journal_mode = WAL');

  // ── Dogs ────────────────────────────────────────────────────────────
  db.exec(`
    CREATE TABLE IF NOT EXISTS dogs (
      id                  INTEGER PRIMARY KEY AUTOINCREMENT,
      name                TEXT NOT NULL,
      registration_number TEXT,
      breed               TEXT NOT NULL,
      sex                 TEXT NOT NULL CHECK(sex IN ('male', 'female')),
      birth_date          TEXT,
      color               TEXT,
      microchip           TEXT,
      litter_id           INTEGER,
      is_active           INTEGER DEFAULT 1,
      is_champion         INTEGER DEFAULT 0,
      photo_urls          TEXT DEFAULT '[]',
      notes               TEXT,
      created_at          TEXT DEFAULT (datetime('now')),
      updated_at          TEXT DEFAULT (datetime('now'))
    )
  `);

  // migrate: add is_champion if missing (safe on existing DBs)
  try {
    db.exec(`ALTER TABLE dogs ADD COLUMN is_champion INTEGER DEFAULT 0`);
  } catch (_) { /* column already exists */ }

  // ── Parents ─────────────────────────────────────────────────────────
  db.exec(`
    CREATE TABLE IF NOT EXISTS parents (
      id          INTEGER PRIMARY KEY AUTOINCREMENT,
      dog_id      INTEGER NOT NULL,
      parent_id   INTEGER NOT NULL,
      parent_type TEXT NOT NULL CHECK(parent_type IN ('sire', 'dam')),
      FOREIGN KEY (dog_id)    REFERENCES dogs(id),
      FOREIGN KEY (parent_id) REFERENCES dogs(id)
    )
  `);

  // ── Breeding Records ────────────────────────────────────────────────
  db.exec(`
    CREATE TABLE IF NOT EXISTS breeding_records (
      id                INTEGER PRIMARY KEY AUTOINCREMENT,
      sire_id           INTEGER NOT NULL,
      dam_id            INTEGER NOT NULL,
      breeding_date     TEXT,
      due_date          TEXT,
      conception_method TEXT CHECK(conception_method IN ('natural', 'ai', 'frozen', 'surgical')),
      notes             TEXT,
      created_at        TEXT DEFAULT (datetime('now')),
      updated_at        TEXT DEFAULT (datetime('now')),
      FOREIGN KEY (sire_id) REFERENCES dogs(id),
      FOREIGN KEY (dam_id)  REFERENCES dogs(id)
    )
  `);

  // ── Litters ─────────────────────────────────────────────────────────
  db.exec(`
    CREATE TABLE IF NOT EXISTS litters (
      id                INTEGER PRIMARY KEY AUTOINCREMENT,
      breeding_id       INTEGER,
      sire_id           INTEGER NOT NULL,
      dam_id            INTEGER NOT NULL,
      whelp_date        TEXT,
      total_count       INTEGER DEFAULT 0,
      male_count        INTEGER DEFAULT 0,
      female_count      INTEGER DEFAULT 0,
      stillborn_count   INTEGER DEFAULT 0,
      notes             TEXT,
      created_at        TEXT DEFAULT (datetime('now')),
      updated_at        TEXT DEFAULT (datetime('now')),
      FOREIGN KEY (breeding_id) REFERENCES breeding_records(id),
      FOREIGN KEY (sire_id)     REFERENCES dogs(id),
      FOREIGN KEY (dam_id)      REFERENCES dogs(id)
    )
  `);

  // ── Health Records ──────────────────────────────────────────────────
  db.exec(`
    CREATE TABLE IF NOT EXISTS health_records (
      id          INTEGER PRIMARY KEY AUTOINCREMENT,
      dog_id      INTEGER NOT NULL,
      record_type TEXT NOT NULL,
      date        TEXT NOT NULL,
      title       TEXT NOT NULL,
      description TEXT,
      vet_name    TEXT,
      notes       TEXT,
      result      TEXT,
      next_due    TEXT,
      created_at  TEXT DEFAULT (datetime('now')),
      updated_at  TEXT DEFAULT (datetime('now')),
      FOREIGN KEY (dog_id) REFERENCES dogs(id)
    )
  `);

  // ── Settings ─────────────────────────────────────────────────────────
  db.exec(`
    CREATE TABLE IF NOT EXISTS settings (
      id              INTEGER PRIMARY KEY AUTOINCREMENT,
      kennel_name     TEXT DEFAULT 'BREEDR',
      kennel_tagline  TEXT,
      kennel_address  TEXT,
      kennel_phone    TEXT,
      kennel_email    TEXT,
      kennel_website  TEXT,
      kennel_akc_id   TEXT,
      kennel_breed    TEXT,
      owner_name      TEXT,
      created_at      TEXT DEFAULT (datetime('now')),
      updated_at      TEXT DEFAULT (datetime('now'))
    )
  `);

  // migrate: add new kennel columns if missing (safe on existing DBs)
  const kennelCols = [
    ['kennel_name',    "TEXT DEFAULT 'BREEDR'"],
    ['kennel_tagline', 'TEXT'],
    ['kennel_address', 'TEXT'],
    ['kennel_phone',   'TEXT'],
    ['kennel_email',   'TEXT'],
    ['kennel_website', 'TEXT'],
    ['kennel_akc_id',  'TEXT'],
    ['kennel_breed',   'TEXT'],
    ['owner_name',     'TEXT'],
  ];
  for (const [col, def] of kennelCols) {
    try {
      db.exec(`ALTER TABLE settings ADD COLUMN ${col} ${def}`);
    } catch (_) { /* already exists */ }
  }

  // Seed a default settings row if none exists
  const existing = db.prepare('SELECT id FROM settings LIMIT 1').get();
  if (!existing) {
    db.prepare(`INSERT INTO settings (kennel_name) VALUES (?)`).run('BREEDR');
  }

  console.log('✓ Database initialized successfully');
}

module.exports = { getDatabase, initDatabase };