import { DatabaseSync } from 'node:sqlite';
import { mkdirSync } from 'fs';
import { dirname, join } from 'path';
import { fileURLToPath } from 'url';

const __dirname = dirname(fileURLToPath(import.meta.url));
const DEFAULT_PATH = join(__dirname, '../data/catalyst.db');

let db;

function init(path) {
  if (path !== ':memory:') {
    mkdirSync(dirname(path), { recursive: true });
  }
  db = new DatabaseSync(path);
  db.exec('PRAGMA journal_mode = WAL');
  db.exec('PRAGMA foreign_keys = ON');
  db.exec('PRAGMA synchronous = NORMAL');
  createSchema();
  if (path !== ':memory:') seed();
}

function createSchema() {
  db.exec(`
    CREATE TABLE IF NOT EXISTS instances (
      id                    INTEGER PRIMARY KEY AUTOINCREMENT,
      name                  TEXT    NOT NULL CHECK(length(name) BETWEEN 1 AND 100),
      state                 TEXT    NOT NULL DEFAULT 'deployed'
                                    CHECK(state IN ('deployed','testing','degraded')),
      stack                 TEXT    NOT NULL DEFAULT 'development'
                                    CHECK(stack IN ('production','development')),
      vmid                  INTEGER NOT NULL UNIQUE CHECK(vmid > 0),
      atlas                 INTEGER NOT NULL DEFAULT 0 CHECK(atlas IN (0,1)),
      argus                 INTEGER NOT NULL DEFAULT 0 CHECK(argus IN (0,1)),
      semaphore             INTEGER NOT NULL DEFAULT 0 CHECK(semaphore IN (0,1)),
      patchmon              INTEGER NOT NULL DEFAULT 0 CHECK(patchmon IN (0,1)),
      tailscale             INTEGER NOT NULL DEFAULT 0 CHECK(tailscale IN (0,1)),
      andromeda             INTEGER NOT NULL DEFAULT 0 CHECK(andromeda IN (0,1)),
      tailscale_ip          TEXT    NOT NULL DEFAULT '',
      hardware_acceleration INTEGER NOT NULL DEFAULT 0 CHECK(hardware_acceleration IN (0,1)),
      created_at            TEXT    NOT NULL DEFAULT (datetime('now')),
      updated_at            TEXT    NOT NULL DEFAULT (datetime('now'))
    );
    CREATE INDEX IF NOT EXISTS idx_instances_state ON instances(state);
    CREATE INDEX IF NOT EXISTS idx_instances_stack ON instances(stack);
  `);
}

const SEED = [
  { name: 'plex',             state: 'deployed',  stack: 'production',  vmid: 117, atlas: 1, argus: 1, semaphore: 0, patchmon: 1, tailscale: 1, andromeda: 0, tailscale_ip: '100.64.0.1',  hardware_acceleration: 1 },
  { name: 'foldergram',       state: 'testing',   stack: 'development', vmid: 137, atlas: 0, argus: 0, semaphore: 0, patchmon: 0, tailscale: 0, andromeda: 0, tailscale_ip: '',            hardware_acceleration: 0 },
  { name: 'homeassistant',    state: 'deployed',  stack: 'production',  vmid: 102, atlas: 1, argus: 1, semaphore: 1, patchmon: 1, tailscale: 1, andromeda: 0, tailscale_ip: '100.64.0.5',  hardware_acceleration: 0 },
  { name: 'gitea',            state: 'deployed',  stack: 'production',  vmid: 110, atlas: 1, argus: 0, semaphore: 1, patchmon: 1, tailscale: 1, andromeda: 0, tailscale_ip: '100.64.0.8',  hardware_acceleration: 0 },
  { name: 'postgres-primary', state: 'degraded',  stack: 'production',  vmid: 201, atlas: 1, argus: 1, semaphore: 0, patchmon: 1, tailscale: 0, andromeda: 1, tailscale_ip: '',            hardware_acceleration: 0 },
  { name: 'nextcloud',        state: 'testing',   stack: 'development', vmid: 144, atlas: 0, argus: 0, semaphore: 0, patchmon: 0, tailscale: 1, andromeda: 0, tailscale_ip: '100.64.0.12', hardware_acceleration: 0 },
  { name: 'traefik',          state: 'deployed',  stack: 'production',  vmid: 100, atlas: 1, argus: 1, semaphore: 0, patchmon: 1, tailscale: 1, andromeda: 0, tailscale_ip: '100.64.0.2',  hardware_acceleration: 0 },
  { name: 'monitoring-stack', state: 'testing',   stack: 'development', vmid: 155, atlas: 0, argus: 0, semaphore: 1, patchmon: 0, tailscale: 0, andromeda: 0, tailscale_ip: '',            hardware_acceleration: 0 },
];

function seed() {
  const count = db.prepare('SELECT COUNT(*) as n FROM instances').get().n;
  if (count > 0) return;
  const insert = db.prepare(`
    INSERT INTO instances
      (name, state, stack, vmid, atlas, argus, semaphore, patchmon,
       tailscale, andromeda, tailscale_ip, hardware_acceleration)
    VALUES
      (@name, @state, @stack, @vmid, @atlas, @argus, @semaphore, @patchmon,
       @tailscale, @andromeda, @tailscale_ip, @hardware_acceleration)
  `);
  db.exec('BEGIN');
  for (const s of SEED) insert.run(s);
  db.exec('COMMIT');
}

// ── Queries ───────────────────────────────────────────────────────────────────

export function getInstances(filters = {}) {
  const parts = ['SELECT * FROM instances WHERE 1=1'];
  const params = {};
  if (filters.search) {
    parts.push('AND (name LIKE @search OR CAST(vmid AS TEXT) LIKE @search OR stack LIKE @search)');
    params.search = `%${filters.search}%`;
  }
  if (filters.state) { parts.push('AND state = @state'); params.state = filters.state; }
  if (filters.stack) { parts.push('AND stack = @stack'); params.stack = filters.stack; }
  parts.push('ORDER BY name ASC');
  return db.prepare(parts.join(' ')).all(params);
}

export function getInstance(vmid) {
  return db.prepare('SELECT * FROM instances WHERE vmid = ?').get(vmid) ?? null;
}

export function getDistinctStacks() {
  return db.prepare(`SELECT DISTINCT stack FROM instances WHERE stack != '' ORDER BY stack`)
    .all().map(r => r.stack);
}

// ── Mutations ─────────────────────────────────────────────────────────────────

export function createInstance(data) {
  return db.prepare(`
    INSERT INTO instances
      (name, state, stack, vmid, atlas, argus, semaphore, patchmon,
       tailscale, andromeda, tailscale_ip, hardware_acceleration)
    VALUES
      (@name, @state, @stack, @vmid, @atlas, @argus, @semaphore, @patchmon,
       @tailscale, @andromeda, @tailscale_ip, @hardware_acceleration)
  `).run(data);
}

export function updateInstance(vmid, data) {
  return db.prepare(`
    UPDATE instances SET
      name=@name, state=@state, stack=@stack, vmid=@newVmid,
      atlas=@atlas, argus=@argus, semaphore=@semaphore, patchmon=@patchmon,
      tailscale=@tailscale, andromeda=@andromeda, tailscale_ip=@tailscale_ip,
      hardware_acceleration=@hardware_acceleration, updated_at=datetime('now')
    WHERE vmid=@vmid
  `).run({ ...data, newVmid: data.vmid, vmid });
}

export function deleteInstance(vmid) {
  return db.prepare('DELETE FROM instances WHERE vmid = ?').run(vmid);
}

// ── Test helpers ──────────────────────────────────────────────────────────────

export function _resetForTest() {
  if (db) db.close();
  init(':memory:');
}

// ── Boot ──────────────────────────────────────────────────────────────────────

const DB_PATH = process.env.DB_PATH ?? DEFAULT_PATH;
try {
  init(DB_PATH);
} catch (e) {
  console.error('[catalyst] fatal: could not open database at', DB_PATH);
  console.error('[catalyst] ensure the data directory exists and is writable by the server process.');
  console.error(e);
  process.exit(1);
}