-- ═══ CYPHER-HR Database Schema ═══
-- Run: psql -U KENCYPHER -d "cypher-hr" -f schema.sql

CREATE TABLE IF NOT EXISTS company_profile (
  id SERIAL PRIMARY KEY,
  company_name VARCHAR(255) NOT NULL,
  address TEXT,
  phone VARCHAR(30),
  email VARCHAR(255),
  website VARCHAR(255),
  industry VARCHAR(100),
  established_date DATE,
  created_at TIMESTAMP DEFAULT NOW(),
  updated_at TIMESTAMP DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS users (
  id SERIAL PRIMARY KEY,
  email VARCHAR(255) UNIQUE NOT NULL,
  password VARCHAR(255) NOT NULL,
  first_name VARCHAR(100) NOT NULL,
  last_name VARCHAR(100) NOT NULL,
  role VARCHAR(20) NOT NULL DEFAULT 'employee',
  department VARCHAR(100),
  position VARCHAR(100),
  phone VARCHAR(30),
  avatar_color VARCHAR(10) DEFAULT '#6366f1',
  is_active BOOLEAN DEFAULT true,
  created_at TIMESTAMP DEFAULT NOW(),
  updated_at TIMESTAMP DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS leave_policies (
  id SERIAL PRIMARY KEY,
  leave_type VARCHAR(60) NOT NULL UNIQUE,
  monthly_limit INTEGER NOT NULL DEFAULT 1,
  is_enabled BOOLEAN DEFAULT true,
  description TEXT,
  created_at TIMESTAMP DEFAULT NOW(),
  updated_at TIMESTAMP DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS leave_balances (
  id SERIAL PRIMARY KEY,
  user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  leave_policy_id INTEGER NOT NULL REFERENCES leave_policies(id) ON DELETE CASCADE,
  balance INTEGER NOT NULL DEFAULT 0,
  month INTEGER NOT NULL,
  year INTEGER NOT NULL,
  created_at TIMESTAMP DEFAULT NOW(),
  updated_at TIMESTAMP DEFAULT NOW(),
  UNIQUE(user_id, leave_policy_id, month, year)
);

CREATE TABLE IF NOT EXISTS leave_requests (
  id SERIAL PRIMARY KEY,
  user_id INTEGER NOT NULL REFERENCES users(id) ON DELETE CASCADE,
  leave_policy_id INTEGER NOT NULL REFERENCES leave_policies(id) ON DELETE CASCADE,
  start_date DATE NOT NULL,
  end_date DATE NOT NULL,
  reason TEXT,
  status VARCHAR(20) NOT NULL DEFAULT 'pending',
  admin_remarks TEXT,
  approved_by INTEGER REFERENCES users(id),
  created_at TIMESTAMP DEFAULT NOW(),
  updated_at TIMESTAMP DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_leave_balances_user ON leave_balances(user_id);
CREATE INDEX IF NOT EXISTS idx_leave_balances_period ON leave_balances(month, year);
CREATE INDEX IF NOT EXISTS idx_leave_requests_user ON leave_requests(user_id);
CREATE INDEX IF NOT EXISTS idx_leave_requests_status ON leave_requests(status);
CREATE INDEX IF NOT EXISTS idx_users_role ON users(role);
CREATE INDEX IF NOT EXISTS idx_users_email ON users(email);