-- v2.1_suppliers.sql
-- Mejora #3: Proveedores y Órdenes de Compra
--
-- Adds supplier management and purchase order workflow to tenant databases.
--
-- Workflow:
--   1. Create supplier (suppliers table)
--   2. Create PO with items (purchase_orders + purchase_order_items)
--   3. Send PO to supplier (status = 'sent')
--   4. Receive partial or full delivery (status = 'partial' | 'received')
--      → On receive: update stock via inventory_engine.record_purchase()
--      → On receive: create accounting entry via record_purchase_entry()

-- ═══════════════════════════════════════════════════════════════════════════
-- SUPPLIERS
-- ═══════════════════════════════════════════════════════════════════════════
CREATE TABLE IF NOT EXISTS suppliers (
    id SERIAL PRIMARY KEY,
    name VARCHAR(200) NOT NULL,
    contact_name VARCHAR(200),
    phone VARCHAR(50),
    email VARCHAR(200),
    rfc VARCHAR(13),
    address TEXT,
    payment_terms VARCHAR(100),  -- e.g., "30 dias", "contado"
    notes TEXT,
    is_active BOOLEAN DEFAULT true,
    created_at TIMESTAMPTZ DEFAULT NOW(),
    updated_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_suppliers_active ON suppliers(is_active);
CREATE INDEX IF NOT EXISTS idx_suppliers_name ON suppliers(name);

-- ═══════════════════════════════════════════════════════════════════════════
-- PURCHASE ORDERS
-- ═══════════════════════════════════════════════════════════════════════════
CREATE TABLE IF NOT EXISTS purchase_orders (
    id SERIAL PRIMARY KEY,
    supplier_id INTEGER REFERENCES suppliers(id) ON DELETE SET NULL,
    branch_id INTEGER REFERENCES branches(id),
    employee_id INTEGER REFERENCES employees(id),
    status VARCHAR(20) DEFAULT 'draft' NOT NULL,  -- draft, sent, partial, received, cancelled
    subtotal NUMERIC(12,2) DEFAULT 0 NOT NULL,
    tax_total NUMERIC(12,2) DEFAULT 0 NOT NULL,
    total NUMERIC(12,2) DEFAULT 0 NOT NULL,
    currency VARCHAR(3) DEFAULT 'MXN',
    exchange_rate NUMERIC(12,6) DEFAULT 1.0,
    notes TEXT,
    supplier_invoice VARCHAR(100),
    expected_date DATE,
    sent_at TIMESTAMPTZ,
    received_at TIMESTAMPTZ,
    cancelled_at TIMESTAMPTZ,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_po_supplier ON purchase_orders(supplier_id);
CREATE INDEX IF NOT EXISTS idx_po_status ON purchase_orders(status);
CREATE INDEX IF NOT EXISTS idx_po_branch ON purchase_orders(branch_id);
CREATE INDEX IF NOT EXISTS idx_po_created ON purchase_orders(created_at DESC);

-- ═══════════════════════════════════════════════════════════════════════════
-- PURCHASE ORDER ITEMS
-- ═══════════════════════════════════════════════════════════════════════════
CREATE TABLE IF NOT EXISTS purchase_order_items (
    id SERIAL PRIMARY KEY,
    po_id INTEGER NOT NULL REFERENCES purchase_orders(id) ON DELETE CASCADE,
    inventory_id INTEGER REFERENCES inventory(id) ON DELETE SET NULL,
    part_number VARCHAR(100),
    name VARCHAR(300),
    quantity INTEGER NOT NULL DEFAULT 1,
    received_qty INTEGER DEFAULT 0,
    unit_price NUMERIC(12,2) NOT NULL DEFAULT 0,
    subtotal NUMERIC(12,2) NOT NULL DEFAULT 0,
    notes TEXT,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_poi_po ON purchase_order_items(po_id);
CREATE INDEX IF NOT EXISTS idx_poi_inventory ON purchase_order_items(inventory_id);