-- ============================================================
-- v3.5 WhatsApp State Machine
-- Reorganización del chatbot de AI libre a flujo estructurado
-- ============================================================

-- 1. Extender whatsapp_sessions con estado y contexto
-- ---------------------------------------------------
ALTER TABLE whatsapp_sessions
ADD COLUMN IF NOT EXISTS state VARCHAR(50) DEFAULT 'idle',
ADD COLUMN IF NOT EXISTS state_data JSONB DEFAULT '{}',
ADD COLUMN IF NOT EXISTS customer_id INTEGER REFERENCES customers(id),
ADD COLUMN IF NOT EXISTS branch_id INTEGER REFERENCES branches(id),
ADD COLUMN IF NOT EXISTS learning_cycle INTEGER DEFAULT 0,
ADD COLUMN IF NOT EXISTS created_at TIMESTAMPTZ DEFAULT NOW();

-- Índices para lookups rápidos de sesión
CREATE INDEX IF NOT EXISTS idx_wa_sessions_state ON whatsapp_sessions(state);
CREATE INDEX IF NOT EXISTS idx_wa_sessions_customer ON whatsapp_sessions(customer_id);
CREATE INDEX IF NOT EXISTS idx_wa_sessions_updated ON whatsapp_sessions(updated_at);

-- 2. Tabla de vínculo persistente WA ID ↔ Cliente
-- ------------------------------------------------
CREATE TABLE IF NOT EXISTS wa_customer_links (
    phone VARCHAR(50) PRIMARY KEY,
    customer_id INTEGER NOT NULL REFERENCES customers(id),
    created_at TIMESTAMPTZ DEFAULT NOW(),
    updated_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_wa_cust_link_customer ON wa_customer_links(customer_id);

-- Trigger para updated_at
CREATE OR REPLACE FUNCTION update_wa_link_timestamp()
RETURNS TRIGGER AS $$
BEGIN
    NEW.updated_at = NOW();
    RETURN NEW;
END;
$$ LANGUAGE plpgsql;

DROP TRIGGER IF EXISTS trg_wa_link_updated ON wa_customer_links;
CREATE TRIGGER trg_wa_link_updated
    BEFORE UPDATE ON wa_customer_links
    FOR EACH ROW EXECUTE FUNCTION update_wa_link_timestamp();

-- 3. Tabla de sesiones de aprendizaje (piezas no resueltas)
-- ---------------------------------------------------------
CREATE TABLE IF NOT EXISTS wa_learning_sessions (
    id SERIAL PRIMARY KEY,
    phone VARCHAR(50) NOT NULL,
    customer_id INTEGER REFERENCES customers(id),
    description TEXT NOT NULL,
    offered_parts JSONB DEFAULT '[]',
    status VARCHAR(20) DEFAULT 'pending',
    resolved_part_id INTEGER REFERENCES inventory(id),
    resolution_sale_id INTEGER REFERENCES sales(id),
    created_at TIMESTAMPTZ DEFAULT NOW(),
    resolved_at TIMESTAMPTZ
);

CREATE INDEX IF NOT EXISTS idx_wa_learn_phone ON wa_learning_sessions(phone);
CREATE INDEX IF NOT EXISTS idx_wa_learn_status ON wa_learning_sessions(status);
CREATE INDEX IF NOT EXISTS idx_wa_learn_customer ON wa_learning_sessions(customer_id);
CREATE INDEX IF NOT EXISTS idx_wa_learn_created ON wa_learning_sessions(created_at);

-- 4. Tabla de configuración de envío por sucursal
-- ------------------------------------------------
CREATE TABLE IF NOT EXISTS branch_delivery_config (
    id SERIAL PRIMARY KEY,
    branch_id INTEGER NOT NULL UNIQUE REFERENCES branches(id),
    is_enabled BOOLEAN DEFAULT FALSE,
    delivery_fee NUMERIC(12,2) DEFAULT 0,
    free_delivery_threshold NUMERIC(12,2) DEFAULT NULL,
    coverage_radius_km INTEGER DEFAULT NULL,
    delivery_hours VARCHAR(100) DEFAULT 'Lun-Vie 9:00-18:00',
    notes TEXT,
    created_at TIMESTAMPTZ DEFAULT NOW(),
    updated_at TIMESTAMPTZ DEFAULT NOW()
);

-- 5. Agregar push_name a whatsapp_messages (schema drift existente)
-- ------------------------------------------------------------------
ALTER TABLE whatsapp_messages
ADD COLUMN IF NOT EXISTS push_name VARCHAR(200);

-- 6. Migrar datos existentes: vincular por teléfono
-- --------------------------------------------------
-- Intentar vincular sesiones WA existentes con customers por teléfono
INSERT INTO wa_customer_links (phone, customer_id)
SELECT ws.phone, c.id
FROM whatsapp_sessions ws
JOIN customers c ON c.phone = ws.phone
WHERE ws.phone IS NOT NULL AND c.phone IS NOT NULL
ON CONFLICT (phone) DO NOTHING;

-- Actualizar customer_id en whatsapp_sessions desde el vínculo
UPDATE whatsapp_sessions ws
SET customer_id = wcl.customer_id
FROM wa_customer_links wcl
WHERE ws.phone = wcl.phone AND ws.customer_id IS NULL;