-- Migration 004: Opret contacts og customer relationships tabeller
-- Dato: 6. december 2025

-- Contacts tabel
CREATE TABLE IF NOT EXISTS contacts (
    id SERIAL PRIMARY KEY,
    first_name VARCHAR(100) NOT NULL,
    last_name VARCHAR(100) NOT NULL,
    email VARCHAR(255),
    phone VARCHAR(50),
    mobile VARCHAR(50),
    title VARCHAR(100),
    department VARCHAR(100),
    is_active BOOLEAN DEFAULT TRUE,
    vtiger_id VARCHAR(50) UNIQUE,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

-- Junction tabel for mange-til-mange relation mellem contacts og customers
CREATE TABLE IF NOT EXISTS contact_companies (
    id SERIAL PRIMARY KEY,
    contact_id INTEGER NOT NULL REFERENCES contacts(id) ON DELETE CASCADE,
    customer_id INTEGER NOT NULL REFERENCES customers(id) ON DELETE CASCADE,
    is_primary BOOLEAN DEFAULT FALSE,
    role VARCHAR(100),
    notes TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    UNIQUE(contact_id, customer_id)
);

-- Customer relationships tabel (for parent/child og billing strukturer)
CREATE TABLE IF NOT EXISTS customer_relationships (
    id SERIAL PRIMARY KEY,
    parent_customer_id INTEGER NOT NULL REFERENCES customers(id) ON DELETE CASCADE,
    child_customer_id INTEGER NOT NULL REFERENCES customers(id) ON DELETE CASCADE,
    relationship_type VARCHAR(50) NOT NULL CHECK (relationship_type IN ('parent_child', 'billing', 'partnership', 'subsidiary')),
    notes TEXT,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    UNIQUE(parent_customer_id, child_customer_id, relationship_type)
);

-- Indexes for contacts
CREATE INDEX IF NOT EXISTS idx_contacts_email ON contacts(email);
CREATE INDEX IF NOT EXISTS idx_contacts_active ON contacts(is_active);
CREATE INDEX IF NOT EXISTS idx_contacts_vtiger ON contacts(vtiger_id);
CREATE INDEX IF NOT EXISTS idx_contacts_name ON contacts(first_name, last_name);

-- Indexes for contact_companies
CREATE INDEX IF NOT EXISTS idx_contact_companies_contact ON contact_companies(contact_id);
CREATE INDEX IF NOT EXISTS idx_contact_companies_customer ON contact_companies(customer_id);
CREATE INDEX IF NOT EXISTS idx_contact_companies_primary ON contact_companies(customer_id, is_primary);

-- Indexes for customer_relationships
CREATE INDEX IF NOT EXISTS idx_customer_relationships_parent ON customer_relationships(parent_customer_id);
CREATE INDEX IF NOT EXISTS idx_customer_relationships_child ON customer_relationships(child_customer_id);
CREATE INDEX IF NOT EXISTS idx_customer_relationships_type ON customer_relationships(relationship_type);

-- Triggers for updated_at
DROP TRIGGER IF EXISTS update_contacts_updated_at ON contacts;
CREATE TRIGGER update_contacts_updated_at
    BEFORE UPDATE ON contacts
    FOR EACH ROW
    EXECUTE FUNCTION update_updated_at_column();

DROP TRIGGER IF EXISTS update_customer_relationships_updated_at ON customer_relationships;
CREATE TRIGGER update_customer_relationships_updated_at
    BEFORE UPDATE ON customer_relationships
    FOR EACH ROW
    EXECUTE FUNCTION update_updated_at_column();

-- Kommentarer
COMMENT ON TABLE contacts IS 'Contact persons associated with one or more customers';
COMMENT ON TABLE contact_companies IS 'Many-to-many junction table linking contacts to customers';
COMMENT ON TABLE customer_relationships IS 'Hierarchical and billing relationships between customers';
COMMENT ON COLUMN contact_companies.is_primary IS 'Whether this is the primary contact for this customer';
COMMENT ON COLUMN customer_relationships.relationship_type IS 'Type of relationship: parent_child, billing, partnership, subsidiary';