-- ============================================================================
-- Email Sequences / Drip Campaigns — Automated follow-up sequences
-- ============================================================================

CREATE TABLE IF NOT EXISTS email_campaigns (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    name VARCHAR(255) NOT NULL,
    description TEXT,
    status VARCHAR(50) NOT NULL DEFAULT 'draft',
    trigger_type VARCHAR(50) NOT NULL DEFAULT 'manual',
    trigger_config JSONB,
    created_by UUID REFERENCES users(id),
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    deleted_at TIMESTAMPTZ
);

CREATE TABLE IF NOT EXISTS email_campaign_steps (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    campaign_id UUID NOT NULL REFERENCES email_campaigns(id) ON DELETE CASCADE,
    step_order INT NOT NULL DEFAULT 0,
    delay_days INT NOT NULL DEFAULT 0,
    subject VARCHAR(500) NOT NULL,
    body_text TEXT,
    body_html TEXT,
    variables JSONB,
    created_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    updated_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
);

CREATE TABLE IF NOT EXISTS email_campaign_subscribers (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    campaign_id UUID NOT NULL REFERENCES email_campaigns(id) ON DELETE CASCADE,
    lead_id UUID REFERENCES leads(id) ON DELETE SET NULL,
    email VARCHAR(255) NOT NULL,
    contact_name VARCHAR(255),
    subscribed_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    unsubscribed_at TIMESTAMPTZ,
    status VARCHAR(50) NOT NULL DEFAULT 'pending',
    current_step INT NOT NULL DEFAULT 0,
    last_sent_at TIMESTAMPTZ,
    CONSTRAINT uq_campaign_lead UNIQUE (campaign_id, lead_id)
);

CREATE TABLE IF NOT EXISTS email_campaign_logs (
    id UUID PRIMARY KEY DEFAULT uuid_generate_v4(),
    campaign_id UUID REFERENCES email_campaigns(id) ON DELETE CASCADE,
    subscriber_id UUID REFERENCES email_campaign_subscribers(id) ON DELETE CASCADE,
    step_id UUID REFERENCES email_campaign_steps(id) ON DELETE SET NULL,
    recipient VARCHAR(255) NOT NULL,
    subject VARCHAR(500),
    body_text TEXT,
    sent_at TIMESTAMPTZ NOT NULL DEFAULT NOW(),
    status VARCHAR(50) NOT NULL DEFAULT 'sent',
    error_message TEXT
);

ALTER TABLE email_campaign_subscribers ADD CONSTRAINT IF NOT EXISTS uq_campaign_lead UNIQUE (campaign_id, lead_id);

CREATE INDEX idx_campaign_steps_order ON email_campaign_steps(campaign_id, step_order);
CREATE INDEX idx_campaign_subscribers ON email_campaign_subscribers(campaign_id, status);
CREATE INDEX idx_campaign_logs ON email_campaign_logs(campaign_id, sent_at);