package database

import (
	"context"
	"fmt"
)

// migrateEmail creates email template tables, settings, and indexes (Phase 8).
func migrateEmail(db *DB) error {
	ctx := context.Background()

	migrations := []string{
		// =============================================
		// Phase 8: E-Mail Templates (Transactional)
		// =============================================

		// Email templates (like legal_documents)
		`CREATE TABLE IF NOT EXISTS email_templates (
			id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
			type VARCHAR(50) UNIQUE NOT NULL,
			name VARCHAR(255) NOT NULL,
			description TEXT,
			is_active BOOLEAN DEFAULT TRUE,
			sort_order INT DEFAULT 0,
			created_at TIMESTAMPTZ DEFAULT NOW(),
			updated_at TIMESTAMPTZ DEFAULT NOW()
		)`,

		// Email template versions (like document_versions)
		`CREATE TABLE IF NOT EXISTS email_template_versions (
			id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
			template_id UUID REFERENCES email_templates(id) ON DELETE CASCADE,
			version VARCHAR(20) NOT NULL,
			language VARCHAR(5) DEFAULT 'de',
			subject VARCHAR(500) NOT NULL,
			body_html TEXT NOT NULL,
			body_text TEXT NOT NULL,
			summary TEXT,
			status VARCHAR(20) DEFAULT 'draft',
			published_at TIMESTAMPTZ,
			scheduled_publish_at TIMESTAMPTZ,
			created_by UUID REFERENCES users(id),
			approved_by UUID REFERENCES users(id),
			approved_at TIMESTAMPTZ,
			created_at TIMESTAMPTZ DEFAULT NOW(),
			updated_at TIMESTAMPTZ DEFAULT NOW(),
			UNIQUE(template_id, version, language)
		)`,

		// Email template approvals (like version_approvals)
		`CREATE TABLE IF NOT EXISTS email_template_approvals (
			id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
			version_id UUID REFERENCES email_template_versions(id) ON DELETE CASCADE,
			approver_id UUID REFERENCES users(id),
			action VARCHAR(30) NOT NULL,
			comment TEXT,
			created_at TIMESTAMPTZ DEFAULT NOW()
		)`,

		// Email send logs for audit
		`CREATE TABLE IF NOT EXISTS email_send_logs (
			id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
			user_id UUID REFERENCES users(id) ON DELETE SET NULL,
			version_id UUID REFERENCES email_template_versions(id) ON DELETE SET NULL,
			recipient VARCHAR(255) NOT NULL,
			subject VARCHAR(500) NOT NULL,
			status VARCHAR(20) DEFAULT 'queued',
			error_msg TEXT,
			variables JSONB,
			sent_at TIMESTAMPTZ,
			delivered_at TIMESTAMPTZ,
			created_at TIMESTAMPTZ DEFAULT NOW()
		)`,

		// Global email settings (logo, colors, signature)
		`CREATE TABLE IF NOT EXISTS email_template_settings (
			id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
			logo_url TEXT,
			logo_base64 TEXT,
			company_name VARCHAR(255) DEFAULT 'BreakPilot',
			sender_name VARCHAR(255) DEFAULT 'BreakPilot',
			sender_email VARCHAR(255) DEFAULT 'noreply@breakpilot.app',
			reply_to_email VARCHAR(255),
			footer_html TEXT,
			footer_text TEXT,
			primary_color VARCHAR(7) DEFAULT '#2563eb',
			secondary_color VARCHAR(7) DEFAULT '#64748b',
			updated_at TIMESTAMPTZ DEFAULT NOW(),
			updated_by UUID REFERENCES users(id)
		)`,

		// Insert default email settings
		`INSERT INTO email_template_settings (id, company_name, sender_name, sender_email, primary_color, secondary_color)
		VALUES (gen_random_uuid(), 'BreakPilot', 'BreakPilot', 'noreply@breakpilot.app', '#2563eb', '#64748b')
		ON CONFLICT DO NOTHING`,

		// Phase 8 Indexes
		`CREATE INDEX IF NOT EXISTS idx_email_templates_type ON email_templates(type)`,
		`CREATE INDEX IF NOT EXISTS idx_email_template_versions_template ON email_template_versions(template_id)`,
		`CREATE INDEX IF NOT EXISTS idx_email_template_versions_status ON email_template_versions(status)`,
		`CREATE INDEX IF NOT EXISTS idx_email_template_approvals_version ON email_template_approvals(version_id)`,
		`CREATE INDEX IF NOT EXISTS idx_email_send_logs_user ON email_send_logs(user_id)`,
		`CREATE INDEX IF NOT EXISTS idx_email_send_logs_created ON email_send_logs(created_at)`,
		`CREATE INDEX IF NOT EXISTS idx_email_send_logs_status ON email_send_logs(status)`,
	}

	for _, migration := range migrations {
		if _, err := db.Pool.Exec(ctx, migration); err != nil {
			return fmt.Errorf("migrateEmail: %w", err)
		}
	}

	return nil
}