/**
 * Database client for the portal-db PostgreSQL database.
 *
 * Uses the `pg` package directly — no ORM overhead for a single table.
 * The tenant_requests table acts as the approval gate between customer
 * registration and actual PiecedTenant CR creation.
 *
 * Connection: via DATABASE_URL env var pointing to CloudNativePG cluster.
 */

import { Pool } from "pg";
import type { TenantRequest, TenantRequestStatus } from "@/types";

// Lazy-init: pool is created on first use, not at module import time.
// This avoids "Invalid URL" errors during Next.js build when env vars
// aren't available yet.
let _pool: Pool | null = null;

function getPool(): Pool {
  if (!_pool) {
    const url = process.env.DATABASE_URL;
    if (!url) throw new Error("DATABASE_URL is not set");
    _pool = new Pool({
      connectionString: url,
      max: 5,
      idleTimeoutMillis: 30_000,
    });
  }
  return _pool;
}

// ---------------------------------------------------------------------------
// Schema migration (idempotent)
// ---------------------------------------------------------------------------

const MIGRATION_SQL = `
CREATE TABLE IF NOT EXISTS tenant_requests (
  id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
  zitadel_org_id TEXT NOT NULL UNIQUE,
  zitadel_user_id TEXT NOT NULL,
  company_name TEXT NOT NULL,
  contact_name TEXT NOT NULL,
  contact_email TEXT NOT NULL,
  agent_name TEXT NOT NULL DEFAULT 'Assistant',
  soul_md TEXT,
  packages TEXT[] DEFAULT '{}',
  billing_address JSONB DEFAULT '{}',
  billing_notes TEXT,
  status TEXT NOT NULL DEFAULT 'pending',
  admin_notes TEXT,
  tenant_name TEXT,
  created_at TIMESTAMPTZ NOT NULL DEFAULT now(),
  updated_at TIMESTAMPTZ NOT NULL DEFAULT now()
);

CREATE INDEX IF NOT EXISTS idx_tenant_requests_status ON tenant_requests(status);
CREATE INDEX IF NOT EXISTS idx_tenant_requests_org_id ON tenant_requests(zitadel_org_id);
`;

let migrated = false;

export async function ensureSchema(): Promise<void> {
  if (migrated) return;
  await getPool().query(MIGRATION_SQL);
  migrated = true;
}

// ---------------------------------------------------------------------------
// CRUD
// ---------------------------------------------------------------------------

export async function createTenantRequest(
  params: Omit<TenantRequest, "id" | "status" | "createdAt" | "updatedAt">
): Promise<TenantRequest> {
  await ensureSchema();
  const result = await getPool().query<TenantRequest>(
    `INSERT INTO tenant_requests
     (zitadel_org_id, zitadel_user_id, company_name, contact_name,
      contact_email, agent_name, soul_md, packages, billing_address, billing_notes)
     VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10)
     RETURNING *`,
    [
      params.zitadelOrgId,
      params.zitadelUserId,
      params.companyName,
      params.contactName,
      params.contactEmail,
      params.agentName,
      params.soulMd,
      params.packages,
      JSON.stringify(params.billingAddress),
      params.billingNotes,
    ]
  );
  return mapRow(result.rows[0]);
}

export async function getTenantRequestByOrgId(
  orgId: string
): Promise<TenantRequest | null> {
  await ensureSchema();
  const result = await getPool().query(
    "SELECT * FROM tenant_requests WHERE zitadel_org_id = $1",
    [orgId]
  );
  return result.rows[0] ? mapRow(result.rows[0]) : null;
}

export async function getTenantRequestById(
  id: string
): Promise<TenantRequest | null> {
  await ensureSchema();
  const result = await getPool().query(
    "SELECT * FROM tenant_requests WHERE id = $1",
    [id]
  );
  return result.rows[0] ? mapRow(result.rows[0]) : null;
}

export async function listTenantRequests(
  status?: TenantRequestStatus
): Promise<TenantRequest[]> {
  await ensureSchema();
  const pool = getPool();
  const query = status
    ? { text: "SELECT * FROM tenant_requests WHERE status = $1 ORDER BY created_at DESC", values: [status] }
    : { text: "SELECT * FROM tenant_requests ORDER BY created_at DESC", values: [] };
  const result = await pool.query(query);
  return result.rows.map(mapRow);
}

export async function updateTenantRequestStatus(
  id: string,
  status: TenantRequestStatus,
  extra?: { adminNotes?: string | null; tenantName?: string; clearAdminNotes?: boolean }
): Promise<TenantRequest> {
  await ensureSchema();

  // If clearAdminNotes is true, explicitly set admin_notes to NULL
  // Otherwise use COALESCE to preserve existing value when not provided
  const adminNotesExpr = extra?.clearAdminNotes
    ? "$2"
    : "COALESCE($2, admin_notes)";

  const result = await getPool().query(
    `UPDATE tenant_requests
     SET status = $1, admin_notes = ${adminNotesExpr},
         tenant_name = COALESCE($3, tenant_name), updated_at = now()
     WHERE id = $4
     RETURNING *`,
    [status, extra?.adminNotes ?? null, extra?.tenantName ?? null, id]
  );
  if (!result.rows[0]) throw new Error(`TenantRequest ${id} not found`);
  return mapRow(result.rows[0]);
}

/**
 * Sync provisioning statuses: for all requests with status "provisioning",
 * check if the PiecedTenant CR has reached "Ready" and update to "active".
 * Called from the admin requests list endpoint.
 */
export async function syncProvisioningStatuses(
  checkTenantPhase: (tenantName: string) => Promise<string | null>
): Promise<void> {
  await ensureSchema();
  const pool = getPool();
  const result = await pool.query(
    "SELECT id, tenant_name FROM tenant_requests WHERE status = 'provisioning' AND tenant_name IS NOT NULL"
  );

  for (const row of result.rows) {
    try {
      const phase = await checkTenantPhase(row.tenant_name);
      if (phase === "Ready" || phase === "Running") {
        await pool.query(
          "UPDATE tenant_requests SET status = 'active', updated_at = now() WHERE id = $1",
          [row.id]
        );
      }
    } catch (e) {
      console.error(`Failed to sync status for request ${row.id}:`, e);
    }
  }
}

// ---------------------------------------------------------------------------
// Row mapping (snake_case → camelCase)
// ---------------------------------------------------------------------------

function mapRow(row: any): TenantRequest {
  return {
    id: row.id,
    zitadelOrgId: row.zitadel_org_id,
    zitadelUserId: row.zitadel_user_id,
    companyName: row.company_name,
    contactName: row.contact_name,
    contactEmail: row.contact_email,
    agentName: row.agent_name,
    soulMd: row.soul_md,
    packages: row.packages ?? [],
    billingAddress: typeof row.billing_address === "string"
      ? JSON.parse(row.billing_address)
      : row.billing_address ?? {},
    billingNotes: row.billing_notes,
    status: row.status as TenantRequestStatus,
    adminNotes: row.admin_notes,
    tenantName: row.tenant_name,
    createdAt: row.created_at?.toISOString?.() ?? row.created_at,
    updatedAt: row.updated_at?.toISOString?.() ?? row.updated_at,
  };
}