import crypto from "node:crypto";
import { and, asc, eq } from "drizzle-orm";
import type { AppDatabase } from "../database-context.js";
import { users } from "../schema/users.js";
import {
  LastActiveAdminStoreError,
  UsernameAlreadyExistsStoreError,
  type CreateUserAccount,
  type UserStore,
} from "../../domain/ports/user.store.js";
import type { UserRole } from "../../shared/constants/user-roles.js";

function isUniqueConstraintError(error: unknown): boolean {
  return (
    error instanceof Error &&
    "code" in error &&
    (error as { code?: unknown }).code === "SQLITE_CONSTRAINT_UNIQUE"
  );
}

export class UserRepository implements UserStore {
  constructor(private readonly database: AppDatabase) {}

  async list() {
    const db = this.database;
    return db.select().from(users).orderBy(asc(users.name));
  }

  async count() {
    const db = this.database;
    const rows = await db.select({ id: users.id }).from(users).limit(1);
    return rows.length;
  }

  async findById(userId: string): Promise<typeof users.$inferSelect | null> {
    const db = this.database;
    const [row] = await db.select().from(users).where(eq(users.id, userId)).limit(1);
    return row ?? null;
  }

  async findByUsername(username: string): Promise<typeof users.$inferSelect | null> {
    const db = this.database;
    const [row] = await db
      .select()
      .from(users)
      .where(eq(users.username, username.trim().toLowerCase()))
      .limit(1);
    return row ?? null;
  }

  async create(input: CreateUserAccount) {
    const db = this.database;
    const id = crypto.randomUUID();
    try {
      await db.insert(users).values({
        id,
        username: input.username.trim().toLowerCase(),
        name: input.name,
        role: input.role,
        passwordHash: input.passwordHash,
        active: true,
        mustChangePassword: true,
      });
    } catch (error) {
      if (isUniqueConstraintError(error)) throw new UsernameAlreadyExistsStoreError();
      throw error;
    }
    return this.findById(id);
  }

  async updateRoleAndActive(
    userId: string,
    patch: { role?: UserRole; active?: boolean }
  ) {
    return this.database.transaction((tx) => {
      const [target] = tx.select().from(users).where(eq(users.id, userId)).limit(1).all();
      if (!target) return null;

      const removesActiveAdmin =
        target.role === "admin" &&
        target.active &&
        (patch.role === "user" || patch.active === false);
      if (removesActiveAdmin) {
        const activeAdmins = tx
          .select({ id: users.id })
          .from(users)
          .where(and(eq(users.role, "admin"), eq(users.active, true)))
          .limit(2)
          .all();
        if (activeAdmins.length <= 1) throw new LastActiveAdminStoreError();
      }

      tx.update(users)
        .set({
          ...(patch.role !== undefined ? { role: patch.role } : {}),
          ...(patch.active !== undefined ? { active: patch.active } : {}),
          updatedAt: new Date(),
        })
        .where(eq(users.id, userId))
        .run();
      return tx.select().from(users).where(eq(users.id, userId)).limit(1).all()[0] ?? null;
    });
  }

  async setPassword(
    userId: string,
    passwordHash: string,
    mustChangePassword: boolean
  ) {
    const db = this.database;
    await db
      .update(users)
      .set({ passwordHash, mustChangePassword, updatedAt: new Date() })
      .where(eq(users.id, userId));
    return this.findById(userId);
  }
}