import { z } from 'zod';

/**
 * Auth-related schemas shared between api (runtime validation) and web
 * (form validation). Field error messages are i18n keys resolved by the
 * client; the api returns them inside ApiErrorBody.details.
 */

export const usernameSchema = z
  .string()
  .min(3, 'validation.username.tooShort')
  .max(32, 'validation.username.tooLong')
  .regex(/^[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$/i, 'validation.username.charset');

/**
 * Password policy per issue #13: length over composition rules, plus a
 * small blocklist of the most common passwords (full breach-list checks
 * are deliberately out of scope for v1).
 */
const COMMON_PASSWORDS = new Set([
  '1234567890',
  'qwertyuiop',
  'password12',
  'password123',
  'passwort123',
  '1q2w3e4r5t',
  'iloveyou12',
  'sonnenschein',
  'schalke04!',
  'aaaaaaaaaa',
  '1234567890a',
  'qwertz1234',
]);

export const passwordSchema = z
  .string()
  .min(10, 'validation.password.tooShort')
  .max(128, 'validation.password.tooLong')
  .refine((value) => !COMMON_PASSWORDS.has(value.toLowerCase()), 'validation.password.tooCommon');

export const signupInputSchema = z.object({
  username: usernameSchema,
  email: z.string().email('validation.email.invalid').max(254),
  displayName: z.string().trim().min(1, 'validation.displayName.required').max(80),
  password: passwordSchema,
  locale: z.enum(['de', 'en']).default('en'),
  /** Invitation token (issue #332): lets this one signup through even
   * while registration is closed. */
  invitationToken: z.string().min(16).max(256).optional(),
});
export type SignupInput = z.infer<typeof signupInputSchema>;
/** Form-side type: locale is optional before Zod applies its default. */
export type SignupFormInput = z.input<typeof signupInputSchema>;

export const loginInputSchema = z.object({
  usernameOrEmail: z.string().min(1, 'validation.required'),
  password: z.string().min(1, 'validation.required'),
});
export type LoginInput = z.infer<typeof loginInputSchema>;

export const verifyEmailInputSchema = z.object({ token: z.string().min(16).max(256) });
export const resendVerificationInputSchema = z.object({
  email: z.string().email('validation.email.invalid'),
});
export const forgotPasswordInputSchema = z.object({
  email: z.string().email('validation.email.invalid'),
});
export const resetPasswordInputSchema = z.object({
  token: z.string().min(16).max(256),
  password: passwordSchema,
});
/** Form-side schema for the reset page (token travels via URL, not form). */
export const resetPasswordFormSchema = z.object({ password: passwordSchema });
export const updateProfileInputSchema = z.object({
  displayName: z.string().trim().min(1, 'validation.displayName.required').max(80).optional(),
  locale: z.enum(['de', 'en']).optional(),
  /** Auto-watch preferences (issue #93). */
  autoWatchOwnPages: z.boolean().optional(),
  autoWatchOnComment: z.boolean().optional(),
  /** E-mail digest cadence (issue #95). */
  digestFrequency: z.enum(['hourly', 'daily', 'off']).optional(),
});
export const changePasswordInputSchema = z.object({
  currentPassword: z.string().min(1, 'validation.required'),
  newPassword: passwordSchema,
});

/**
 * What the login screen may offer (issue #214, ADR 0021): the local
 * password form and/or the deploy-configured OIDC provider. `local` becomes
 * switchable with #216 (`AUTH_LOCAL_ENABLED`).
 */
export interface AuthMethodsView {
  local: boolean;
  oidc: { label: string } | null;
}

/** Public shape of the signed-in user, returned by /auth/me. */
export interface CurrentUser {
  id: string;
  username: string;
  email: string;
  displayName: string;
  locale: 'de' | 'en';
  isSiteAdmin: boolean;
  autoWatchOwnPages: boolean;
  autoWatchOnComment: boolean;
  digestFrequency: 'hourly' | 'daily' | 'off';
}