use crate::{
    authentication::{self, AuthenticatedUser, Credentials, validate_credentials},
    routes::{AdminError, AppError},
    startup::AppState,
    templates::MessageTemplate,
};
use askama::Template;
use axum::{
    Extension, Form,
    extract::State,
    response::{Html, IntoResponse, Response},
};
use secrecy::{ExposeSecret, SecretString};

#[derive(serde::Deserialize)]
pub struct PasswordFormData {
    pub current_password: SecretString,
    pub new_password: SecretString,
    pub new_password_check: SecretString,
}

pub async fn change_password(
    Extension(AuthenticatedUser { user_id, username }): Extension<AuthenticatedUser>,
    State(AppState {
        connection_pool, ..
    }): State<AppState>,
    Form(form): Form<PasswordFormData>,
) -> Result<Response, AppError> {
    let credentials = Credentials {
        username,
        password: form.current_password,
    };
    if form.new_password.expose_secret() != form.new_password_check.expose_secret() {
        Err(AdminError::ChangePassword(
            "You entered two different passwords - the field values must match.".to_string(),
        )
        .into())
    } else if validate_credentials(credentials, &connection_pool)
        .await
        .is_err()
    {
        Err(AdminError::ChangePassword("The current password is incorrect.".to_string()).into())
    } else if let Err(e) = verify_password(form.new_password.expose_secret()) {
        Err(AdminError::ChangePassword(e).into())
    } else {
        authentication::change_password(user_id, form.new_password, &connection_pool)
            .await
            .map_err(|e| AdminError::ChangePassword(e.to_string()))?;
        let template = MessageTemplate::Success {
            message: "Your password has been changed.".to_string(),
        };
        Ok(Html(template.render().unwrap()).into_response())
    }
}

fn verify_password(password: &str) -> Result<(), String> {
    if password.len() < 12 || password.len() > 128 {
        return Err("The password must contain between 12 and 128 characters.".into());
    }
    Ok(())
}