use crate::State;
use ldap3::{exop::PasswordModify, LdapConn, Mod, Scope, SearchEntry};
use std::collections::HashSet;
use tide::{
    prelude::{json, Deserialize},
    Request,
};

#[derive(Debug, Deserialize)]
pub struct LdapUpdate {
    user: String,
    pass: String,
    field: String,
    value: String,
}

/// Handles updating a single field with the users own password
pub async fn post_update_ldap(mut req: Request<State>) -> tide::Result {
    let LdapUpdate {
        user,
        pass,
        field,
        value,
    } = req.body_json().await?;

    // check that any mail is not using @skynet.ie
    if field == "mail" && value.trim().ends_with("@skynet.ie") {
        return Ok(json!({"result": "error", "error": "skynet email not valid contact address"}).into());
    }

    let config = &req.state().config;

    // easier to give each request its own connection
    let mut ldap = LdapConn::new(&config.ldap_host)?;

    let dn = format!("uid={},ou=users,dc=skynet,dc=ie", user);
    ldap.simple_bind(&dn, &pass)?.success()?;

    // always assume insecure
    let mut pw_keep_same = false;

    // get the users current password hash
    let (rs, _res) = ldap.search(&dn, Scope::Base, "(objectClass=*)", vec!["userPassword"])?.success()?;
    if !rs.is_empty() {
        let tmp = SearchEntry::construct(rs[0].clone());
        if !tmp.attrs["userPassword"].is_empty() && tmp.attrs["userPassword"][0].starts_with("{SSHA512}") {
            pw_keep_same = true;
        }
    }

    // check if the password field itself is being updated
    let (pass_old, pass_new) = if &field != "userPassword" {
        // if password is not being updated then just update the required field
        let mods = vec![
            // the value we are updating
            Mod::Replace(field, HashSet::from([value])),
        ];

        ldap.modify(&dn, mods)?.success()?;

        // pass back the "old" and "new" passwords
        // using this means we can create teh vars without them needing to be mutable
        (pass.clone(), pass.clone())
    } else {
        // password is going to be updated, even if the old value is not starting with "{SSHA512}"
        pw_keep_same = false;
        (pass.clone(), value)
    };

    // changing teh password because of an explicit request or upgrading teh security.
    if !pw_keep_same {
        // really easy to update password once ye know how
        let tmp = PasswordModify {
            // none as we are staying on the same connection
            user_id: None,
            old_pass: Some(&pass_old),
            new_pass: Some(&pass_new),
        };

        ldap.extended(tmp)?.success()?;
    };

    ldap.unbind()?;

    Ok(json!({"result": "success"}).into())
}