Validate and simplify LoginParam struct

This makes sure that under normal circumstances the LoginParam struct
is always fully validated, ensure future use does not have to be
careful with this.

The brittle handling of `server_flags` is also abstraced away from
users of it and is now handled entirely internally, as the flags is
really only a boolean a lot of the flag parsing complexity is removed.
The OAuth2 flag is moved into the ServerLoginParam struct as it really
belongs in there.

src/configure.rs

@@ -11,7 +11,6 @@ use async_std::task;
 use percent_encoding::{utf8_percent_encode, NON_ALPHANUMERIC};
 
 use crate::config::Config;
-use crate::constants::{DC_LP_AUTH_FLAGS, DC_LP_AUTH_NORMAL, DC_LP_AUTH_OAUTH2};
 use crate::context::Context;
 use crate::dc_tools::{time, EmailAddress};
 use crate::imap::Imap;
@@ -145,28 +144,6 @@ impl Context {
 async fn configure(ctx: &Context, param: &mut LoginParam) -> Result<()> {
     progress!(ctx, 1);
 
-    // Check basic settings.
-    ensure!(!param.addr.is_empty(), "Please enter an email address.");
-
-    // Only check for IMAP password, SMTP password is an "advanced" setting.
-    ensure!(!param.imap.password.is_empty(), "Please enter a password.");
-    if param.smtp.password.is_empty() {
-        param.smtp.password = param.imap.password.clone()
-    }
-
-    // Normalize authentication flags.
-    let oauth2 = match param.server_flags & DC_LP_AUTH_FLAGS as i32 {
-        DC_LP_AUTH_OAUTH2 => true,
-        DC_LP_AUTH_NORMAL => false,
-        _ => false,
-    };
-    param.server_flags &= !(DC_LP_AUTH_FLAGS as i32);
-    param.server_flags |= if oauth2 {
-        DC_LP_AUTH_OAUTH2 as i32
-    } else {
-        DC_LP_AUTH_NORMAL as i32
-    };
-
     let socks5_config = param.socks5_config.clone();
     let socks5_enabled = socks5_config.is_some();
 
@@ -176,8 +153,9 @@ async fn configure(ctx: &Context, param: &mut LoginParam) -> Result<()> {
     // Step 1: Load the parameters and check email-address and password
 
     // Do oauth2 only if socks5 is disabled. As soon as we have a http library that can do
-    // socks5 requests, this can work with socks5 too
-    if oauth2 && !socks5_enabled {
+    // socks5 requests, this can work with socks5 too.  OAuth is always set either for both
+    // IMAP and SMTP or not at all.
+    if param.imap.oauth2 && !socks5_enabled {
         // the used oauth2 addr may differ, check this.
         // if dc_get_oauth2_addr() is not available in the oauth2 implementation, just use the given one.
         progress!(ctx, 10);
@@ -358,7 +336,6 @@ async fn configure(ctx: &Context, param: &mut LoginParam) -> Result<()> {
                 &smtp_param,
                 &socks5_config,
                 &smtp_addr,
-                oauth2,
                 provider_strict_tls,
                 &mut smtp,
             )
@@ -406,7 +383,6 @@ async fn configure(ctx: &Context, param: &mut LoginParam) -> Result<()> {
             &param.imap,
             &param.socks5_config,
             &param.addr,
-            oauth2,
             provider_strict_tls,
         )
         .await
@@ -562,26 +538,22 @@ async fn try_imap_one_param(
     param: &ServerLoginParam,
     socks5_config: &Option<Socks5Config>,
     addr: &str,
-    oauth2: bool,
     provider_strict_tls: bool,
 ) -> Result<Imap, ConfigurationError> {
     let inf = format!(
         "imap: {}@{}:{} security={} certificate_checks={} oauth2={}",
-        param.user, param.server, param.port, param.security, param.certificate_checks, oauth2
+        param.user,
+        param.server,
+        param.port,
+        param.security,
+        param.certificate_checks,
+        param.oauth2
     );
     info!(context, "Trying: {}", inf);
 
     let (_s, r) = async_std::channel::bounded(1);
 
-    let mut imap = match Imap::new(
-        param,
-        socks5_config.clone(),
-        addr,
-        oauth2,
-        provider_strict_tls,
-        r,
-    )
-    .await
+    let mut imap = match Imap::new(param, socks5_config.clone(), addr, provider_strict_tls, r).await
     {
         Err(err) => {
             info!(context, "failure: {}", err);
@@ -613,7 +585,6 @@ async fn try_smtp_one_param(
     param: &ServerLoginParam,
     socks5_config: &Option<Socks5Config>,
     addr: &str,
-    oauth2: bool,
     provider_strict_tls: bool,
     smtp: &mut Smtp,
 ) -> Result<(), ConfigurationError> {
@@ -624,7 +595,7 @@ async fn try_smtp_one_param(
         param.port,
         param.security,
         param.certificate_checks,
-        oauth2,
+        param.oauth2,
         if let Some(socks5_config) = socks5_config {
             socks5_config.to_string()
         } else {
@@ -634,14 +605,7 @@ async fn try_smtp_one_param(
     info!(context, "Trying: {}", inf);
 
     if let Err(err) = smtp
-        .connect(
-            context,
-            param,
-            socks5_config,
-            addr,
-            oauth2,
-            provider_strict_tls,
-        )
+        .connect(context, param, socks5_config, addr, provider_strict_tls)
         .await
     {
         info!(context, "failure: {}", err);