generate qr code svg (#2815)

* generate qr code svg prototype

* qr code for groups
fix formatting

* - letter avatar in qrcode
- escape xml in userinput (display/groupname)
- fix "Me" display name
- merge import declarations

* remove dot at the end of VerifyContactQRDescription

* if addr == displayname, show only one of them

Especially useful for yggmail accounts without usernames,
because the text would overflow otherwise.

* use real clipPath for rounded avatar

* - center avatar text better (dominant-baseline)
- add "sans-serif" to font fallback for text if arial is missing

* make corner always blue

* add [logo + "get.delta.chat"] footer to qrcode

* Update deltachat-ffi/deltachat.h

Co-authored-by: bjoern <r10s@b44t.com>

* Apply suggestions from code review

Co-authored-by: bjoern <r10s@b44t.com>

* new card design
- add stockstrings
- update changelog

* make qrcode pixels also #f2f2f2 instead of full white

* rename VERIFY_CONTACT_QR_DESC to SETUP_CONTACT
make footer text a tiny bit darker upon r10s's request

* avoid using  which is a doxygen command

* point out that one will join a group (this is still shorted and was also suggested in recent chats)

* add option to generate qr-code-svg to repl tool

* use same font-family in text and footer

* thinner card border

* remove superfluous <tspan> from footer to make color tweaking easier

* move font-weight to style, ios renderer does not pick it up from attribute; remove default font attributes not used consequently

* make get.delta.chat more visible

* align properly using dominant-baseline=central and alignment-baseline=middle, this makes things nice on all systems but android (before, ios was wrong and all others not 100% aligned as font metrics are ignored) (android needs a subsequent improvement)

Co-authored-by: bjoern <r10s@b44t.com>

src/stock_str.rs

@@ -8,7 +8,7 @@ use strum::EnumProperty;
 use strum_macros::EnumProperty;
 
 use crate::blob::BlobObject;
-use crate::chat::{self, ChatId, ProtectionStatus};
+use crate::chat::{self, Chat, ChatId, ProtectionStatus};
 use crate::config::Config;
 use crate::constants::{Viewtype, DC_CONTACT_ID_SELF};
 use crate::contact::{Contact, Origin};
@@ -330,6 +330,12 @@ pub enum StockMessage {
 
     #[strum(props(fallback = "%1$s replied, waiting for being added to the group…"))]
     SecureJoinReplies = 118,
+
+    #[strum(props(fallback = "Scan to chat with %1$s"))]
+    SetupContactQRDescription = 119,
+
+    #[strum(props(fallback = "Scan to join group %1$s"))]
+    SecureJoinGroupQRDescription = 120,
 }
 
 impl StockMessage {
@@ -614,6 +620,29 @@ pub(crate) async fn secure_join_replies(context: &Context, contact_id: u32) -> S
     }
 }
 
+/// Stock string: `Scan to chat with %1$s`.
+pub(crate) async fn setup_contact_qr_description(
+    context: &Context,
+    display_name: &str,
+    addr: &str,
+) -> String {
+    let name = if display_name == addr {
+        addr.to_owned()
+    } else {
+        format!("{} ({})", display_name, addr)
+    };
+    translated(context, StockMessage::SetupContactQRDescription)
+        .await
+        .replace1(name)
+}
+
+/// Stock string: `Scan to join %1$s`.
+pub(crate) async fn secure_join_group_qr_description(context: &Context, chat: &Chat) -> String {
+    translated(context, StockMessage::SecureJoinGroupQRDescription)
+        .await
+        .replace1(chat.get_name())
+}
+
 /// Stock string: `%1$s verified.`.
 pub(crate) async fn contact_verified(context: &Context, contact_addr: impl AsRef<str>) -> String {
     translated(context, StockMessage::ContactVerified)