From 8f08de1753ecaee95dcdf3744ad2bd9a4f4ea414 Mon Sep 17 00:00:00 2001
From: Xavier Lau <xavier@inv.cafe>
Date: Wed, 18 Jan 2023 10:28:01 +0800
Subject: [PATCH] Burn parachain backing RING (#218)

---
 tool/state-processor/src/configuration.rs | 10 ++++++++++
 tool/state-processor/src/system/README.md |  8 ++++----
 tool/state-processor/src/system/mod.rs    |  9 +++++++++
 3 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/tool/state-processor/src/configuration.rs b/tool/state-processor/src/configuration.rs
index d8438691e..4e4589a0a 100644
--- a/tool/state-processor/src/configuration.rs
+++ b/tool/state-processor/src/configuration.rs
@@ -5,22 +5,32 @@ pub const ROOT: [u8; 20] = [0x72, 0x6f, 0x6f, 0x74, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
 
 pub trait Configurable {
 	const NAME: &'static str;
+	// This account's balance will be burned.
+	// Please make sure no one transfer balance to this account.
+	const PARACHAIN_BACKING: &'static str;
 }
 impl Configurable for () {
 	const NAME: &'static str = "";
+	const PARACHAIN_BACKING: &'static str = "";
 }
 
 pub struct Darwinia;
 impl Configurable for Darwinia {
 	const NAME: &'static str = "darwinia";
+	const PARACHAIN_BACKING: &'static str =
+		"0x1000000000000000000000000000000000000000000000000000000000000000";
 }
 
 pub struct Crab;
 impl Configurable for Crab {
 	const NAME: &'static str = "crab";
+	const PARACHAIN_BACKING: &'static str =
+		"0x64766d3a0000000000000035a314e53e2fddfeca7b743042aacfb1abaf0adea3";
 }
 
 pub struct Pangolin;
 impl Configurable for Pangolin {
 	const NAME: &'static str = "pangolin";
+	const PARACHAIN_BACKING: &'static str =
+		"0x64766d3a000000000000008c585f9791ee5b4b23fe82888ce576dbb69607ebe9";
 }
diff --git a/tool/state-processor/src/system/README.md b/tool/state-processor/src/system/README.md
index 8eb034bde..868188c05 100644
--- a/tool/state-processor/src/system/README.md
+++ b/tool/state-processor/src/system/README.md
@@ -14,11 +14,12 @@
 - use all previous data to build the new accounts and calculate total issuances
   - merge solo and para account infos
     - how to deal with the account references? - TODO
+  - burn parachain backing ring
 - set `Balances::TotalIssuance`
   - compare the calculated one with the storage one
-  - remove para backing account - TODO
-  - check remaining sum - TODO
-  - XCM relate - TODO
+  - remove para backing account
+  - check remaining sum
+  - XCM related things
 - create KTON asset details
 - set accounts
   - if is EVM address
@@ -30,7 +31,6 @@
     - insert to `AccountMigration::Accounts`
 - set KTON total issuances
   - compare the calculated one with the storage one
-  - check remaining sum - TODO
 
 - some remaining accounts, bridge endpoint accounts - TODO
 - special accounts - TODO
diff --git a/tool/state-processor/src/system/mod.rs b/tool/state-processor/src/system/mod.rs
index 2b2fa4296..8d20f1d99 100644
--- a/tool/state-processor/src/system/mod.rs
+++ b/tool/state-processor/src/system/mod.rs
@@ -86,6 +86,14 @@ where
 			ring_total_issuance += v.data.reserved;
 		});
 
+		log::info!("burn parachain backing ring");
+		if let Some(a) = accounts.get_mut(&blake2_128_concat_to_string(
+			array_bytes::hex2array_unchecked::<_, 32>(S::PARACHAIN_BACKING),
+		)) {
+			ring_total_issuance -= a.ring;
+			a.ring = 0;
+		}
+
 		log::info!("`ring_total_issuance({ring_total_issuance})`");
 		log::info!("`ring_total_issuance_storage({ring_total_issuance_storage})`");
 
@@ -226,6 +234,7 @@ where
 				);
 			}
 		});
+
 		log::info!("total_remaining_ring({total_remaining_ring})");
 		log::info!("total_remaining_kton({total_remaining_kton})");