feat(pop-api): further implementation of nfts api (#21)

* fix: restore missing ink contract attribute

* feat(pop-api): further implementation of nfts api

* feat(pop-api): add support to query nft state in extension

* feat(pop-api): continue support for nft state queries

* fix: add missing import

* fix: increase visibility

* fix: add missing derives

* feat(pop-api): add relay_chain_block_number function

* refactor(nfts): group functions as per pallet

* chore: address clippy warnings

---------

Co-authored-by: Peter White <petras9789@gmail.com>

contracts/pop-api-examples/nfts/lib.rs

@@ -5,63 +5,80 @@ use pop_api::nfts;
 #[derive(Debug, Copy, Clone, PartialEq, Eq, scale::Encode, scale::Decode)]
 #[cfg_attr(feature = "std", derive(scale_info::TypeInfo))]
 pub enum ContractError {
-    NftsError(nfts::Error),
+	InvalidCollection,
+	ItemAlreadyExists,
+	NftsError(nfts::Error),
+	NotOwner,
 }
 
 impl From<nfts::Error> for ContractError {
-    fn from(value: nfts::Error) -> Self {
-        ContractError::NftsError(value)
-    }
+	fn from(value: nfts::Error) -> Self {
+		ContractError::NftsError(value)
+	}
 }
 
 #[ink::contract(env = pop_api::Environment)]
 mod pop_api_extension_demo {
-    use super::ContractError;
+	use super::ContractError;
 
-    #[ink(storage)]
-    #[derive(Default)]
-    pub struct PopApiExtensionDemo;
+	#[ink(storage)]
+	#[derive(Default)]
+	pub struct PopApiExtensionDemo;
 
-    impl PopApiExtensionDemo {
-        #[ink(constructor, payable)]
-        pub fn new() -> Self {
-            ink::env::debug_println!("PopApiExtensionDemo::new");
-            Default::default()
-        }
+	impl PopApiExtensionDemo {
+		#[ink(constructor, payable)]
+		pub fn new() -> Self {
+			ink::env::debug_println!("Contract::new");
+			Default::default()
+		}
 
-        #[ink(message)]
-        pub fn mint_through_runtime(
-            &mut self,
-            collection_id: u32,
-            item_id: u32,
-            receiver: AccountId,
-        ) -> Result<(), ContractError> {
-            ink::env::debug_println!("PopApiExtensionDemo::mint_through_runtime: collection_id: {:?} \nitem_id {:?} \nreceiver: {:?}, ", collection_id, item_id, receiver);
+		#[ink(message)]
+		pub fn mint_through_runtime(
+			&mut self,
+			collection_id: u32,
+			item_id: u32,
+			receiver: AccountId,
+		) -> Result<(), ContractError> {
+			ink::env::debug_println!(
+				"Contract::mint_through_runtime: collection_id: {:?} item_id {:?} receiver: {:?}",
+				collection_id,
+				item_id,
+				receiver
+			);
 
-            // simplified API call
-            let result = pop_api::nfts::mint(collection_id, item_id, receiver);
-            ink::env::debug_println!(
-                "PopApiExtensionDemo::mint_through_runtime result: {result:?}"
-            );
-            if let Err(pop_api::nfts::Error::NoConfig) = result {
-                ink::env::debug_println!(
-                    "PopApiExtensionDemo::mint_through_runtime expected error received"
-                );
-            }
-            result?;
+			// Check if item already exists (demo purposes only, unnecessary as would expect check in mint call)
+			if pop_api::nfts::item(collection_id, item_id)?.is_some() {
+				return Err(ContractError::ItemAlreadyExists);
+			}
 
-            ink::env::debug_println!("PopApiExtensionDemo::mint_through_runtime end");
-            Ok(())
-        }
-    }
+			// mint api
+			pop_api::nfts::mint(collection_id, item_id, receiver)?;
+			ink::env::debug_println!("Contract::mint_through_runtime: item minted successfully");
 
-    #[cfg(test)]
-    mod tests {
-        use super::*;
+			// check owner
+			match pop_api::nfts::owner(collection_id, item_id)? {
+				Some(owner) if owner == receiver => {
+					ink::env::debug_println!(
+						"Contract::mint_through_runtime success: minted item belongs to receiver"
+					);
+				},
+				_ => {
+					return Err(ContractError::NotOwner);
+				},
+			}
 
-        #[ink::test]
-        fn default_works() {
-            PopApiExtensionDemo::new();
-        }
-    }
+			ink::env::debug_println!("Contract::mint_through_runtime end");
+			Ok(())
+		}
+	}
+
+	#[cfg(test)]
+	mod tests {
+		use super::*;
+
+		#[ink::test]
+		fn default_works() {
+			PopApiExtensionDemo::new();
+		}
+	}
 }

pop-api/Cargo.toml

@@ -6,9 +6,10 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
+enumflags2 = { version = "0.7.7" }
 ink = { version = "4.3.0", default-features = false }
 scale = { package = "parity-scale-codec", version = "3", default-features = false, features = ["derive"] }
-scale-info = { version = "2.6", default-features = false, features = ["derive"], optional = true }
+scale-info = { version = "2.6", default-features = false, features = ["derive"] }
 sp-io = { version = "23.0.0", default-features = false, features = ["disable_panic_handler", "disable_oom", "disable_allocator"] }
 sp-runtime = { version = "24.0", default-features = false }
 
@@ -22,6 +23,7 @@ crate-type = ["rlib"]
 [features]
 default = ["std"]
 std = [
+    "enumflags2/std",
     "ink/std",
     "pop-api-primitives/std",
     "scale/std",

pop-api/primitives/Cargo.toml

@@ -6,6 +6,7 @@ version = "0.0.0"
 edition = "2021"
 
 [dependencies]
+bounded-collections = { version = "0.1", default-features = false }
 scale = { package = "parity-scale-codec", version = "3", default-features = false, features = ["derive"] }
 scale-info = { version = "2.6", default-features = false, features = ["derive"], optional = true }
 
@@ -17,6 +18,7 @@ crate-type = ["rlib"]
 [features]
 default = ["std"]
 std = [
+    "bounded-collections/std",
     "scale/std",
     "scale-info/std",
 ]

pop-api/primitives/src/lib.rs

@@ -1,3 +1,18 @@
 #![cfg_attr(not(feature = "std"), no_std, no_main)]
 
+pub use bounded_collections::{BoundedBTreeMap, BoundedBTreeSet, BoundedVec, ConstU32};
+//use scale::{Decode, Encode, MaxEncodedLen};
+
 pub mod storage_keys;
+
+// /// Some way of identifying an account on the chain.
+// #[derive(Encode, Decode, Debug, MaxEncodedLen)]
+// pub struct AccountId([u8; 32]);
+// Id used for identifying non-fungible collections.
+pub type CollectionId = u32;
+// Id used for identifying non-fungible items.
+pub type ItemId = u32;
+/// The maximum length of an attribute key.
+pub type KeyLimit = ConstU32<64>;
+/// The maximum approvals an item could have.
+pub type ApprovalsLimit = ConstU32<20>;

pop-api/primitives/src/storage_keys.rs

@@ -1,11 +1,34 @@
+use super::*;
 use scale::{Decode, Encode, MaxEncodedLen};
 
 #[derive(Encode, Decode, Debug, MaxEncodedLen)]
 pub enum RuntimeStateKeys {
+	Nfts(NftsKeys),
 	ParachainSystem(ParachainSystemKeys),
 }
 
 #[derive(Encode, Decode, Debug, MaxEncodedLen)]
 pub enum ParachainSystemKeys {
 	LastRelayChainBlockNumber,
 }
+
+// https://github.com/paritytech/polkadot-sdk/blob/master/substrate/frame/nfts/src/impl_nonfungibles.rs
+#[derive(Encode, Decode, Debug, MaxEncodedLen)]
+pub enum NftsKeys {
+	// Get the details of a collection.
+	Collection(CollectionId),
+	/// Get the owner of the collection, if the collection exists.
+	CollectionOwner(CollectionId),
+	// Get the details of an item.
+	Item(CollectionId, ItemId),
+	/// Get the owner of the item, if the item exists.
+	Owner(CollectionId, ItemId),
+	/// Get the attribute value of `item` of `collection` corresponding to `key`.
+	Attribute(CollectionId, ItemId, BoundedVec<u8, KeyLimit>),
+	// /// Get the custom attribute value of `item` of `collection` corresponding to `key`.
+	// CustomAttribute(AccountId, CollectionId, ItemId, BoundedVec<u8, KeyLimit>),
+	/// Get the system attribute value of `item` of `collection` corresponding to `key`
+	SystemAttribute(CollectionId, Option<ItemId>, BoundedVec<u8, KeyLimit>),
+	/// Get the attribute value of `item` of `collection` corresponding to `key`.
+	CollectionAttribute(CollectionId, BoundedVec<u8, KeyLimit>),
+}

pop-api/src/lib.rs

@@ -6,22 +6,14 @@ pub mod v0;
 use crate::PopApiError::{Balances, Nfts, UnknownStatusCode};
 use ink::{prelude::vec::Vec, ChainExtensionInstance};
 use primitives::storage_keys::*;
-use scale;
 pub use sp_runtime::{BoundedVec, MultiAddress, MultiSignature};
 use v0::RuntimeCall;
-pub use v0::{balances, nfts, state};
+pub use v0::{balances, nfts, relay_chain_block_number, state};
 
-// Id used for identifying non-fungible collections.
-pub type CollectionId = u32;
-
-// Id used for identifying non-fungible items.
-pub type ItemId = u32;
-
-type AccountId = <ink::env::DefaultEnvironment as ink::env::Environment>::AccountId;
-type Balance = <ink::env::DefaultEnvironment as ink::env::Environment>::Balance;
-type BlockNumber = <ink::env::DefaultEnvironment as ink::env::Environment>::BlockNumber;
+type AccountId = <Environment as ink::env::Environment>::AccountId;
+type Balance = <Environment as ink::env::Environment>::Balance;
+type BlockNumber = <Environment as ink::env::Environment>::BlockNumber;
 type StringLimit = u32;
-type KeyLimit = u32;
 type MaxTips = u32;
 
 pub type Result<T> = core::result::Result<T, PopApiError>;

pop-api/src/v0/mod.rs

@@ -1,7 +1,16 @@
+use crate::{
+	primitives::storage_keys::{ParachainSystemKeys, RuntimeStateKeys},
+	BlockNumber, PopApiError,
+};
+
 pub mod balances;
 pub mod nfts;
 pub mod state;
 
+pub fn relay_chain_block_number() -> Result<BlockNumber, PopApiError> {
+	state::read(RuntimeStateKeys::ParachainSystem(ParachainSystemKeys::LastRelayChainBlockNumber))
+}
+
 #[derive(scale::Encode)]
 pub(crate) enum RuntimeCall {
 	#[codec(index = 10)]