[Polkadot] Add delegations query (#435)

* first step, simplified query is working

* lint

* Get validator info from val dictionary

* cleanup, fix comission

* fix

* faster solution

* remove types we dont need in store

* @ALEKSEI suggestions

* fix

* fix

* simplify as @imbeone suggested

* simplify, thanks @Bitcoinera!

* re adding array check

* delegationReducer

* fix

lib/reducers/polkadotV0-reducers.js

@@ -44,7 +44,7 @@ function validatorReducer(network, validator) {
     uptimePercentage: undefined,
     tokens: validator.tokens,
     commissionUpdateTime: undefined,
-    commission: validator.validatorPrefs.commission / 100000000,
+    commission: validator.validatorPrefs.commission / 10000000,
     maxCommission: undefined,
     maxChangeCommission: undefined,
     status: `ACTIVE`, // We are fetching current session active validators only (not intentions)
@@ -53,7 +53,8 @@ function validatorReducer(network, validator) {
     selfStake:
       (
         BigNumber(validator.exposure.own).toNumber() / POLKADOT_CONVERSION
-      ).toFixed(9) || 0
+      ).toFixed(9) || 0,
+    nominations: validator.nominations
   }
 }
 
@@ -69,8 +70,20 @@ function balanceReducer(balance) {
   ]
 }
 
+function delegationReducer(delegation, validator) {
+  return {
+    validatorAddress: validator.operatorAddress,
+    delegatorAddress: delegation.who,
+    validator,
+    amount: BigNumber(delegation.value)
+      .dividedBy(10 ** 12) // FIXME: Replace by constant
+      .toFixed(9)
+  }
+}
+
 module.exports = {
   blockReducer,
   validatorReducer,
-  balanceReducer
+  balanceReducer,
+  delegationReducer
 }

lib/source/polkadotV0-source.js

@@ -149,6 +149,9 @@ class polkadotAPI {
         const validatorStake = new BigNumber(validator.exposure.total)
         validator.votingPower = validatorStake.div(networkTotalStake).toNumber()
         validator.tokens = validatorStake / 1e12 // IMPROVE IT! Add denom decimal places to network.js
+        validator.nominations = JSON.parse(
+          JSON.stringify(validator.exposure.others)
+        ) // Added for faster delegations search
       } else {
         validator.votingPower = 0
       }
@@ -188,6 +191,24 @@ class polkadotAPI {
     const accountBalances = await api.query.staking.bonded(delegatorAddress) // or stashId?
     console.log('ACCOUNT', JSON.stringify(accountBalances))
   }
+
+  async getDelegationsForDelegatorAddress(
+    delegatorAddress,
+    validatorsDictionary
+  ) {
+    if (!Array.isArray(validatorsDictionary)) return []
+    let delegations = []
+    validatorsDictionary.forEach(validator => {
+      validator.nominations.forEach(nomination => {
+        if (delegatorAddress === nomination.who) {
+          delegations.push(
+            this.reducers.delegationReducer(nomination, validator)
+          )
+        }
+      })
+    })
+    return delegations
+  }
 }
 
 module.exports = polkadotAPI