authority.ts

import {
    PermissionLevel,
    PermissionLevelType,
    PublicKey,
    PublicKeyType,
    Struct,
    TypeAlias,
    UInt16,
    UInt16Type,
    UInt32,
    UInt32Type,
} from '../'
import {isInstanceOf} from '../utils'

@TypeAlias('weight_type')
export class Weight extends UInt16 {}

@Struct.type('key_weight')
export class KeyWeight extends Struct {
    @Struct.field(PublicKey) key!: PublicKey
    @Struct.field(Weight) weight!: Weight
}

@Struct.type('permission_level_weight')
export class PermissionLevelWeight extends Struct {
    @Struct.field(PermissionLevel) permission!: PermissionLevel
    @Struct.field(Weight) weight!: Weight
}

@Struct.type('wait_weight')
export class WaitWeight extends Struct {
    @Struct.field(UInt32) wait_sec!: UInt32
    @Struct.field(Weight) weight!: Weight
}

export type AuthorityType =
    | Authority
    | {
          threshold: UInt32Type
          keys?: {key: PublicKeyType; weight: UInt16Type}[]
          accounts?: {permission: PermissionLevelType; weight: UInt16Type}[]
          waits?: {wait_sec: UInt32Type; weight: UInt16Type}[]
      }

@Struct.type('authority')
export class Authority extends Struct {
    @Struct.field(UInt32) threshold!: UInt32
    @Struct.field(KeyWeight, {array: true}) keys!: KeyWeight[]
    @Struct.field(PermissionLevelWeight, {array: true}) accounts!: PermissionLevelWeight[]
    @Struct.field(WaitWeight, {array: true}) waits!: WaitWeight[]

    static from(value: AuthorityType): Authority {
        if (isInstanceOf(value, Authority)) {
            return value
        }
        const rv = super.from({
            keys: [],
            accounts: [],
            waits: [],
            ...value,
        }) as Authority
        rv.sort()
        return rv
    }

    /** Total weight of all waits. */
    get waitThreshold(): number {
        return this.waits.reduce((val, wait) => val + wait.weight.toNumber(), 0)
    }

    /** Weight a key needs to sign for this authority. */
    get keyThreshold(): number {
        return this.threshold.toNumber() - this.waitThreshold
    }

    /** Return the weight for given public key, or zero if it is not included in this authority. */
    keyWeight(publicKey: PublicKeyType): number {
        const weight = this.keys.find(({key}) => key.equals(publicKey))
        return weight ? weight.weight.toNumber() : 0
    }

    /**
     * Check if given public key has permission in this authority,
     * @attention Does not take indirect permissions for the key via account weights into account.
     * @param publicKey The key to check.
     * @param includePartial Whether to consider auths where the key is included but can't be reached alone (e.g. multisig).
     */
    hasPermission(publicKey: PublicKeyType, includePartial = false): boolean {
        const threshold = includePartial ? 1 : this.keyThreshold
        const weight = this.keyWeight(publicKey)
        return weight >= threshold
    }

    /**
     * Sorts the authority weights in place, should be called before including the authority in a `updateauth` action or it might be rejected.
     */
    sort() {
        // This hack satisfies the constraints that authority weights, see: https://github.com/wharfkit/antelope/issues/8
        this.keys.sort((a, b) => String(a.key).localeCompare(String(b.key)))
        this.accounts.sort((a, b) => String(a.permission).localeCompare(String(b.permission)))
        this.waits.sort((a, b) => String(a.wait_sec).localeCompare(String(b.wait_sec)))
    }
}