From ba1195a6dbb6bb9a23c9377913e488522a7208a2 Mon Sep 17 00:00:00 2001
From: Benjamin DENEUX <b.deneux@okp4.com>
Date: Tue, 21 Feb 2023 15:02:50 +0100
Subject: [PATCH] feat(logic): bech32_address/3 predicate conversion in one way

---
 x/logic/interpreter/registry.go |  1 +
 x/logic/predicate/address.go    | 27 +++++++++++++++++++++++++++
 2 files changed, 28 insertions(+)
 create mode 100644 x/logic/predicate/address.go

diff --git a/x/logic/interpreter/registry.go b/x/logic/interpreter/registry.go
index 6dfefb64..c820bce5 100644
--- a/x/logic/interpreter/registry.go
+++ b/x/logic/interpreter/registry.go
@@ -117,6 +117,7 @@ var Registry = map[string]RegistryEntry{
 	"did_components/2":          {predicate.DIDComponents, 1},
 	"sha_hash/2":                {predicate.SHAHash, 1},
 	"hex_bytes/2":               {predicate.HexBytes, 1},
+	"bech32_address/3":          {predicate.Bech32Address, 1},
 }
 
 // RegistryNames is the list of the predicate names in the Registry.
diff --git a/x/logic/predicate/address.go b/x/logic/predicate/address.go
new file mode 100644
index 00000000..e0dc837f
--- /dev/null
+++ b/x/logic/predicate/address.go
@@ -0,0 +1,27 @@
+package predicate
+
+import (
+	"context"
+	"fmt"
+
+	bech322 "github.com/cosmos/cosmos-sdk/types/bech32"
+	"github.com/ichiban/prolog/engine"
+	"github.com/okp4/okp4d/x/logic/util"
+)
+
+func Bech32Address(vm *engine.VM, hrp, address, bech32 engine.Term, cont engine.Cont, env *engine.Env) *engine.Promise {
+	return engine.Delay(func(ctx context.Context) *engine.Promise {
+		switch b := env.Resolve(bech32).(type) {
+		case engine.Variable:
+			return nil
+		case engine.Atom:
+			h, a, err := bech322.DecodeAndConvert(b.String())
+			if err != nil {
+				return engine.Error(fmt.Errorf("bech32_address/3: failed convert bech32 encoded string to base64: %w", err))
+			}
+			return engine.Unify(vm, Tuple(hrp, address), Tuple(util.StringToTerm(h), BytesToList(a)), cont, env)
+		default:
+			return engine.Error(fmt.Errorf("bech32_address/3: invalid data type: %T, should be Atom or Variable", b))
+		}
+	})
+}