From 983da3c24f7f932a7006950c51adef2e7dacf42b Mon Sep 17 00:00:00 2001
From: benbierens <thatbenbierens@gmail.com>
Date: Mon, 4 Mar 2024 09:43:35 +0100
Subject: [PATCH] functional implementation

---
 codex/slots/proofs/backendfactory.nim | 52 +++++++++++++++++++--------
 1 file changed, 37 insertions(+), 15 deletions(-)

diff --git a/codex/slots/proofs/backendfactory.nim b/codex/slots/proofs/backendfactory.nim
index e9f55093..8c02f781 100644
--- a/codex/slots/proofs/backendfactory.nim
+++ b/codex/slots/proofs/backendfactory.nim
@@ -2,6 +2,7 @@ import os
 import httpclient
 import zip/zipfiles
 import pkg/chronos
+import pkg/chronicles
 import pkg/questionable
 import pkg/confutils/defs
 import pkg/stew/io2
@@ -30,19 +31,20 @@ proc initializeFromConfig(
     endsWith($config.circomZkey, ".zkey"):
     return failure("Circom zkey file not accessible")
 
+  trace "Initialized prover backend from cli config"
   success(initializeCircomBackend(
     $config.circomR1cs,
     $config.circomWasm,
     $config.circomZkey))
 
 proc r1csFilePath(config: CodexConf): string =
-  config.dataDir / "circuit.r1cs"
+  config.dataDir / "proof_main.r1cs"
 
 proc wasmFilePath(config: CodexConf): string =
-  config.dataDir / "circuit.wasm"
+  config.dataDir / "proof_main.wasm"
 
 proc zkeyFilePath(config: CodexConf): string =
-  config.dataDir / "circuit.zkey"
+  config.dataDir / "proof_main.zkey"
 
 proc zipFilePath(config: CodexConf): string =
   config.dataDir / "circuit.zip"
@@ -51,6 +53,7 @@ proc initializeFromCeremonyFiles(config: CodexConf): ?!AnyBackend =
   if fileExists(config.r1csFilePath) and
     fileExists(config.wasmFilePath) and
     fileExists(config.zkeyFilePath):
+    trace "Initialized prover backend from local files"
     return success(initializeCircomBackend(
       config.r1csFilePath,
       config.wasmFilePath,
@@ -58,28 +61,47 @@ proc initializeFromCeremonyFiles(config: CodexConf): ?!AnyBackend =
 
   failure("Ceremony files not found")
 
-proc downloadCeremonyUrl(
+proc downloadCeremony(
   config: CodexConf,
-  proofCeremonyUrl: string
-) =
-  var client = newHttpClient()
-  client.downloadFile(
-    "https://circuit.codex.storage/proving-key/" & proofCeremonyUrl, config.zipFilePath)
+  ceremonyHash: string
+): ?!void =
+  # TODO:
+  # In the future, the zip file will be stored in the Codex network
+  # instead of a url + ceremonyHash, we'll get a CID from the marketplace contract.
+
+  echo "OVERRIDE!"
+  let hash = "1f512a1c6a089eff7eb22b810438c34fc59d4b0e7935dbc77ec77255d39ec094"
+
+  let url = "https://circuit.codex.storage/proving-key/" & hash # was ceremonyHash
+  trace "Downloading ceremony file", url, filepath = config.zipFilePath
+  try:
+    # Nim's default webclient does not support SSL on all platforms.
+    # Not without shipping additional binaries and cert-files... :(
+    # So we're using curl for now.
+    var rc = execShellCmd("curl -o " & config.zipFilePath & " " & url)
+    if not rc == 0:
+      return failure("Download failed with return code: " & $rc)
+  except Exception as exc:
+    return failure(exc.msg)
+  trace "Download completed."
+  success()
 
 proc unzipCeremonyFile(
   config: CodexConf): ?!void =
+  trace "Unzipping..."
   var z: ZipArchive
   if not z.open(config.zipFilePath):
     return failure("Unable to open zip file: " & config.zipFilePath)
   z.extractAll($config.dataDir)
   success()
 
-proc initializeFromCeremonyUrl(
+proc initializeFromCeremonyHash(
   config: CodexConf,
-  proofCeremonyUrl: ?string): Future[?!AnyBackend] {.async.} =
+  ceremonyHash: ?string): Future[?!AnyBackend] {.async.} =
 
-  if url =? proofCeremonyUrl:
-    downloadCeremonyUrl(config, url)
+  if hash =? ceremonyHash:
+    if dlErr =? downloadCeremony(config, hash).errorOption:
+      return failure(dlErr)
     if err =? unzipCeremonyFile(config).errorOption:
       return failure(err)
     without backend =? initializeFromCeremonyFiles(config), err:
@@ -90,13 +112,13 @@ proc initializeFromCeremonyUrl(
 
 proc initializeBackend*(
   config: CodexConf,
-  proofCeremonyUrl: ?string): Future[?!AnyBackend] {.async.} =
+  ceremonyHash: ?string): Future[?!AnyBackend] {.async.} =
 
   without backend =? initializeFromConfig(config), cliErr:
     info "Could not initialize prover backend from CLI options...", msg = cliErr.msg
     without backend =? initializeFromCeremonyFiles(config), localErr:
       info "Could not initialize prover backend from local files...", msg = localErr.msg
-      without backend =? (await initializeFromCeremonyUrl(config, proofCeremonyUrl)), urlErr:
+      without backend =? (await initializeFromCeremonyHash(config, ceremonyHash)), urlErr:
         warn "Could not initialize prover backend from ceremony url...", msg = urlErr.msg
         return failure(urlErr)
   return success(backend)