feat: modified bitcoin_transaction_script to infer flags (#278)

<!-- enter the gh issue after hash -->

- [ ] resolves
#277
- [ ] follows contribution
[guide](https://github.com/keep-starknet-strange/shinigami/blob/main/CONTRIBUTING.md)
- [ ] code change includes tests

<!-- PR description below -->

packages/cmds/src/main.cairo

@@ -203,14 +203,27 @@ fn backend_debug(input: InputData) -> u8 {
 #[derive(Drop)]
 struct ValidateRawInput {
     raw_transaction: ByteArray,
-    utxo_hints: Array<UTXO>
+    utxo_hints: Array<UTXO>,
+    flags: ByteArray,
 }
 
 fn run_raw_transaction(mut input: ValidateRawInput) -> u8 {
     println!("Running Bitcoin Script with raw transaction: '{}'", input.raw_transaction);
     let raw_transaction = hex_to_bytecode(@input.raw_transaction);
     let transaction = EngineInternalTransactionTrait::deserialize(raw_transaction);
+
+    // Parse the flags
+    let script_flags = flags::parse_flags(input.flags);
+    println!("Script flags: {}", script_flags);
+
+    // For coinbase transactions, we expect no UTXO hints since it creates new coins
+    if input.utxo_hints.is_empty() {
+        println!("Potential coinbase transaction detected - skipping validation");
+        return 1;
+    }
+
     let mut utxo_hints = array![];
+
     for hint in input
         .utxo_hints
         .span() {
@@ -225,7 +238,8 @@ fn run_raw_transaction(mut input: ValidateRawInput) -> u8 {
                     }
                 );
         };
-    let res = validate::validate_transaction(@transaction, 0, utxo_hints);
+
+    let res = validate::validate_transaction(@transaction, script_flags, utxo_hints);
     match res {
         Result::Ok(_) => {
             println!("Execution successful");

scripts/get_tx_from_block.sh

@@ -0,0 +1,42 @@
+#!/bin/bash
+#
+# This script fetches a transaction hash using block height and transaction index
+# Usage: ./get_tx_from_block.sh <block_height> <tx_index>
+
+if [ "$#" -ne 2 ]; then
+    echo "Usage: $0 <block_height> <tx_index>"
+    echo "Example: $0 869322 1"
+    exit 1
+fi
+
+BLOCK_HEIGHT=$1
+TX_INDEX=$2
+
+RPC_API="https://bitcoin-mainnet.public.blastapi.io"
+
+# First, get the block hash for the given height
+BLOCK_HASH_RES=$(curl -s -X POST -H "Content-Type: application/json" \
+    -d "{\"jsonrpc\":\"1.0\",\"id\":0,\"method\":\"getblockhash\",\"params\":[$BLOCK_HEIGHT]}" \
+    $RPC_API)
+
+BLOCK_HASH=$(echo $BLOCK_HASH_RES | jq -r '.result')
+
+if [ -z "$BLOCK_HASH" ] || [ "$BLOCK_HASH" = "null" ]; then
+    echo "Error: Could not fetch block hash for height $BLOCK_HEIGHT"
+    exit 1
+fi
+
+# Then, get the block data which includes all transaction hashes
+BLOCK_DATA_RES=$(curl -s -X POST -H "Content-Type: application/json" \
+    -d "{\"jsonrpc\":\"1.0\",\"id\":0,\"method\":\"getblock\",\"params\":[\"$BLOCK_HASH\"]}" \
+    $RPC_API)
+
+# Extract the transaction hash at the specified index
+TX_HASH=$(echo $BLOCK_DATA_RES | jq -r ".result.tx[$TX_INDEX]")
+
+if [ -z "$TX_HASH" ] || [ "$TX_HASH" = "null" ]; then
+    echo "Error: Could not find transaction at index $TX_INDEX in block $BLOCK_HEIGHT"
+    exit 1
+fi
+
+echo $TX_HASH

scripts/run_bitcoin_transaction.sh

@@ -5,6 +5,14 @@
 SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 BASE_DIR=$SCRIPT_DIR/..
 
+# BIP activation heights (mainnet)
+BIP_16_BLOCK_HEIGHT=173805  # P2SH
+BIP_66_BLOCK_HEIGHT=363725  # Strict DER signatures
+BIP_65_BLOCK_HEIGHT=388381  # CHECKLOCKTIMEVERIFY
+BIP_112_BLOCK_HEIGHT=419328 # CHECKSEQUENCEVERIFY
+BIP_141_BLOCK_HEIGHT=481824 # SegWit
+BIP_341_BLOCK_HEIGHT=709632 # Taproot
+
 TXID=$1
 
 RPC_API="https://bitcoin-mainnet.public.blastapi.io"
@@ -16,8 +24,8 @@ RPC_API="https://bitcoin-mainnet.public.blastapi.io"
 #    pub amount: i64,
 #    pub pubkey_script: ByteArray,
 #    pub block_height: i32,
-#    // TODO: flags?
-#} 
+#    pub flags: ByteArray,
+#}
 
 # Fetch the transaction
 RES=$(curl -s -X POST -H "Content-Type: application/json" -d "{\"jsonrpc\":\"1.0\",\"id\":0,\"method\":\"getrawtransaction\",\"params\":[\"$TXID\", true]}" $RPC_API)
@@ -34,40 +42,101 @@ RAW_TX_INPUT=$(sed 's/^\[\(.*\)\]$/\1/' <<< $RAW_TX_TEXT)
 VINS=$(echo $RES | jq '.result.vin')
 # echo "VINS: $VINS"
 
-BLOCK_HEIGHT=0 # TODO?
-AMOUNT=0 # TODO?
-UTXOS=""
-for vin in $(echo $VINS | jq -r '.[] | @base64'); do
-    _jq() {
-     echo ${vin} | base64 --decode | jq -r ${1}
-    }
-
-    TXID=$(echo $(_jq '.txid'))
-    VOUT=$(echo $(_jq '.vout'))
-
-    # Fetch the transaction
-    RES=$(curl -s -X POST -H "Content-Type: application/json" -d "{\"jsonrpc\":\"1.0\",\"id\":0,\"method\":\"getrawtransaction\",\"params\":[\"$TXID\", true]}" $RPC_API)
-
-    # AMOUNT=$(echo $RES | jq ".result.vout[$VOUT].value")
-    # echo "AMOUNT: $AMOUNT"
+# Get block hash from transaction
+BLOCK_HASH=$(echo $RES | jq -r '.result.blockhash')
+# Fetch block info to get height
+BLOCK_INFO=$(curl -s -X POST -H "Content-Type: application/json" -d "{\"jsonrpc\":\"1.0\",\"id\":0,\"method\":\"getblock\",\"params\":[\"$BLOCK_HASH\"]}" $RPC_API)
+BLOCK_HEIGHT=$(echo $BLOCK_INFO | jq -r '.result.height')
+echo "BLOCK_HEIGHT: $BLOCK_HEIGHT"
+BLOCK_VERSION=$(echo $BLOCK_INFO | jq -r '.result.version')
+
+# Check if this is a coinbase transaction
+IS_COINBASE=false
+VIN_TXID=$(echo $RES | jq -r '.result.vin[0].txid')
+if [ "$VIN_TXID" = "null" ] || [ "$VIN_TXID" = "0000000000000000000000000000000000000000000000000000000000000000" ]; then
+    IS_COINBASE=true
+    echo "Detected coinbase transaction"
+    FLAGS=""  # Empty flags for coinbase
+else
+    # Initialize empty flags string
+    FLAGS=""
+
+    # BIP16 (P2SH)
+    if [ $BLOCK_HEIGHT -ge $BIP_16_BLOCK_HEIGHT ]; then
+        FLAGS="P2SH"
+    fi
+
+    # BIP66 (Strict DER signatures)
+    if [ $BLOCK_VERSION -ge 3 ] && [ $BLOCK_HEIGHT -ge $BIP_66_BLOCK_HEIGHT ]; then
+        [ -n "$FLAGS" ] && FLAGS="$FLAGS,"
+        FLAGS="${FLAGS}DERSIG"
+    fi
+
+    # BIP65 (CHECKLOCKTIMEVERIFY)
+    if [ $BLOCK_VERSION -ge 4 ] && [ $BLOCK_HEIGHT -ge $BIP_65_BLOCK_HEIGHT ]; then
+        [ -n "$FLAGS" ] && FLAGS="$FLAGS,"
+        FLAGS="${FLAGS}CHECKLOCKTIMEVERIFY"
+    fi
+
+    # BIP112 (CHECKSEQUENCEVERIFY)
+    if [ $BLOCK_HEIGHT -ge $BIP_112_BLOCK_HEIGHT ]; then
+        [ -n "$FLAGS" ] && FLAGS="$FLAGS,"
+        FLAGS="${FLAGS}CHECKSEQUENCEVERIFY"
+    fi
+
+    # BIP141 (SegWit)
+    if [ $BLOCK_HEIGHT -ge $BIP_141_BLOCK_HEIGHT ]; then
+        [ -n "$FLAGS" ] && FLAGS="$FLAGS,"
+        FLAGS="${FLAGS}WITNESS"
+        FLAGS="${FLAGS},NULLDUMMY"
+    fi
+
+    # BIP341 (Taproot)
+    if [ $BLOCK_HEIGHT -ge $BIP_341_BLOCK_HEIGHT ]; then
+        [ -n "$FLAGS" ] && FLAGS="$FLAGS,"
+        FLAGS="${FLAGS}TAPROOT"
+    fi
+fi
+
+echo "Transaction type: $([ "$IS_COINBASE" = true ] && echo 'Coinbase' || echo 'Regular')"
+echo "Block height: $BLOCK_HEIGHT"
+echo "Script flags: $FLAGS"
+echo "UTXO construction: $UTXOS"
 
-    PUBKEY_SCRIPT=$(echo $RES | jq ".result.vout[$VOUT].scriptPubKey.hex" | tr -d '"')
-    PUBKEY_SCRIPT="0x$PUBKEY_SCRIPT"
-    # echo "PUBKEY_SCRIPT: $PUBKEY_SCRIPT"
-
-    PUBKEY_SCRIPT_TEXT=$($SCRIPT_DIR/text_to_byte_array.sh $PUBKEY_SCRIPT)
-    PUBKEY_SCRIPT_INPUT=$(sed 's/^\[\(.*\)\]$/\1/' <<< $PUBKEY_SCRIPT_TEXT)
-    # echo "PUBKEY_SCRIPT_INPUT: $PUBKEY_SCRIPT_INPUT"
-
-    # Construct UTXO
-    UTXO="{\"amount\":$AMOUNT,\"pubkey_script\":\"$PUBKEY_SCRIPT\",\"block_height\":$BLOCK_HEIGHT}"
-    # echo "UTXO: $UTXO"
-
-    UTXOS="$UTXOS$AMOUNT,$PUBKEY_SCRIPT_INPUT,$BLOCK_HEIGHT,"
-done
-UTXOS=$(sed 's/,$//' <<< $UTXOS)
-
-JOINED_INPUT="[$RAW_TX_INPUT,[$UTXOS]]"
+AMOUNT=0 # TODO?
+if [ "$IS_COINBASE" = true ]; then
+    echo "Setting up empty UTXO list for coinbase transaction"
+    # Leave UTXOS empty for coinbase transactions
+    UTXOS=""
+else
+    UTXOS=""
+    for vin in $(echo $VINS | jq -r '.[] | @base64'); do
+            _jq() {
+                echo ${vin} | base64 --decode | jq -r ${1}
+            }
+
+            TXID=$(echo $(_jq '.txid'))
+            VOUT=$(echo $(_jq '.vout'))
+
+            # Fetch the transaction
+            RES=$(curl -s -X POST -H "Content-Type: application/json" -d "{\"jsonrpc\":\"1.0\",\"id\":0,\"method\":\"getrawtransaction\",\"params\":[\"$TXID\", true]}" $RPC_API)
+
+            AMOUNT=$(echo $RES | jq ".result.vout[$VOUT].value * 100000000 | floor")
+            PUBKEY_SCRIPT=$(echo $RES | jq ".result.vout[$VOUT].scriptPubKey.hex" | tr -d '"')
+            PUBKEY_SCRIPT="0x$PUBKEY_SCRIPT"
+
+            PUBKEY_SCRIPT_TEXT=$($SCRIPT_DIR/text_to_byte_array.sh $PUBKEY_SCRIPT)
+            PUBKEY_SCRIPT_INPUT=$(sed 's/^\[\(.*\)\]$/\1/' <<< $PUBKEY_SCRIPT_TEXT)
+
+            UTXOS="$UTXOS$AMOUNT,$PUBKEY_SCRIPT_INPUT,$BLOCK_HEIGHT"
+        done
+    UTXOS=$(sed 's/,$//' <<< $UTXOS)
+fi
+
+FLAGS_TEXT=$($SCRIPT_DIR/text_to_byte_array.sh "$FLAGS")
+FLAGS_INPUT=$(sed 's/^\[\(.*\)\]$/\1/' <<< $FLAGS_TEXT)
+
+JOINED_INPUT="[$RAW_TX_INPUT,[$UTXOS],$FLAGS_INPUT]"
 # echo "JOINED_INPUT: $JOINED_INPUT"
 
 echo "scarb cairo-run --package shinigami_cmds --function run_raw_transaction \"$JOINED_INPUT\""