From fedbe0d2bc34560b0e18f39aac9dc1fff085004c Mon Sep 17 00:00:00 2001
From: VoR0220 <catalanor0220@gmail.com>
Date: Wed, 6 Jun 2018 14:37:08 -0500
Subject: [PATCH] first attempt at gas estimation using a 3 round fuzzer and
 linking it into the profiler

Signed-off-by: VoR0220 <catalanor0220@gmail.com>
---
 lib/modules/fuzzer/index.js       |  5 +++--
 lib/modules/gasEstimator/index.js | 37 +++++++++++++++++++++++++++++++
 lib/modules/profiler/index.js     |  9 +++++---
 3 files changed, 46 insertions(+), 5 deletions(-)
 create mode 100644 lib/modules/gasEstimator/index.js

diff --git a/lib/modules/fuzzer/index.js b/lib/modules/fuzzer/index.js
index a38dc89ca..1a173fdc1 100644
--- a/lib/modules/fuzzer/index.js
+++ b/lib/modules/fuzzer/index.js
@@ -21,10 +21,11 @@ class ContractFuzzer {
       contract.abiDefinition.filter((x) => x.inputs && x.inputs.length != 0).forEach((abiMethod) => {
         let name = abiMethod.type === "constructor" ? "constructor" : abiMethod.name;
         let inputTypes = abiMethod.inputs.map(input => input.type);
-        fuzzMap[name] = inputTypes.map(input => this.getTypeFuzz(input));
+        fuzzMap[name][i] = inputTypes.map(input => this.getTypeFuzz(input));
       });
+      self.logger.info('\n');
+      for (let key in fuzzMap) self.logger.info(key + ":" + fuzzMap[key][i]);
     }
-    for (let key in fuzzMap) self.logger.info(key + ":" + fuzzMap[key]);
     return fuzzMap;
   }
 
diff --git a/lib/modules/gasEstimator/index.js b/lib/modules/gasEstimator/index.js
new file mode 100644
index 000000000..9095937aa
--- /dev/null
+++ b/lib/modules/gasEstimator/index.js
@@ -0,0 +1,37 @@
+const ContractFuzzer = require('../fuzzer');
+
+class GasEstimator {
+  constructor(embark) {
+    this.embark = embark;
+    this.logger = embark.logger;
+    this.events = embark.events;
+    this.fuzzer = new ContractFuzzer(embark);
+  }
+
+  estimateGas(contractName) {
+    let gasMap = {};
+    this.logger.info("Generating three rounds of fuzz for contract -- ", contractName);
+    let fuzzMap = this.fuzzer.generateFuzz(3, contractName);
+    self.events.request('contracts:contract', contractName, (contract) => {
+      self.logger.info("--  Beginning gastimation for contract -- " + contractName);
+      tempGasMap = {};
+      fuzzMap.forEach((name) => {
+        for (let i in fuzzMap[name]) {
+          tempGasMap[name][i] = contract.methods[name].apply(contract.methods[name], fuzzMap[name][i]).estimateGas();
+        }
+      });
+      tempGasMap.forEach((name) => {
+        if (name === "constructor") {
+          gasMap[name] = contract.gasEstimates.creation.totalCost;
+        } else if (tempGasMap[name][0] !== tempGasMap[name][1] && tempGasMap[name][1] !== tempGasMap[name][2]) {
+          gasMap[name] = 'variable';
+        } else {
+          gasMap[name] = tempGasMap[name][0];
+        }
+      });
+      return gasMap;
+    });
+  }
+}
+
+module.exports = GasEstimator;
diff --git a/lib/modules/profiler/index.js b/lib/modules/profiler/index.js
index f86ad9952..a86f239d2 100644
--- a/lib/modules/profiler/index.js
+++ b/lib/modules/profiler/index.js
@@ -1,10 +1,12 @@
 const asciiTable = require('ascii-table');
+const GasEstimator = require('../gasEstimator');
 
 class Profiler {
   constructor(embark) {
     this.embark = embark;
     this.logger = embark.logger;
     this.events = embark.events;
+    this.gasEstimator = new GasEstimator(embark);
 
     this.registerConsoleCommand();
   }
@@ -12,14 +14,15 @@ class Profiler {
   profile(contractName, contract) {
     const self = this;
     let table = new asciiTable(contractName);
-    table.setHeading('Function', 'Payable', 'Mutability', 'Inputs', 'Outputs');
+    table.setHeading('Function', 'Payable', 'Mutability', 'Inputs', 'Outputs', 'Gas Estimates');
+    let gastimates = self.gasEstimator.estimateGas(contractName);
     contract.abiDefinition.forEach((abiMethod) => {
       switch(abiMethod.type) {
         case "constructor": 
-          table.addRow("constructor", abiMethod.payable, abiMethod.stateMutability, this.formatParams(abiMethod.inputs), this.formatParams(abiMethod.outputs));
+          table.addRow("constructor", abiMethod.payable, abiMethod.stateMutability, this.formatParams(abiMethod.inputs), this.formatParams(abiMethod.outputs), gastimates['constructor']);
           break;
         default:
-          table.addRow(abiMethod.name, abiMethod.payable, abiMethod.stateMutability, this.formatParams(abiMethod.inputs), this.formatParams(abiMethod.outputs));
+          table.addRow(abiMethod.name, abiMethod.payable, abiMethod.stateMutability, this.formatParams(abiMethod.inputs), this.formatParams(abiMethod.outputs), gastimates[abiMethod.name]);
       }
     });
     self.logger.info(table.toString());