From d23eec1081fe2a1092df99db0611a39cd38242b0 Mon Sep 17 00:00:00 2001
From: Ryan Casey <ryepdx@gmail.com>
Date: Fri, 21 Aug 2015 09:49:18 -0700
Subject: [PATCH] Change mining script to mine periodically and use filters
 instead of polling.

---
 js/mine.js | 123 ++++++++++++++++++++++++++++++++++++++++++-----------
 1 file changed, 99 insertions(+), 24 deletions(-)

diff --git a/js/mine.js b/js/mine.js
index c03fe5ec..27f3460d 100644
--- a/js/mine.js
+++ b/js/mine.js
@@ -1,16 +1,49 @@
-var miner_var;
+// Adapted from Iuri Matias' Embark framework
+// https://github.com/iurimatias/embark-framework
+// Modified by ryepdx to mine at regular intervals.
+(function() {
+  var main = function () {
+    /* TODO: Find a way to load mining config from YML.
+     
+    if (!loadScript("config.js")) {
+      console.log("== config.js not found");
+    }
 
-if (admin.miner === undefined) {
-  miner_var = miner;
-}
-else {
-  miner_var = admin.miner;
-}
+    if (typeof(config) === "undefined") {
+      config = {};
+      console.log("== config is undefined, proceeding with defaults");
+    }
 
-miner_var.setEtherbase(web3.eth.accounts[0]);
+    In the meantime, just set an empty config object.
+    */
+    config = {}
+
+    defaults = {
+      interval_ms: 15000,
+      mine_pending_txns: true,
+      mine_periodically: true,
+      mine_normally: false,
+      threads: 1
+    }
+
+    for (key in defaults) {
+      if (config[key] === undefined) {
+        config[key] = defaults[key];
+      }
+    }
+
+    var miner_obj = (admin.miner === undefined) ? miner : admin.miner;
+
+    if (config.mine_normally) {
+        miner_obj.start(config.threads);
+        return;
+    }
+    miner_obj.stop();
+
+    if (config.mine_periodically) start_periodic_mining(config, miner_obj);
+    if (config.mine_pending_txns) start_transaction_mining(config, miner_obj);
+  };
 
-setInterval(function() {
-  var minimalAmount = (web3.eth.getBalance(web3.eth.coinbase) >= 15000000000000000000);
   var pendingTransactions = function() {
     if (web3.eth.pendingTransactions === undefined || web3.eth.pendingTransactions === null) {
       return txpool.status.pending || txpool.status.queued;
@@ -21,19 +54,61 @@ setInterval(function() {
     else {
       return web3.eth.pendingTransactions.length > 0 || web3.eth.getBlock('pending').transactions.length > 0;
     }
-  }
+  };
 
-  if(!web3.eth.mining && (!minimalAmount || pendingTransactions())) {
-    if (!minimalAmount) { console.log("=== minimal ether amount not reached yet") }
-    if (pendingTransactions()) { console.log("=== there are pending transactions") }
-    console.log("=== start mining");
-    miner_var.start();
-  }
-  else if (web3.eth.mining && minimalAmount && !pendingTransactions()) {
-    if (minimalAmount) { console.log("=== minimal ether amount reached") }
-    if (!pendingTransactions()) { console.log("=== no pending transactions") }
-    console.log("=== stop mining");
-    miner_var.stop();
-  }
-}, 1000)
+  var start_periodic_mining = function (config, miner_obj) {
+    var last_mined_ms = Date.now();
+    var timeout_set = false;
+
+    miner_obj.start(config.threads);
+    web3.eth.filter("latest").watch(function () {
+      if ((config.mine_pending_txns && pendingTransactions()) || timeout_set) {
+        return;
+      }
+
+      timeout_set = true;
+
+      var now = Date.now();
+      var ms_since_block = now - last_mined_ms;
+      last_mined_ms = now;
+
+      var next_block_in_ms;
+
+      if (ms_since_block > config.interval_ms) {
+        next_block_in_ms = 0;
+      } else {
+        next_block_in_ms = (config.interval_ms - ms_since_block);
+      }
+
+      miner_obj.stop();
+      console.log("== Looking for next block in " + next_block_in_ms + "ms");
+
+      setTimeout(function () {
+        console.log("== Looking for next block");
+        timeout_set = false;
+        miner_obj.start(config.threads);
+      }, next_block_in_ms);
+    });
+  };
+
+  var start_transaction_mining = function (config, miner_obj) {
+    web3.eth.filter("pending").watch(function () {
+      if (miner_obj.hashrate > 0) return;
+
+      console.log("== Pending transactions! Looking for next block...");
+      miner_obj.start(config.threads);
+    });
+    
+    if (config.mine_periodically) return;
+
+    web3.eth.filter("latest").watch(function () {
+      if (!pendingTransactions()) {
+        console.log("== No transactions left. Stopping miner...");
+        miner_obj.stop();
+      }
+    });
+  };
+
+  main();
+})();