From 1cba075938957f4c39fff0c6dcc5920710e02864 Mon Sep 17 00:00:00 2001
From: Bart Van Der Meerssche <bart.vandermeerssche@flukso.net>
Date: Mon, 28 Mar 2011 20:21:38 +0000
Subject: [PATCH] [api] port night rrd updates to webmachine api

---
 server/api/flukso/src/flukso.erl            |  5 +-
 server/api/flukso/src/flukso_sensor_xyz.erl | 51 +++++++++++++++++++--
 2 files changed, 50 insertions(+), 6 deletions(-)

diff --git a/server/api/flukso/src/flukso.erl b/server/api/flukso/src/flukso.erl
index 67cf8da..7862740 100644
--- a/server/api/flukso/src/flukso.erl
+++ b/server/api/flukso/src/flukso.erl
@@ -31,7 +31,10 @@ ensure_started(App) ->
 
 mysql_prepare() ->
     mysql:prepare(permissions, <<"SELECT permissions FROM logger_tokens WHERE meter = ? AND token = ?">>),
-    mysql:prepare(device_key, <<"SELECT sha FROM (logger_devices ld INNER JOIN logger_meters lm ON ld.device = lm.device) WHERE lm.meter = ?">>).
+    mysql:prepare(device_key, <<"SELECT sha FROM (logger_devices ld INNER JOIN logger_meters lm ON ld.device = lm.device) WHERE lm.meter = ?">>),
+    mysql:prepare(sensor_props, <<"SELECT uid, device, night FROM logger_meters WHERE meter = ?">>),
+    mysql:prepare(sensor_update, <<"UPDATE logger_meters SET access = ?, night = ?, value = ? WHERE meter = ?">>),
+    mysql:prepare(timezone, <<"SELECT timezone FROM users WHERE uid = ?">>).
 
 %% @spec start_link() -> {ok,Pid::pid()}
 %% @doc Starts the app for inclusion in a supervisor tree
diff --git a/server/api/flukso/src/flukso_sensor_xyz.erl b/server/api/flukso/src/flukso_sensor_xyz.erl
index 776aa65..47044e2 100644
--- a/server/api/flukso/src/flukso_sensor_xyz.erl
+++ b/server/api/flukso/src/flukso_sensor_xyz.erl
@@ -115,8 +115,8 @@ content_types_provided(ReqData, State) ->
 
 to_json(ReqData, #state{rrdSensor = RrdSensor, rrdStart = RrdStart, rrdEnd = RrdEnd, rrdResolution = RrdResolution, rrdFactor = RrdFactor, jsonpCallback = JsonpCallback} = State) -> 
     case wrq:get_qs_value("interval", ReqData) of
-        "night"   -> Path = NIGHT_PATH;
-        _Interval -> Path = BASE_PATH
+        "night"   -> Path = ?NIGHT_PATH;
+        _Interval -> Path = ?BASE_PATH
     end,
 
 %% debugging: io:format("~s~n", [erlrrd:c([[Path, [RrdSensor|".rrd"]], "AVERAGE", ["-s ", RrdStart], ["-e ", RrdEnd], ["-r ", RrdResolution]])]),
@@ -143,13 +143,54 @@ process_post(ReqData, #state{rrdSensor = RrdSensor} = State) ->
     {struct, JsonData} = mochijson2:decode(wrq:req_body(ReqData)),
     Measurements = proplists:get_value(<<"measurements">>, JsonData),
     RrdData = [[integer_to_list(Time), ":", integer_to_list(Counter), " "] || [Time, Counter] <- Measurements],
+    [LastTimestamp, LastValue] = lists:last(Measurements),
+
+    {data, Result} = mysql:execute(pool, sensor_props, [RrdSensor]),
+    [[Uid, _Device, Midnight]] = mysql:get_result_rows(Result),
 
 %debugging: io:format("~s~n", [[Path, [RrdSensor|".rrd"], " ", RrdData]]),
     
-    case erlrrd:update([BASE_PATH, [RrdSensor|".rrd"], " ", RrdData]) of
-        {ok, _RrdResponse} -> RrdResponse = "ok";
-        {error, RrdResponse} -> true
+    case erlrrd:update([?BASE_PATH, [RrdSensor|".rrd"], " ", RrdData]) of
+        {ok, _RrdResponse} ->
+            RrdResponse = "ok",
+            NewMidnight = update_night(RrdSensor, Uid, Midnight, LastTimestamp),
+            mysql:execute(pool, sensor_update, [unix_time(), NewMidnight, LastValue, RrdSensor]);
+
+        {error, RrdResponse} ->
+            true
     end,
 
     JsonResponse = mochijson2:encode({struct, [{<<"response">>, list_to_binary(RrdResponse)}]}),
     {true , wrq:set_resp_body(JsonResponse, ReqData), State}.
+
+update_night(RrdSensor, Uid, Midnight, LastTimestamp) when LastTimestamp > Midnight + 6 * ?HOUR ->
+    LastMidnight = calculate_midnight(unix_time(), Uid),
+
+    case erlrrd:fetch(erlrrd:c([[?BASE_PATH, [RrdSensor|".rrd"]], "AVERAGE", ["-s ", integer_to_list(LastMidnight + 2 * ?HOUR)], ["-e ", integer_to_list(LastMidnight + 5 * ?HOUR)], ["-r ", integer_to_list(?QUARTER)]])) of
+        {ok, Response} ->
+            Filtered = [re:split(X, "[:][ ]", [{return,list}]) || [X] <- Response, string:str(X, ":") == 11],
+            Datapoints = [list_to_float(Y) || [_X, Y] <- Filtered, string:len(Y) /= 3],
+            NightAverage = lists:foldl(fun(X, Sum) -> X / 12 + Sum end, 0, Datapoints),
+
+%debugging: io:format("~s~n", [[?NIGHT_PATH, [RrdSensor|".rrd"], " ", integer_to_list(LastMidnight + 5 * ?HOUR), ":", float_to_list(NightAverage)]]),
+
+            erlrrd:update([?NIGHT_PATH, [RrdSensor|".rrd"], " ", integer_to_list(LastMidnight + 5 * ?HOUR), ":", float_to_list(NightAverage)]);
+        {error, _Reason} ->
+            true
+    end,
+
+    LastMidnight + ?DAY;
+update_night(_RrdSensor, _Uid, Midnight, _LastTimestamp) ->
+    Midnight.
+
+calculate_midnight(Timestamp, Uid) ->
+    {data, Result} = mysql:execute(pool, timezone, [Uid]),
+    [[TimezoneChar8]] = mysql:get_result_rows(Result),
+    Timezone = list_to_integer(binary_to_list(TimezoneChar8)),
+
+    closest_midnight(trunc(Timestamp/?DAY + 1) * ?DAY - Timezone, Timestamp).
+
+closest_midnight(ProposedMidnight, Timestamp) when ProposedMidnight > Timestamp ->
+    closest_midnight(ProposedMidnight - ?DAY, Timestamp);
+closest_midnight(ProposedMidnight, _Timestamp) ->
+    ProposedMidnight.