geohashd.nt

geohashd.nt.d

module geohashd;

import std.smtp, std.process, std.string, std.getopt, std.file, std.hash.md5;
import c.time;

string dateformat(int i) {
  if (i < 10) return "0$i";
  else return "$i";
}

string htmlEscape(string s) {
  return s.replace(" ", "%20").replace("\"", "%22").replace(",", "%2C");
}

void main(string[] args) {
  set-handler(UnrecoverableError uerr) {
    writeln "$uerr".replace(":", "\n");
    invoke-exit "ret";
  }
  define-exit "ret" return;
  string home, area, email, smtpdata;
  float maxdist;
  bool walk;
  void printHelpData() {
    writeln "Usage: geohashd [--home, -h] [--maxdist, -d]";
    writeln "                [--area, -a] [--email, -m] [--walk, -w]";
    writeln "                [--smtpdata, -s] [--help, -h]";
    writeln "";
    writeln "Note: geohashd is not authorized to use Google Maps.";
    writeln "It scrapes the webview. As a result, it can suddenly break on updates.";
    writeln "";
    writeln "--home: Home address that you start out at.";
    writeln "--maxdist: maximum distance that you want to drive, in km.";
    writeln "--area: \"latitude,+-longitude\". Target quadrant to search in.";
    writeln "--email: Address to mail when a location is found.";
    writeln "--walk: Whether to use Google Maps in walking mode. For people without cars.";
    writeln "--smtpdata: username:password@smtpserver . SMTP server that's used to send email";
    writeln "--help: this page";
    writeln "";
  }
  bool tHome, tArea, tEmail, tSmtpData, tMaxdist;
  using new Options {
    addLong("home", "h", λ(string s) { home = s; tHome = true; });
    addLong("maxdist", "d", λ(string s) { maxdist = s.atof(); tMaxdist = true; });
    addLong("area", "a", λ(string s) { area = s; tArea = true; });
    addLong("email", "m", λ(string s) { email = s; tEmail = true; });
    addLong("walk", "w", λ{ walk = true; });
    addLong("smtpdata", "s", λ(string s) { smtpdata = s; tSmtpData = true; });
    addLong("help", "h", λ{ printHelpData; });
    args = process args;
  }
  if (!tHome) fail "Please set --home to your home address";
  if (!tArea) fail "Please set --area to your lat/long area (xx, ±yy)";
  if (!tEmail) fail "Please set --email to your email address";
  if (!tSmtpData) fail "Please set --smtpdata to your email info: username:password@host";
  if (!tMaxdist) fail "Please set --maxdist to your maximum interest distance";
  auto currentTime = localtime &auto t1 = time(null);
  auto day = currentTime.tm_mday, month = currentTime.tm_mon + 1, year = currentTime.tm_year + 1900;
  auto correctedTime = currentTime;
  auto lon = area.split(",")[1].atoi();
  if (lon > -30) {
    // this may validly go negative! study man 3 localtime
    correctedTime.tm_mday --; // 30W change
    correctedTime = localtime &auto t2 = mktime correctedTime; // reconstruct
  }
  auto cday = correctedTime.tm_mday, cmonth = correctedTime.tm_mon + 1, cyear = correctedTime.tm_year + 1900;
  // auto url = "http://irc.peeron.com/xkcd/map/data/%Y/%m/%d".insertTimes(cday, cmonth, cyear);
  auto url = "http://geo.crox.net/djia/$cyear/$cmonth/$cday";
  auto opening = readback("wget", ["-q", "-O-", url]).join("");
  auto date = "$(dateformat(year))-$(dateformat(month))-$(dateformat(day))";
  write "Date";
  if (lon > -30) write ", including W30";
  writeln ": $date - $url";
  auto infostring = "$date-$opening";
  MD5Hash hash;
  hash.sum ubyte[]: infostring;
  alias digest = hash.hash;
  double toReal(ubyte[] field) {
    double res = 0;
    double factor = 1;
    for auto value <- field {
      factor /= 0x100;
      res += value * factor;
    }
    return res;
  }
  auto digest1 = toReal(digest[0..8]), digest2 = toReal(digest[8..16]);
  writeln "'$infostring': $digest => $digest1, $digest2";
  
  //                                          remove leading 0
  auto sp = area.split(","), dest = sp[0] ~ "$digest1"[1 .. $] ~ "," ~ sp[1] ~ "$digest2"[1 .. $];
  if (home.length && (home[0] != "\"" || home[$-1] != "\"")) home = "\"$home\"";
  auto groute = "http://maps.google.com/maps?saddr=$home&daddr=$dest&pw=2"~walk?.("&dirflg=w");
  writeln "groute $groute";
  auto grata = readback("wget", ["-q", "-O-", groute]).join(""); // google route data
  auto dist = grata.between("div\\x3e\\x3cb\\x3e", "\\x26").atof();
  writeln "$groute -> $dist km";
  if (dist > maxdist) { writeln "Out of range!"; return; }
  if (dist == 0f) { writeln "Too close. Probably a bug. "; return; }
  writeln "Within range!";
  auto host = smtpdata; string username, pass;
  if (auto at = host.find("@")) {
    username = host[0 .. at];
    host = host[at+1 .. $];
    auto sep = username.find(":");
    if (sep != -1) {
      pass = username[sep+1 .. $];
      username = username[0 .. sep];
    }
  }
  sendmail(=>smtps, email, email,
    "[geohashd] location within range: $(dist)km for $date",
    host => host, logindata => "$username:$pass", =>dbg,
    "A geohashing location has been discovered in your area that is close enough to reach: $dist km!
The link to the Google Maps data is $(groute.htmlEscape()) . Have fun!"
  );
}