using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using System.Net;
using System.Text.RegularExpressions;
using ICSharpCode.SharpZipLib.Zip;
using System.Threading;
using System.Collections;
namespace ArdupilotMega
{
class srtm
{
public static string datadirectory = "./srtm/";
static List<string> allhgts = new List<string>();
static object objlock = new object();
static Thread requestThread;
static List<string> queue = new List<string>();
static Hashtable fnamecache = new Hashtable();
static Hashtable filecache = new Hashtable();
static Dictionary<string, short[,]> cache = new Dictionary<string, short[,]>();
public static int getAltitude(double lat, double lng, double zoom)
{
short alt = 0;
//lat += 1 / 1199.0;
//lng -= 1 / 1201f;
// lat -35.115676879882812 double
// lng 117.94178754638671 double
// alt 70 short
int x = (lng < 0) ? (int)(lng-1) : (int)lng;//(int)Math.Floor(lng);
int y = (lat < 0) ? (int)(lat - 1) : (int)lat; ;//(int)Math.Floor(lat);
string ns;
if (y > 0)
ns = "N";
else
ns = "S";
string ew;
if (x > 0)
ew = "E";
else
ew = "W";
if (fnamecache[y] == null)
fnamecache[y] = Math.Abs(y).ToString("00");
if (fnamecache[1000 + x] == null)
fnamecache[1000 + x] = Math.Abs(x).ToString("000");
string filename = ns + fnamecache[y] + ew + fnamecache[1000 + x] + ".hgt";
try
{
if (cache.ContainsKey(filename) || File.Exists(datadirectory + Path.DirectorySeparatorChar + filename))
{ // srtm hgt files
int size = -1;
if (!cache.ContainsKey(filename))
{
FileStream fs = new FileStream(datadirectory + Path.DirectorySeparatorChar + filename, FileMode.Open, FileAccess.Read, FileShare.Read);
if (fs.Length == (1201 * 1201 * 2))
{
size = 1201;
}
else
{
size = 3601;
}
byte[] altbytes = new byte[2];
short[,] altdata = new short[size, size];
int altlat = 0;
int altlng = 0;
while (fs.Read(altbytes, 0, 2) != 0)
{
altdata[altlat, altlng] = (short)((altbytes[0] << 8) + altbytes[1]);
altlat++;
if (altlat >= size)
{
altlng++;
altlat = 0;
}
}
fs.Close();
cache[filename] = altdata;
}
if (cache[filename].Length == (1201 * 1201))
{
size = 1201;
}
else
{
size = 3601;
}
int posx = 0;
int row = 0;
posx = (int)(((float)(lng - x)) * (size * 1));
row = (int)(((float)(lat - y)) * (size * 1));
row = size - row;
return cache[filename][posx, row];
}
string filename2 = "srtm_" + Math.Round((lng + 2.5 + 180) / 5, 0).ToString("00") + "_" + Math.Round((60 - lat + 2.5) / 5, 0).ToString("00") + ".asc";
if (File.Exists(datadirectory + Path.DirectorySeparatorChar + filename2))
{
StreamReader sr = new StreamReader(readFile(datadirectory + Path.DirectorySeparatorChar + filename2));
int nox = 0;
int noy = 0;
float left = 0;
float top = 0;
int nodata = -9999;
float cellsize = 0;
int rowcounter = 0;
float wantrow = 0;
float wantcol = 0;
while (!sr.EndOfStream)
{
string line = sr.ReadLine();
if (line.StartsWith("ncols"))
{
nox = int.Parse(line.Substring(line.IndexOf(' ')));
//hgtdata = new int[nox * noy];
}
else if (line.StartsWith("nrows"))
{
noy = int.Parse(line.Substring(line.IndexOf(' ')));
//hgtdata = new int[nox * noy];
}
else if (line.StartsWith("xllcorner"))
{
left = float.Parse(line.Substring(line.IndexOf(' ')));
}
else if (line.StartsWith("yllcorner"))
{
top = float.Parse(line.Substring(line.IndexOf(' ')));
}
else if (line.StartsWith("cellsize"))
{
cellsize = float.Parse(line.Substring(line.IndexOf(' ')));
}
else if (line.StartsWith("NODATA_value"))
{
nodata = int.Parse(line.Substring(line.IndexOf(' ')));
}
else
{
string[] data = line.Split(new char[] { ' ' });
if (data.Length == (nox + 1))
{
wantcol = (float)((lng - Math.Round(left, 0)));
wantrow = (float)((lat - Math.Round(top, 0)));
wantrow = (int)(wantrow / cellsize);
wantcol = (int)(wantcol / cellsize);
wantrow = noy - wantrow;
if (rowcounter == wantrow)
{
Console.WriteLine("{0} {1} {2} {3} ans {4} x {5}", lng, lat, left, top, data[(int)wantcol], (nox + wantcol * cellsize));
return int.Parse(data[(int)wantcol]);
}
rowcounter++;
}
}
}
//sr.Close();
return alt;
}
else // get something
{
if (zoom >= 15)
{
if (!Directory.Exists(datadirectory))
Directory.CreateDirectory(datadirectory);
if (requestThread == null)
{
Console.WriteLine("Getting " + filename);
queue.Add(filename);
requestThread = new Thread(requestRunner);
requestThread.IsBackground = true;
requestThread.Name = "SRTM request runner";
requestThread.Start();
}
else
{
lock (objlock)
{
if (!queue.Contains(filename))
{
Console.WriteLine("Getting " + filename);
queue.Add(filename);
}
}
}
}
}
}
catch { alt = 0; }
return alt;
}
static MemoryStream readFile(string filename)
{
if (filecache.ContainsKey(filename))
{
return (MemoryStream)filecache[filename];
}
else
{
FileStream fs = new FileStream(filename, FileMode.Open, FileAccess.Read);
byte[] file = new byte[fs.Length];
fs.Read(file, 0, (int)fs.Length);
filecache[filename] = new MemoryStream(file);
fs.Close();
return (MemoryStream)filecache[filename];
}
}
static void requestRunner()
{
while (true)
{
try
{
string item = "";
lock (objlock)
{
if (queue.Count > 0)
{
item = queue[0];
}
}
if (item != "")
{
get3secfile(item);
lock (objlock)
{
queue.Remove(item);
}
}
}
catch { }
Thread.Sleep(1000);
}
}
static void get3secfile(object name)
{
string baseurl = "http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/";
// check file doesnt already exist
if (File.Exists(datadirectory + Path.DirectorySeparatorChar + (string)name))
{
FileInfo fi = new FileInfo(datadirectory + Path.DirectorySeparatorChar + (string)name);
if (fi.Length != 0)
return;
}
List<string> list = getListing(baseurl);
foreach (string item in list)
{
List<string> hgtfiles = new List<string>();
hgtfiles = getListing(item);
foreach (string hgt in hgtfiles)
{
if (hgt.Contains((string)name))
{
// get file
gethgt(hgt, (string)name);
return;
}
}
}
}
static void gethgt(string url, string filename)
{
try
{
WebRequest req = HttpWebRequest.Create(url);
WebResponse res = req.GetResponse();
Stream resstream = res.GetResponseStream();
BinaryWriter bw = new BinaryWriter(File.Create(datadirectory + Path.DirectorySeparatorChar + filename + ".zip"));
byte[] buf1 = new byte[1024];
while (resstream.CanRead)
{
int len = resstream.Read(buf1, 0, 1024);
if (len == 0)
break;
bw.Write(buf1, 0, len);
}
bw.Close();
FastZip fzip = new FastZip();
fzip.ExtractZip(datadirectory + Path.DirectorySeparatorChar + filename + ".zip", datadirectory, "");
}
catch { }
}
static List<string> getListing(string url)
{
string name = new Uri(url).AbsolutePath;
name = Path.GetFileName(name.TrimEnd('/'));
List<string> list = new List<string>();
if (File.Exists(datadirectory + Path.DirectorySeparatorChar + name))
{
StreamReader sr = new StreamReader(datadirectory + Path.DirectorySeparatorChar + name);
while (!sr.EndOfStream)
{
list.Add(sr.ReadLine());
}
sr.Close();
return list;
}
try
{
StreamWriter sw = new StreamWriter(datadirectory + Path.DirectorySeparatorChar + name);
WebRequest req = HttpWebRequest.Create(url);
WebResponse res = req.GetResponse();
StreamReader resstream = new StreamReader(res.GetResponseStream());
string data = resstream.ReadToEnd();
Regex regex = new Regex("href=\"([^\"]+)\"", RegexOptions.IgnoreCase);
if (regex.IsMatch(data))
{
MatchCollection matchs = regex.Matches(data);
for (int i = 0; i < matchs.Count; i++)
{
if (matchs[i].Groups[1].Value.ToString().Contains(".."))
continue;
if (matchs[i].Groups[1].Value.ToString().Contains("http"))
continue;
list.Add(url.TrimEnd(new char[] { '/', '\\' }) + "/" + matchs[i].Groups[1].Value.ToString());
}
}
list.ForEach(x =>
{
sw.WriteLine((string)x);
});
sw.Close();
}
catch { }
return list;
}
}
}