# -*- coding: utf-8 -*-
"""
/***************************************************************************
 Qgis2threejs
                                 A QGIS plugin
 export terrain and map image into web browser
                              -------------------
        begin                : 2013-12-29
        copyright            : (C) 2013 Minoru Akagi
        email                : akaginch@gmail.com
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
"""
from PyQt4.QtCore import qDebug, QProcess, QSettings, QUrl, QByteArray, QBuffer, QIODevice, QFile, QDir, QFileInfo
from PyQt4.QtGui import QMessageBox
import sys
import os
import ConfigParser
import shutil
import struct
import base64
import webbrowser

try:
  from osgeo import gdal
except ImportError:
  import gdal

from gdal2threejs import Raster

debug_mode = 1

class MemoryWarpRaster(Raster):
  def __init__(self, filename):
    Raster.__init__(self, filename)
    self.driver = gdal.GetDriverByName("MEM")

  def read(self, width, height, wkt, geotransform):
    # create a memory dataset
    warped_ds = self.driver.Create("", width, height, 1, gdal.GDT_Float32)
    warped_ds.SetProjection(wkt)
    warped_ds.SetGeoTransform(geotransform)

    # reproject image
    gdal.ReprojectImage(self.ds, warped_ds, None, None, gdal.GRA_Bilinear)

    # load values into an array
    values = []
    fs = "f" * width
    band = warped_ds.GetRasterBand(1)
    for py in range(height):
      values += struct.unpack(fs, band.ReadRaster(0, py, width, 1, width, 1, gdal.GDT_Float32))
    return values

  def readValue(self, wkt, x, y):
    # get value at the position using 1px * 1px memory raster
    res = 0.1
    geotransform = [x - res / 2, res, 0, y + res / 2, 0, -res]
    return self.read(1, 1, wkt, geotransform)[0]

class FlatRaster:
  def __init__(self, value=0):
    self.value = value

  def read(self, width, height, wkt, geotransform):
    return [self.value] * width * height

  def readValue(self, wkt, x, y):
    return self.value

def warpDEM(layer, crs, extent, width, height, multiplier):
  # calculate extent. output dem should be handled as points.
  xres = extent.width() / (width - 1)
  yres = extent.height() / (height - 1)
  geotransform = [extent.xMinimum() - xres / 2, xres, 0, extent.yMaximum() + yres / 2, 0, -yres]
  wkt = str(crs.toWkt())

  if debug_mode:
    qDebug("warpDEM: %d x %d, extent %s" % (width, height, str(geotransform)))

  warped_dem = MemoryWarpRaster(layer.source().encode("UTF-8"))
  values = warped_dem.read(width, height, wkt, geotransform)
  warped_dem.close()
  if multiplier != 1:
    values = map(lambda x: x * multiplier, values)
  return values

def generateDEM(layer, crs, extent, width, height, demfilename):
  # generate dem file
  # gdalwarp options
  options = []
  options.append("--config GDAL_FILENAME_IS_UTF8 NO")
  options.append("-r bilinear")

  # calculate extent. note: pixel is area in the output geotiff, but pixel should be handled as point
  xres = extent.width() / width
  yres = extent.height() / height
  ext = (extent.xMinimum() - xres / 2, extent.yMinimum() - yres / 2, extent.xMaximum() + xres / 2, extent.yMaximum() + yres / 2)
  options.append("-te %f %f %f %f" % ext)
  options.append("-ts %d %d" % (width + 1, height + 1))

  # target crs
  authid = crs.authid()
  if authid.startswith("EPSG:"):
    options.append("-t_srs %s" % authid)
  else:
    options.append('-t_srs "%s"' % crs.toProj4())

  options.append('"' + layer.source() + '"')
  options.append('"' + demfilename + '"')

  # run gdalwarp command
  cmd = "gdalwarp " + u" ".join(options)
  if debug_mode:
    qDebug(cmd.encode("UTF-8"))
  process = QProcess()
  process.start(cmd)
  process.waitForFinished()
  if not os.path.exists(demfilename):
    hint = ""
    if os.system("gdalwarp --help-general"):
      hint = "gdalwarp is not installed."
    return "Failed to generate a dem file using gdalwarp. " + hint
  return 0

def openHTMLFile(htmlfilename):
  settings = QSettings()
  browserPath = settings.value("/Qgis2threejs/browser", "", type=unicode)
  if browserPath == "":
    # open default web browser
    webbrowser.open(htmlfilename, new=2)    # new=2: new tab if possible
  else:
    if not QProcess.startDetached(browserPath, [QUrl.fromLocalFile(htmlfilename).toString()]):
      QMessageBox.warning(None, "Qgis2threejs", "Cannot open browser: %s\nSet correct path in settings dialog." % browserPath)
      return False
  return True

def base64image(image):
  ba = QByteArray()
  buffer = QBuffer(ba)
  buffer.open(QIODevice.WriteOnly)
  image.save(buffer, "PNG")
  return "data:image/png;base64," + base64.b64encode(ba)

def getTemplateMetadata(template_path):
  meta_path = os.path.splitext(template_path)[0] + ".txt"
  if not os.path.exists(meta_path):
    return {}
  parser = ConfigParser.SafeConfigParser()
  with open(meta_path, "r") as f:
    parser.readfp(f)
  metadata = {}
  for item in parser.items("general"):
    metadata[item[0]] = item[1]
  if debug_mode:
    qDebug("metadata: " + str(metadata))
  return metadata

def copyFile(source, dest, overwrite=False):
  if os.path.exists(dest):
    if overwrite or abs(QFileInfo(source).lastModified().secsTo(QFileInfo(dest).lastModified())) > 5:   # use secsTo for different file systems
      if debug_mode:
        qDebug("Existing file removed: %s (%s, %s)" % (dest, str(QFileInfo(source).lastModified()), str(QFileInfo(dest).lastModified())))
      QFile.remove(dest)
    else:
      if debug_mode:
        qDebug("File already exists: %s" % dest)
      return False

  if debug_mode:
    qDebug("File copied: %s to %s" % (source, dest))
  return QFile.copy(source, dest)

def copyLibraries(out_dir, metadata, overwrite=False):
  plugin_dir = pluginDir()
  files = metadata.get("files", "").strip()
  if files:
    for f in files.split(","):
      filename = os.path.basename(f)
      copyFile(os.path.join(plugin_dir, f), os.path.join(out_dir, filename), overwrite)

  dirs = metadata.get("dirs", "").strip()
  if dirs:
    for d in dirs.split(","):
      dirpath = os.path.join(plugin_dir, d)
      dirname = os.path.basename(d)
      target = os.path.join(out_dir, dirname)
      if overwrite or not os.path.exists(target):
        if debug_mode:
          qDebug("Copy dir: %s to %s" % (dirpath, target))
        shutil.copytree(dirpath, target)
      #TODO: message if already exists

def copyThreejsFiles(out_dir, controls, overwrite=False):
  threejs_dir = pluginDir() + "/js/threejs"

  # make directory
  target_dir = os.path.join(out_dir, "threejs")
  QDir().mkpath(target_dir)

  # copy files in threejs directory
  filenames = QDir(threejs_dir).entryList(QDir.Files)
  for filename in filenames:
    copyFile(os.path.join(threejs_dir, filename), os.path.join(target_dir, filename), overwrite)

  # copy controls file
  copyFile(os.path.join(threejs_dir, "controls", controls), os.path.join(target_dir, controls), overwrite)

def removeTemporaryFiles(filelist):
  for file in filelist:
    QFile.remove(file)

def removeTemporaryOutputDir():
  removeDir(temporaryOutputDir())

def removeDir(dirName):
  d = QDir(dirName)
  if d.exists():
    for info in d.entryInfoList(QDir.Dirs | QDir.Files | QDir.NoDotAndDotDot):
      if info.isDir():
        removeDir(info.absoluteFilePath())
      else:
        d.remove(info.fileName())
    d.rmdir(dirName)

def pluginDir():
  return os.path.dirname(QFile.decodeName(__file__))

def templateDir():
  return os.path.join(pluginDir(), "html_templates")

def temporaryOutputDir():
  return QDir.tempPath() + "/Qgis2threejs"