#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Thu Jan 21 11:49:12 2021

@author: Jérémy Bernard, University of Gothenburg
"""

#!/usr/bin/python
from __future__ import print_function
import os
import urllib3
from . import DataUtil
from .GlobalVariables import INSTANCE_NAME, INSTANCE_ID, INSTANCE_PASS, NEW_DB,\
    JAVA_PATH_FILENAME, TEMPO_DIRECTORY
import subprocess
import re
import pandas as pd

try:
    #path_pybin = DataUtil.locate_py()
    #subprocess.check_call([str(path_pybin), "-m", "pip", "install", "jaydebeapi"])
    import jaydebeapi
except ImportError:
    #print("'jaydebeapi' Python package is missing, cannot connect to H2 Driver")
    #exit(1)
    exit("'jaydebeapi' Python package is missing")
# Global variables
# H2GIS_VERSION = "1.5.0"
# H2GIS_URL = H2GIS_VERSION.join(["https://github.com/orbisgis/h2gis/releases/download/v",
#                                 "/h2gis-dist-",
#                                 "-bin.zip"])
# H2GIS_UNZIPPED_NAME = "h2gis-standalone"+os.sep+"h2gis-dist-"+H2GIS_VERSION+".jar"

H2GIS_VERSION = "2.2.4-SNAPSHOT"
H2GIS_URL = "https://nightly.link/orbisgis/h2gis/workflows/CI_snapshot/master/h2gis-standalone-bin.zip"
H2GIS_UNZIPPED_NAME = "h2gis-standalone"+os.sep+"h2gis-dist-"+H2GIS_VERSION+".jar"

JAVA_PATH_POSIX = [os.path.join(os.sep, "usr", "lib", "jvm")]
JAVA_PATH_NT = [os.path.join("C:", os.sep, "Program Files", "Java"), os.path.join("C:", os.sep, "Program Files", "OpenJDK"),
		        os.path.join("C:", os.sep, "Program Files (x86)", "Java"), os.path.join("C:", os.sep, "Program Files (x86)", "OpenJDK")]

# DB extension
DB_EXTENSION = ".mv.db"
DB_TRACE_EXTENSION = ".trace.db"

def downloadH2gis(dbDirectory):
    """ Download the H2GIS spatial database management system (used for Röckle zone calculation)
        For more information about use with Python: https://github.com/orbisgis/h2gis/wiki/4.4-Use-H2GIS-with-Python

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

			dbDirectory: String
				Directory where shoud be stored the H2GIS jar            
            
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            None"""
    # Get the zip file name and create the local file directory
    zipFileName = H2GIS_URL.split("/")[-1]
    localH2ZipDir = (dbDirectory+os.sep+zipFileName).encode('utf-8')
    localH2JarDir = (dbDirectory+os.sep+H2GIS_UNZIPPED_NAME).encode('utf-8')
    
    # Test whether the .jar already downloaded
    if(os.path.exists(localH2ZipDir) or os.path.exists(localH2JarDir)):
        print("H2GIS version %s already downloaded" % (H2GIS_VERSION))
    else:
        print("Downloading H2GIS version %s at %s..." % (H2GIS_URL, H2GIS_VERSION))
        # Download the archive file and save it into the 'dbDirectory'
        http = urllib3.PoolManager()
        r = http.request('GET', url = H2GIS_URL, preload_content=False)  
        with open(localH2ZipDir, 'wb') as out:
            while True:
                data = r.read(2**16)
                if not data:
                    break
                out.write(data)
        r.release_conn()
        print("H2GIS version %s downloaded !!" % (H2GIS_VERSION))
    
    # Test whether the .jar already exists
    if(os.path.exists(localH2JarDir)):
        print("H2GIS version %s already unzipped" % (H2GIS_VERSION))
    else:
        print("Unzipping H2GIS version %s..." % (H2GIS_VERSION))
        # Unzip the H2GIS archive
        print(dbDirectory)
        print(zipFileName)
        DataUtil.decompressZip(dbDirectory, zipFileName)
        print("H2GIS version %s unzipped !!" % (H2GIS_VERSION))

           
def startH2gisInstance(dbDirectory, dbInstanceDir = TEMPO_DIRECTORY, 
                       instanceName = INSTANCE_NAME, suffix = "", 
                       instanceId=INSTANCE_ID, 
                       instancePass = INSTANCE_PASS):
    """ Start an H2GIS spatial database instance (used for Röckle zone calculation)
    For more information about use with Python: https://github.com/orbisgis/h2gis/wiki/4.4-Use-H2GIS-with-Python

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

			dbDirectory: String
				Directory where is stored the H2GIS jar         
            dbInstanceDir: String
                Directory where should be started the H2GIS instance
            instanceName: String, default INSTANCE_NAME
                File name used for the database
            suffix: String, default ""
                Suffix to add at the end of the database name
            instanceId: String, default INSTANCE_ID
                ID used to connect to the database
            instancePass: String, default INSTANCE_PASS
                password used to connect to the database
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            cur: conn.cursor
                A cursor object, used to perform queries
            conn: 
                A connection object to the database
            localH2InstanceDir: String
                File directory of the database to delete (without extension)"""    
    # Define where are the jar of the DB and the H2GIS instance (in absolute paths)
    localH2JarDir = dbDirectory+os.sep+H2GIS_UNZIPPED_NAME
    localH2InstanceDir = dbInstanceDir+os.sep+instanceName + suffix

    isDbExist = os.path.exists(localH2InstanceDir+DB_EXTENSION)
    
    # print the connection string we will use to connect
    print("Connecting to database\n	->%s" % (localH2InstanceDir))
    print (localH2JarDir)

    # If the DB already exists and if 'newDB' is set to True, delete all the DB files
    if isDbExist:
        os.remove(localH2InstanceDir+DB_EXTENSION)
        if os.path.exists(localH2InstanceDir+DB_TRACE_EXTENSION):
            os.remove(localH2InstanceDir+DB_TRACE_EXTENSION)
    
    # get a connection, if a connect cannot be made an exception will be raised here
    conn = jaydebeapi.connect(  "org.h2.Driver",
                                "jdbc:h2:"+localH2InstanceDir+";AUTO_SERVER=TRUE;",
                                [instanceId, instancePass],
                                localH2JarDir,)

    # conn.cursor will return a cursor object, you can use this cursor to perform queries
    cur = conn.cursor()
    print("Connected!\n")
    

    # Init spatial features
    cur.execute("CREATE ALIAS IF NOT EXISTS H2GIS_SPATIAL FOR \"org.h2gis.functions.factory.H2GISFunctions.load\";")
    cur.execute("CALL H2GIS_SPATIAL();")
    print("Spatial functions added!\n")
    
    return cur, conn, localH2InstanceDir

def closeAndRemoveH2gisInstance(localH2InstanceDir, conn, cur):
    """ Close an H2GIS instance and remove the database file

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

            localH2InstanceDir: String
                File directory of the database to delete (without extension)
            conn: 
                A connection object to the database
            cur: conn.cursor
                A cursor object, used to perform queries
            
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            None"""
    # Close cursor and connection and then delete the H2GIS database file
    cur.close()
    conn.close()
    if os.path.exists(localH2InstanceDir + DB_EXTENSION):
        os.remove(localH2InstanceDir + DB_EXTENSION)
    if os.path.exists(localH2InstanceDir + DB_TRACE_EXTENSION):
        os.remove(localH2InstanceDir + DB_TRACE_EXTENSION)

def setJavaDir(javaPath):
    """ If there is no JAVA variable environment set or neither already one 
    saved in the URock repository, ask the user to enter one for
    local use

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

            javaPath: String
                JAVA variable path
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            None"""
    os.environ.setdefault("JAVA_HOME", javaPath)
        
def getJavaDir(pluginDirectory):
    """ Try to get the JAVA variable environment if already set.
    Otherwise try to get it from the user plugin repository.
    Otherwise try to set from the OS type

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

            plugin_directory: String
                Path of the plugin directory where could be saved the java path
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            javaPath: String
                JAVA variable path"""
    javaPath = os.environ.get("JAVA_HOME")
    javaPathFile = os.path.join(pluginDirectory, JAVA_PATH_FILENAME)
    # For some reason, JAVA_HOME may be set to %JAVA_HOME% while there is no
    # Java home set. This should be associated to None
    if javaPath:
        if javaPath[0] == "%":
            javaPath == None
    if not javaPath:
        if os.path.exists(javaPathFile):
            javaFilePath = open(javaPathFile, "r")
            javaPath = javaFilePath.read()
            javaFilePath.close()
        else:
            os_type = os.name
            javaPath = getJavaHome(os_type)
            # if os_type == "posix":
            #     javaPath = identifyJavaDir(JAVA_PATH_POSIX)
            # else:
            #     javaPath = identifyJavaDir(JAVA_PATH_NT)
 
    return javaPath

def saveJavaDir(javaPath, pluginDirectory):
    """ Save the java path into a file in the user plugin repository

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

            javaPath: String
                JAVA variable path
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            None"""
    javaPathFile = os.path.join(pluginDirectory, JAVA_PATH_FILENAME)
    if not os.path.exists(pluginDirectory):
        os.makedirs(pluginDirectory)
    if os.path.exists(javaPathFile):
        existingJavaFilePath = open(javaPathFile, "r", encoding='utf8')
        existingJavaPath = existingJavaFilePath.read()
        existingJavaFilePath.close()
    else:
        existingJavaPath = None
    if (existingJavaPath != javaPath) or existingJavaPath is None:
        if os.path.exists(javaPathFile):
            os.remove(javaPathFile)
        javaFilePath = open(javaPathFile, "w", encoding='utf8')
        javaFilePath.write(javaPath)
        javaFilePath.close()

def identifyJavaDir(java_path_os_list):
    """ Try to get the directory where is located the last Java version in the OS...

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

            java_path_os_list: list of String
                Possible locations of the Java directory
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            javaPath: String
                JAVA variable path"""
    JavaExists = False
    i = 0
    # Test some common folder paths to check whether a Java installation exists and stops once found
    while(not (JavaExists or i >= len(java_path_os_list))):
        javaBaseDir = java_path_os_list[i]
        JavaExists = os.path.exists(javaBaseDir)
        i += 1
    if JavaExists:
        listJavaVersion = os.listdir(javaBaseDir)
        listSplit = pd.Series()
        for i, v in enumerate(listJavaVersion):
            tempo_split = re.split('\.|\-', v)
            # Previous command supposed to split version number based on usual characters. 
            # If unusual need the following...
            if len(tempo_split) != 3:
                pattern = re.compile(r'java|jdk|jre1')
                jvm_match = pattern.search(v).group(0)
                tempo_split = re.split('{0}|u'.format(jvm_match), v)
                tempo_split[0] = jvm_match
            listSplit.loc[i] = tempo_split

        df_version = pd.DataFrame({"version": [listSplit[i][1] \
                                                for i in listSplit.index],
                                    "startWith": [listSplit[i][0] \
                                                    for i in listSplit.index]})
        highestVersion = df_version[(df_version.startWith == "java")\
                                     | (df_version.startWith == "jdk")\
                                     | (df_version.startWith == "jre1")\
                                     | (df_version.startWith == "jre")].version.astype(int).idxmax()
        javaPath = os.path.join(javaBaseDir, listJavaVersion[highestVersion])
    else:
        javaPath = None
    
    return javaPath

def getJavaHome(os_type):
    """ Try to get the Java home path of the machine if Java installed...
    Inspired from https://www.baeldung.com/find-java-home

		Parameters
		_ _ _ _ _ _ _ _ _ _ 

            os_type: String
                Type of OS (POSIX or NT)
        
		Returns
		_ _ _ _ _ _ _ _ _ _ 

            javaPath: String
                JAVA variable path"""
    # Within a subprocess calling Java, get the line corresponding to java_home
    if os_type == "posix":
        command = "java -XshowSettings:properties -version 2>&1 > /dev/null | grep 'java.home'"
        proc = subprocess.Popen(['bash', '-c', command], 
                                stdout=subprocess.PIPE, stderr=subprocess.PIPE,
                                stdin=subprocess.PIPE)
        output, err = proc.communicate()
        # Identify the string corresponding to the java_home in the resulting line
        javaPath = os.path.abspath(str(output).split("java.home = ")[1].split("\\n")[0])
    
    else:
        import winreg

        try:
            java_key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, r"SOFTWARE\JavaSoft\Java Runtime Environment")

        except FileNotFoundError:
            try:
                java_key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, r"SOFTWARE\JavaSoft\JRE")
            except FileNotFoundError:
                try:
                    java_key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, r"SOFTWARE\JavaSoft\Java Development Kit")
                except FileNotFoundError:
                    try:
                        java_key = winreg.OpenKey(winreg.HKEY_LOCAL_MACHINE, r"SOFTWARE\JavaSoft\JDK")
                    except:
                        print("Java not found")
                        exit()

        current_version, _ = winreg.QueryValueEx(java_key, "CurrentVersion")
        java_version_key = winreg.OpenKey(java_key, current_version)
        javaPath, _ = winreg.QueryValueEx(java_version_key, "JavaHome")
        
    return javaPath