#-------------------------------------------------------------------------------
# Name:        DuchampParameterGUI_fileIO
# Purpose:
#
# Author:      Kelvin
#
# Created:     4/12/2013
#-------------------------------------------------------------------------------

import os

# Determine the current directory.
directory = os.getcwd()

# Define the default file path.
defaultParamFileName = '/InputComplete'
defaultParamFilePath = directory + defaultParamFileName


# This reads parameter files with the specified format.
def readParamFile(paramFilePath):

    # Create a dictionary that maps parameter names to its value and a list to keep track of its order.
    parameters = {}
    orderedParameters = []

    try:
        # Open the given parameter file.
        paramFile = open(paramFilePath)

        # Load files for lines of parameter data in the specified format and
        # store them into the dictionary.
        for line in paramFile:
            if line[0] != '#' and len(line.split()) > 1:
                linebits = line.split()
                parameters[linebits[0]] = linebits[1]
                orderedParameters = orderedParameters + [linebits[0]]

        paramFile.close()

    # Note that if the file could not be read, then the dictionary will stay empty.
    # The GUI window can make use of this fact.
    except IOError:
        print("Cannot open file")

    return(parameters, orderedParameters)


# This reads the default file for all relevant information of parameter classes, description, type, and format.
def readParamByClass(paramFilePath):

    # Create a diciontary that maps parameter names to its class and a list to keep track of class orders.
    classOfParameter = {}
    classNames = []

    # Create dictionaries that maps parameter names to its description, value type, and value format.
    description = {}
    paramType = {}
    paramFormat = {}

    try:
        # Open the given parameter file.
        paramFile = open(paramFilePath)

        # Load files for lines of parameter data in the specified format and
        # store them into the dictionaries.
        for line in paramFile:

            if line[0:3] == '###' and len(line.split('###')) > 1:
                className = line.strip('###').strip()
                classNames = classNames + [className]

            elif line[0:2] == '#*' and len(line.split()) > 1 and '--' in line:
                param = line.split()[1].strip()
                paramType[param] = line.split('[')[1].split(']')[0].strip()
                paramFormat[param] = line.split('{')[1].split('}')[0].strip()
                description[param] = '--'.join(line.split('--')[1:len(line.split('--'))]).strip()
                
            elif line[0] != '#' and len(line.split()) > 1:
                linebits = line.split()
                classOfParameter[linebits[0]] = className

        paramFile.close()

    # Note that if the file could not be read, then the dictionary will stay empty.
    # The GUI window can make use of this fact.
    except IOError:
        print("Cannot open file")
                 
    return(classOfParameter, classNames, description, paramType, paramFormat)


# Define a function to create a parameter file with the specified format.
# It will return 0 if the file already exists and will not overwrite the file just yet (unless write = 1)
#                1 if the file is successfully created (or overwriten)
#               -1 if the file was not successfully created (or overwriten) due to some error
def writeParamFile(newParamFilePath, parameters, parameterOrder, write):

    # If we want to make sure if it is okay to write, do the following.
    if write != 1:
        
        # First, try opening the file for reading.
        # If the file exists for reading, then close it and then return a 0,
        # which the GUI window use to warn the user that a file with that name already exists.
        try:
            newParamFile = open(newParamFilePath)
            newParamFile.close()
            return(0)

        # If we have trouble reading the file, then the file doesn't exist and we're safe to write to it.
        except IOError:
            write = 1

    # If we are sure we can write to the file, then do it.
    if write == 1:

        try:
            newParamFile = open(newParamFilePath, 'w')
            
            # Write the editted set of parameters into the new file.
            for par in parameterOrder:
                newParamFile.write('%s    %s\n'%(par, parameters[par]))

            newParamFile.close()
            return(1)
        
        except IOError:
            return(-1)