#!/usr/bin/env python
#
# Copyright 2018 Espressif Systems (Shanghai) PTE LTD
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

from __future__ import print_function
from builtins import range
from future.moves.itertools import zip_longest
import sys
import os
import csv
import argparse
import distutils.dir_util

try:
    sys.path.insert(0, os.getenv('IDF_PATH') + "/components/nvs_flash/nvs_partition_generator/")
    import nvs_partition_gen
except Exception as e:
    print(e)
    sys.exit("Please check IDF_PATH")


def verify_values_exist(input_values_file, keys_in_values_file):
    """ Verify all keys have corresponding values in values file
    """
    line_no = 1
    key_count_in_values_file = len(keys_in_values_file)

    values_file = open(input_values_file, 'r')
    values_file_reader = csv.reader(values_file, delimiter=',')
    next(values_file_reader)

    for values_data in values_file_reader:
        line_no += 1
        if len(values_data) != key_count_in_values_file:
            raise SystemExit("\nOops...Number of values is not equal to number of keys in file: %s at line No:%s\n"
                             % (str(input_values_file), str(line_no)))


def verify_keys_exist(values_file_keys, input_config_file):
    """ Verify all keys from config file are present in values file
    """
    keys_missing = []

    config_file = open(input_config_file,'r')
    config_file_reader = csv.reader(filter(lambda row: row[0] != '#',config_file), delimiter=',')
    for line_no, config_data in enumerate(config_file_reader,1):
        if 'namespace' not in config_data:
            if values_file_keys:
                if config_data[0] == values_file_keys[0]:
                    del values_file_keys[0]
                else:
                    keys_missing.append([config_data[0], line_no])
            else:
                keys_missing.append([config_data[0], line_no])

    if keys_missing:
        for key, line_no in keys_missing:
            print("Key:`", str(key), "` at line no:", str(line_no),
                  " in config file is not found in values file.")
        config_file.close()
        raise SystemExit(1)

    config_file.close()


def verify_datatype_encoding(input_config_file):
    """ Verify datatype and encodings from config file is valid
    """
    valid_encodings = ["string", "binary", "hex2bin","u8", "i8", "u16", "u32", "i32","base64"]
    valid_datatypes = ["file","data","namespace"]
    line_no = 0

    config_file = open(input_config_file,'r')
    config_file_reader = csv.reader(filter(lambda row: row[0] != '#',config_file), delimiter=',')
    for config_data in config_file_reader:
        line_no += 1
        if config_data[1] not in valid_datatypes:
            raise SystemExit("Oops...config file: %s has invalid datatype at line no:%s\n`"
                             % (str(input_config_file), str(line_no)))
        if 'namespace' not in config_data:
            if config_data[2] not in valid_encodings:
                raise SystemExit("Oops...config file: %s has invalid encoding at line no:%s\n`"
                                 % (str(input_config_file), str(line_no)))


def verify_file_data_count(input_config_file, keys_repeat):
    """ Verify count of data on each line in config file is equal to 3
    (as format must be: <key,type and encoding>)
    """
    line_no = 0
    config_file = open(input_config_file, 'r')
    config_file_reader = csv.reader(filter(lambda row: row[0] != '#',config_file), delimiter=',')
    for line in config_file_reader:
        line_no += 1
        if len(line) != 3 and line[0] not in keys_repeat:
            raise SystemExit("Oops...data missing in config file at line no:%s <format needed:key,type,encoding>\n"
                             % str(line_no))
    config_file.close()


def verify_data_in_file(input_config_file, input_values_file, config_file_keys, keys_in_values_file, keys_repeat):
    """ Verify count of data on each line in config file is equal to 3 \
    (as format must be: <key,type and encoding>)
    Verify datatype and encodings from config file is valid
    Verify all keys from config file are present in values file and \
    Verify each key has corresponding value in values file
    """
    try:
        values_file_keys = []

        verify_file_data_count(input_config_file, keys_repeat)

        verify_datatype_encoding(input_config_file)

        # Get keys from values file present in config files
        values_file_keys = get_keys(keys_in_values_file, config_file_keys)

        verify_keys_exist(values_file_keys, input_config_file)

        verify_values_exist(input_values_file, keys_in_values_file)

    except Exception as err:
        print(err)
        raise


def get_keys(keys_in_values_file, config_file_keys):
    """ Get keys from values file present in config file
    """
    values_file_keys = []
    for key in range(len(keys_in_values_file)):
        if keys_in_values_file[key] in config_file_keys:
            values_file_keys.append(keys_in_values_file[key])

    return values_file_keys


def add_config_data_per_namespace(input_config_file):
    """ Add config data per namespace to `config_data_to_write` list
    """
    config_data_to_write = []
    config_data_per_namespace = []

    csv_config_file = open(input_config_file,'r')
    config_file_reader = csv.reader(filter(lambda row: row[0] != '#',csv_config_file), delimiter=',')

    # `config_data_per_namespace` is added to `config_data_to_write` list after reading next namespace
    for config_data in config_file_reader:
        if 'REPEAT' in config_data:
            config_data.remove('REPEAT')
        if 'namespace' in config_data:
            if config_data_per_namespace:
                config_data_to_write.append(config_data_per_namespace)
                config_data_per_namespace = []
                config_data_per_namespace.append(config_data)
            else:
                config_data_per_namespace.append(config_data)
        else:
            config_data_per_namespace.append(config_data)

    # `config_data_per_namespace` is added to `config_data_to_write` list as EOF is reached
    if (not config_data_to_write) or (config_data_to_write and config_data_per_namespace):
        config_data_to_write.append(config_data_per_namespace)

    csv_config_file.close()

    return config_data_to_write


def get_fileid_val(file_identifier, keys_in_config_file, keys_in_values_file,
                   values_data_line, key_value_data, fileid_value):
    """ Get file identifier value
    """
    file_id_found = False

    for key in key_value_data:
        if file_identifier and not file_id_found and file_identifier in key:
            fileid_value = key[1]
            file_id_found = True

    if not file_id_found:
        fileid_value = str(int(fileid_value) + 1)

    return fileid_value


def add_data_to_file(config_data_to_write, key_value_pair, output_csv_file):
    """ Add data to csv target file
    """
    header = ['key', 'type', 'encoding', 'value']
    data_to_write = []

    target_csv_file = open(output_csv_file, 'w')

    output_file_writer = csv.writer(target_csv_file, delimiter=',')
    output_file_writer.writerow(header)

    for namespace_config_data in config_data_to_write:
        for data in namespace_config_data:
            data_to_write = data[:]
            if 'namespace' in data:
                data_to_write.append('')
                output_file_writer.writerow(data_to_write)
            else:
                key = data[0]
                while key not in key_value_pair[0]:
                    del key_value_pair[0]
                if key in key_value_pair[0]:
                    value = key_value_pair[0][1]
                    data_to_write.append(value)
                    del key_value_pair[0]
                    output_file_writer.writerow(data_to_write)

    # Set index to start of file
    target_csv_file.seek(0)

    target_csv_file.close()


def create_dir(filetype, output_dir_path):
    """ Create new directory(if doesn't exist) to store file generated
    """
    output_target_dir = output_dir_path + filetype
    if not os.path.isdir(output_target_dir):
        distutils.dir_util.mkpath(output_target_dir)

    return output_target_dir


def set_repeat_value(total_keys_repeat, keys, csv_file, target_filename):
    key_val_pair = []
    key_repeated = []
    with open(csv_file, 'r') as read_from, open(target_filename,'w') as write_to:
        csv_file_reader = csv.reader(read_from, delimiter=',')
        headers = next(csv_file_reader)
        values = next(csv_file_reader)
        csv_file_writer = csv.writer(write_to, delimiter=',')
        csv_file_writer.writerow(headers)
        csv_file_writer.writerow(values)
        total_keys_values = list(zip_longest(keys, values))

        # read new data, add value if key has repeat tag, write to new file
        for row in csv_file_reader:
            index = -1
            key_val_new = list(zip_longest(keys, row))
            key_val_pair = total_keys_values[:]
            key_repeated = total_keys_repeat[:]
            while key_val_new and key_repeated:
                index = index + 1
                #  if key has repeat tag, get its corresponding value, write to file
                if key_val_new[0][0] == key_repeated[0]:
                    val = key_val_pair[0][1]
                    row[index] = val
                    del key_repeated[0]
                del key_val_new[0]
                del key_val_pair[0]
            csv_file_writer.writerow(row)

    return target_filename


def main(input_config_file=None,input_values_file=None,target_file_name_prefix=None,
         file_identifier=None,output_dir_path=None,part_size=None,input_version=None,
         input_is_keygen=None,input_is_encrypt=None,input_is_keyfile=None):
    try:
        if all(arg is None for arg in [input_config_file,input_values_file,target_file_name_prefix,
                                       file_identifier,output_dir_path]):
            parser = argparse.ArgumentParser(prog='./mfg_gen.py',
                                             description="Create binary files from input config and values file",
                                             formatter_class=argparse.RawDescriptionHelpFormatter)

            parser.add_argument('--conf',
                                dest='config_file',
                                help='the input configuration csv file',
                                default=None)

            parser.add_argument('--values',
                                dest='values_file',
                                help='the input values csv file',
                                default=None)

            parser.add_argument('--prefix',
                                dest='prefix',
                                help='the unique name as each filename prefix')

            parser.add_argument('--fileid',
                                dest='fileid',
                                help='the unique file identifier(any key in values file) \
                                as each filename suffix (Default: numeric value(1,2,3...)')

            parser.add_argument('--outdir',
                                dest='outdir',
                                default=os.getcwd(),
                                help='the output directory to store the files created\
                                (Default: current directory)')

            parser.add_argument("--size",
                                dest='part_size',
                                help='Size of NVS Partition in bytes (must be multiple of 4096)')

            parser.add_argument("--version",
                                dest="version",
                                help='Set version. Default: v2',
                                choices=['v1','v2'],
                                default='v2',
                                type=str.lower)

            parser.add_argument("--keygen",
                                dest="keygen",
                                help='Generate keys for encryption. Default: false',
                                choices=['true','false'],
                                default='false',
                                type=str.lower)

            parser.add_argument("--encrypt",
                                dest="encrypt",
                                help='Set encryption mode. Default: false',
                                choices=['true','false'],
                                default='false',
                                type=str.lower)

            parser.add_argument("--keyfile",
                                dest="keyfile",
                                help='File having key for encryption (Applicable only if encryption mode is true)',
                                default=None)

            args = parser.parse_args()

            args.outdir = os.path.join(args.outdir, '')

            input_config_file = args.config_file
            input_values_file = args.values_file
            target_file_name_prefix = args.prefix
            output_dir_path = args.outdir
            part_size = args.part_size
            input_version = args.version
            input_is_keygen = args.keygen
            input_is_encrypt = args.encrypt
            input_is_keyfile = args.keyfile
            file_identifier = ''
            print_arg_str = "Invalid.\nTo generate binary --conf, --values, --prefix and --size arguments are mandatory.\
            \nTo generate encryption keys --keygen argument is mandatory."
            print_encrypt_arg_str = "Missing parameter. Enter --keygen or --keyfile."

            if args.fileid:
                file_identifier = args.fileid

            if input_config_file and input_is_encrypt.lower() == 'true' and input_is_keygen.lower() == 'true' and input_is_keyfile:
                sys.exit('Invalid. Cannot provide both --keygen and --keyfile argument together.')

            nvs_partition_gen.check_input_args(input_config_file, input_values_file, part_size, input_is_keygen,
                                               input_is_encrypt, input_is_keyfile, input_version, print_arg_str,
                                               print_encrypt_arg_str, output_dir_path)

            if not input_config_file and input_is_keygen:
                if input_is_encrypt == 'true':
                    sys.exit("Invalid.\nOnly --keyfile and --outdir arguments allowed.\n")
                # Generate Key Only
                nvs_partition_gen.nvs_part_gen(input_filename=input_config_file, output_filename=input_values_file,
                                               input_part_size=part_size, is_key_gen=input_is_keygen,
                                               encrypt_mode=input_is_encrypt, key_file=input_is_keyfile,
                                               version_no=input_version, output_dir=output_dir_path)
                exit(0)

            if not (input_config_file and input_values_file and target_file_name_prefix and part_size):
                sys.exit(print_arg_str)

        keys_in_values_file = []
        keys_in_config_file = []
        config_data_to_write = []
        key_value_data = []
        csv_file_list = []
        keys_repeat = []
        is_empty_line = False
        files_created = False
        file_identifier_value = '0'
        output_target_dir = ''
        target_values_file = None
        output_file_prefix = None

        # Verify config file is not empty
        if os.stat(input_config_file).st_size == 0:
            raise SystemExit("Oops...config file: %s is empty." % input_config_file)

        # Verify values file is not empty
        if os.stat(input_values_file).st_size == 0:
            raise SystemExit("Oops...values file: %s is empty." % input_values_file)

        # Verify config file does not have empty lines
        csv_config_file = open(input_config_file,'r')
        try:
            config_file_reader = csv.reader(csv_config_file, delimiter=',')
            for config_data in config_file_reader:
                for data in config_data:
                    empty_line = data.strip()
                    if empty_line is '':
                        is_empty_line = True
                    else:
                        is_empty_line = False
                        break
                if is_empty_line:
                    raise SystemExit("Oops...config file: %s cannot have empty lines. " % input_config_file)
                if not config_data:
                    raise SystemExit("Oops...config file: %s cannot have empty lines." % input_config_file)

            csv_config_file.seek(0)

            # Extract keys from config file
            for config_data in config_file_reader:
                if 'namespace' not in config_data:
                    keys_in_config_file.append(config_data[0])
                if 'REPEAT' in config_data:
                    keys_repeat.append(config_data[0])

            csv_config_file.close()
        except Exception as e:
            print(e)
        finally:
            csv_config_file.close()

        is_empty_line = False
        # Verify values file does not have empty lines
        csv_values_file = open(input_values_file, 'r')
        try:
            values_file_reader = csv.reader(csv_values_file, delimiter=',')
            for values_data in values_file_reader:
                for data in values_data:
                    empty_line = data.strip()
                    if empty_line is '':
                        is_empty_line = True
                    else:
                        is_empty_line = False
                        break
                if is_empty_line:
                    raise SystemExit("Oops...values file: %s cannot have empty lines." % input_values_file)
                if not values_data:
                    raise SystemExit("Oops...values file: %s cannot have empty lines." % input_values_file)

            csv_values_file.seek(0)

            # Extract keys from values file
            keys_in_values_file = next(values_file_reader)

            csv_values_file.close()
        except Exception as e:
            print(e)
            exit(1)
        finally:
            csv_values_file.close()

        # Verify file identifier exists in values file
        if file_identifier:
            if file_identifier not in keys_in_values_file:
                raise SystemExit('Oops...target_file_identifier: %s does not exist in values file.\n' % file_identifier)

        # Verify data in the input_config_file and input_values_file
        verify_data_in_file(input_config_file, input_values_file, keys_in_config_file,
                            keys_in_values_file, keys_repeat)

        # Add config data per namespace to `config_data_to_write` list
        config_data_to_write = add_config_data_per_namespace(input_config_file)

        try:
            with open(input_values_file, 'r') as csv_values_file:
                values_file_reader = csv.reader(csv_values_file, delimiter=',')
                keys = next(values_file_reader)

            filename, file_ext = os.path.splitext(input_values_file)
            target_filename = filename + "_created" + file_ext
            if keys_repeat:
                target_values_file = set_repeat_value(keys_repeat, keys, input_values_file, target_filename)
            else:
                target_values_file = input_values_file

            csv_values_file = open(target_values_file, 'r')

            values_file_reader = csv.reader(csv_values_file, delimiter=',')
            next(values_file_reader)
            for values_data_line in values_file_reader:
                key_value_data = list(zip_longest(keys_in_values_file,values_data_line))

                # Get file identifier value from values file
                file_identifier_value = get_fileid_val(file_identifier, keys_in_config_file,
                                                       keys_in_values_file, values_data_line, key_value_data, file_identifier_value)

                key_value_pair = key_value_data[:]

                # Create new directory(if doesn't exist) to store csv file generated
                output_target_dir = create_dir("csv/", output_dir_path)

                # Verify if output csv file does not exist
                csv_filename = target_file_name_prefix + "-" + file_identifier_value + ".csv"
                csv_file_list.append(csv_filename)
                output_csv_file = output_target_dir + csv_filename
                if os.path.isfile(output_csv_file):
                    raise SystemExit("Target csv file: %s already exists.`" % output_csv_file)

                # Add values corresponding to each key to csv target file
                add_data_to_file(config_data_to_write, key_value_pair, output_csv_file)

                # Create new directory(if doesn't exist) to store bin file generated
                output_target_dir = create_dir("bin/", output_dir_path)

                # Verify if output bin file does not exist
                output_file_prefix = target_file_name_prefix + "-" + file_identifier_value
                output_bin_file = output_target_dir + output_file_prefix + ".bin"
                if os.path.isfile(output_bin_file):
                    raise SystemExit("Target csv file: %s already exists.`" % output_bin_file)

                # Create output csv and bin file
                if input_is_keygen.lower() == 'true' and input_is_keyfile:
                    input_is_keyfile = os.path.basename(input_is_keyfile)
                nvs_partition_gen.nvs_part_gen(input_filename=output_csv_file, output_filename=output_bin_file,
                                               input_part_size=part_size, is_key_gen=input_is_keygen,
                                               encrypt_mode=input_is_encrypt, key_file=input_is_keyfile,
                                               version_no=input_version, encr_key_prefix=output_file_prefix, output_dir=output_dir_path)
                print("CSV Generated: ", str(output_csv_file))

                files_created = True

            csv_values_file.close()
        except Exception as e:
            print(e)
            exit(1)
        finally:
            csv_values_file.close()
        return csv_file_list, files_created, target_values_file

    except ValueError as err:
        print(err)
    except Exception:
        raise


if __name__ == "__main__":
    main()