import re

from modgen.parserbase.parser import FileParser

EVENT_ENTRY_NAME_IDX = 0
EVENT_ENTRY_SEVERITY_IDX = 1
EVENT_ENTRY_INFO_IDX = 2
EVENT_SOURCE_FILE_IDX = 3
FSFW_EVENT_HEADER_INCLUDE = "#include <fsfw/events/Event.h>"
DEFAULT_MOVING_WINDOWS_SIZE = 7
SUBSYSTEM_ID_NAMESPACE = "SUBSYSTEM_ID"

EVENT_NAME_IDX = 1


class SubsystemDefinitionParser(FileParser):
    def __init__(self, file_list):
        super().__init__(file_list)
        self.moving_window_center_idx = 3

    def _handle_file_parsing(self, file_name: str, *args, **kwargs):
        file = open(file_name, "r")
        for line in file.readlines():
            match = re.search(r'([A-Z0-9_]*) = ([0-9]{1,3})', line)
            if match:
                self.mib_table.update({match.group(1): [match.group(2)]})

    def _handle_file_parsing_moving_window(
            self, file_name: str, current_line: int, moving_window_size: int, moving_window: list,
            *args, **kwargs):
        match = re.search(r'([A-Z0-9_]*) = ([0-9]{1,3})', moving_window[self.moving_window_center_idx])
        if match:
            self.mib_table.update({match.group(1): [match.group(2)]})

    def _post_parsing_operation(self):
        pass


class EventParser(FileParser):
    def __init__(self, file_list, interface_list):
        super().__init__(file_list)
        self.interfaces = interface_list
        self.count = 0
        self.my_id = 0
        self.current_id = 0
        self.last_lines = ["", "", ""]
        self.moving_window_center_idx = 3

    def _handle_file_parsing(self, file_name: str, *args: any, **kwargs):
        try:
            file = open(file_name, 'r', encoding='utf-8')
            all_lines = file.readlines()
        except UnicodeDecodeError:
            file = open(file_name, 'r', encoding='cp1252')
            all_lines = file.readlines()
        total_count = 0
        for line in all_lines:
            self.__handle_line_reading(line, file_name)
        if self.count > 0:
            print("File " + file_name + " contained " + str(self.count) + " events.")
            total_count += self.count
            self.count = 0

    def _handle_file_parsing_moving_window(
            self, file_name: str, current_line: int, moving_window_size: int, moving_window: list,
            *args, **kwargs):
        subsystem_id_assignment_match = re.search(
            rf"([\w]*)[\s]*=[\s]*{SUBSYSTEM_ID_NAMESPACE}::([A-Z_0-9]*);", moving_window[self.moving_window_center_idx]
        )
        if subsystem_id_assignment_match:
            # For now, it is assumed that there is only going to be one subsystem ID per class / source file
            # if "SUBSYSTEM_ID" in subsystem_id_assignment_match.group(1):
            try:
                self.current_id = self.interfaces[subsystem_id_assignment_match.group(2)][0]
                self.my_id = self.return_number_from_string(self.current_id)
            except KeyError as e:
                print(f"Key not found: {e}")

        # Now try to look for event definitions. Moving windows allows multi line event definitions
        # These two variants need to be checked
        event_match = re.match(
            r"[\s]*static const(?:expr)?[\s]*Event[\s]*([\w]*)[\s]*=[\s]*event::makeEvent[^\n]*",
            moving_window[self.moving_window_center_idx]
        )
        macro_api_match = False
        if not event_match:
            event_match = re.match(
                r"[\s]*static[\s]*const(?:expr)?[\s]*Event[\s]*([\w]*)[\s]*=[\s]*MAKE_EVENT[^\n]*",
                moving_window[self.moving_window_center_idx]
            )
            if event_match:
                macro_api_match = True
        if event_match:
            self.__handle_event_match(
                event_match=event_match, macro_api_match=macro_api_match, moving_window=moving_window,
                file_name=file_name
            )

    def __handle_event_match(self, event_match, macro_api_match: bool, moving_window: list, file_name: str):
        event_full_match = False
        if ";" in event_match.group(0):
            event_full_match = self.__handle_one_line_event_match(
                macro_api_match=macro_api_match, moving_window=moving_window
            )
        # Description will be parsed separately later
        description = " "
        if event_full_match:
            name = event_match.group(EVENT_NAME_IDX)
            if macro_api_match:
                full_id = (self.my_id * 100) + self.return_number_from_string(event_full_match.group(2))
                severity = event_full_match.group(3)
            else:
                full_id = (self.my_id * 100) + self.return_number_from_string(event_full_match.group(3))
                severity = event_full_match.group(4)
            self.mib_table.update({full_id: (name, severity, description, file_name)})
            self.count = self.count + 1

    def __handle_one_line_event_match(self, macro_api_match: bool, moving_window: list):
        if macro_api_match:
            # One line event definition.
            regex_string = \
                r"static const(?:expr)? Event[\s]*([\w]*)[\s]*=[\s]*" \
                r"MAKE_EVENT\(([0-9]{1,3}),[\s]*severity::([A-Z]*)\)[\s]*;"
        else:
            regex_string = \
                r"static const(?:expr)? Event[\s]*([\w]*)[\s]*=[\s]*" \
                r"event::makeEvent\(([\w]*),[\s]*([0-9]{1,3})[\s]*,[\s]*severity::([A-Z]*)\)[\s]*;"
        event_full_match = re.search(regex_string, moving_window[self.moving_window_center_idx])
        return event_full_match

    def _post_parsing_operation(self):
        pass

    def __handle_line_reading(self, line, file_name):
        if not self.last_lines[0] == '\n':
            twolines = self.last_lines[0] + ' ' + line.strip()
        else:
            twolines = ''
        match1 = re.search(r"SUBSYSTEM_ID[\s]*=[\s]*SUBSYSTEM_ID::([A-Z_0-9]*);", twolines)
        if match1:
            self.current_id = self.interfaces[match1.group(1)][0]
            # print( "Current ID: " + str(currentId) )
            self.my_id = self.return_number_from_string(self.current_id)
        match = re.search(
            r"(//)?[\t ]*static const(?:expr)? Event[\s]*([A-Z_0-9]*)[\s]*=[\s]*"
            r"MAKE_EVENT\(([0-9]{1,2}),[\s]*severity::([A-Z]*)\);[\t ]*(//!<)?([^\n]*)", twolines
        )
        if match:
            if match.group(1):
                self.last_lines[0] = line
                return
            description = " "
            if match.group(6):
                description = self.clean_up_description(match.group(6))
            string_to_add = match.group(2)
            full_id = (self.my_id * 100) + self.return_number_from_string(match.group(3))
            severity = match.group(4)
            if full_id in self.mib_table:
                # print("EventParser: Duplicate Event " + hex(full_id) + " from " + file_name +
                #      " was already in " + self.mib_table[full_id][3])
                pass
            self.mib_table.update({full_id: (string_to_add, severity, description, file_name)})
            self.count = self.count + 1
        self.last_lines[0] = line

    def build_checked_string(self, first_part, second_part):
        my_str = first_part + self.convert(second_part)
        if len(my_str) > 16:
            print(f"EventParser: Entry: {my_str} too long. Will truncate.")
            my_str = my_str[0:14]
        # else:
        # print( "Entry: " + myStr + " is all right.")
        return my_str

    @staticmethod
    def return_number_from_string(a_string):
        if a_string.startswith('0x'):
            return int(a_string, 16)
        elif a_string.isdigit():
            return int(a_string)
        else:
            print('EventParser: Illegal number representation: ' + a_string)
            return 0

    @staticmethod
    def convert(name):
        single_strings = name.split('_')
        new_string = ''
        for one_string in single_strings:
            one_string = one_string.lower()
            one_string = one_string.capitalize()
            new_string = new_string + one_string
        return new_string

    @staticmethod
    def clean_up_description(description):
        description = description.lstrip('//!<>')
        description = description.lstrip()
        if description == '':
            description = ' '
        return description


def export_to_file(filename: str, event_list: list, file_separator: str):
    file = open(filename, "w")
    for entry in event_list:
        event_id = entry[0]
        event_value = entry[1]
        file.write(
            str(event_id) + file_separator + event_value[EVENT_ENTRY_NAME_IDX] + file_separator +
            event_value[EVENT_ENTRY_SEVERITY_IDX] + file_separator + event_value[EVENT_ENTRY_INFO_IDX] +
            file_separator + event_value[EVENT_SOURCE_FILE_IDX] + '\n'
        )
    file.close()
    return


def write_translation_source_file(event_list: list, date_string: str, filename: str = "translateEvents.cpp"):
    outputfile = open(filename, "w")
    definitions = ""

    function = "const char * translateEvents(Event event) {\n\tswitch( (event & 0xffff) ) {\n"
    for entry in event_list:
        event_id = entry[0]
        event_value = entry[1]
        definitions += \
            f"const char *{event_value[EVENT_ENTRY_NAME_IDX]}_STRING = \"{event_value[EVENT_ENTRY_NAME_IDX]}\";\n"
        function += f"\tcase({event_id}):\n\t\treturn {event_value[EVENT_ENTRY_NAME_IDX]}_STRING;\n"
    function += '\tdefault:\n\t\treturn "UNKNOWN_EVENT";\n'
    outputfile.write(
        f"/**\n * @brief    Auto-generated event translation file. Contains {len(event_list)} translations.\n"
        f" * @details\n"
        f" * Generated on: {date_string}\n */\n"
    )
    outputfile.write("#include \"translateEvents.h\"\n\n")
    outputfile.write(definitions + "\n" + function + "\t}\n\treturn 0;\n}\n")
    outputfile.close()


def write_translation_header_file(filename: str = "translateEvents.h"):
    file = open(filename, "w")
    file.write(
        f"#ifndef FSFWCONFIG_EVENTS_TRANSLATEEVENTS_H_\n"
        f"#define FSFWCONFIG_EVENTS_TRANSLATEEVENTS_H_\n\n"
        f"{FSFW_EVENT_HEADER_INCLUDE}\n\n"
        f"const char * translateEvents(Event event);\n\n"
        f"#endif /* FSFWCONFIG_EVENTS_TRANSLATEEVENTS_H_ */\n"
    )


def handle_csv_export(file_name: str, event_list: list, file_separator: str):
    """
    Generates the CSV in the same directory as the .py file and copes the CSV to another
    directory if specified.
    """
    print("EventParser: Exporting to file: " + file_name)
    export_to_file(filename=file_name, event_list=event_list, file_separator=file_separator)


def handle_cpp_export(
        event_list: list, date_string: str, file_name: str = "translateEvents.cpp", generate_header: bool = True,
        header_file_name: str = "translateEvents.h"
):
    print("EventParser: Generating translation cpp file.")
    write_translation_source_file(event_list=event_list, date_string=date_string, filename=file_name)
    if generate_header:
        write_translation_header_file(filename=header_file_name)