#
# Copyright 2004-2006,2008-2009 Zuza Software Foundation
#
# This file is part of the Translate Toolkit.
#
# 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.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <http://www.gnu.org/licenses/>.

"""
Classes that hold units of .rc files (:class:`rcunit`) or entire files
(:class:`rcfile`) used in translating Windows Resources.

.. note:::

   This implementation is based mostly on observing WINE .rc files,
   these should mimic other non-WINE .rc files.
"""

import re

from pyparsing import (
    AtLineStart,
    Combine,
    Forward,
    Group,
    Keyword,
    OneOrMore,
    Optional,
    Word,
    ZeroOrMore,
    alphanums,
    alphas,
    c_style_comment,
    delimited_list,
    nums,
    printables,
    quoted_string,
    rest_of_line,
)
from pyparsing.common import pyparsing_common

from translate.storage import base


def escape_to_python(string):
    """Unescape a given .rc string into a valid Python string."""
    return (
        re.sub(r'"\s*\\\n\s*"', "", string)  # xxx"\n"xxx line continuation
        .replace("\\\n", "")  # backslash newline line continuation
        .replace(r"\r", "\r")
        .replace(r"\n", "\n")
        .replace(r"\t", "\t")
        .replace(r"\\", "\\")
        .replace('""', '"')
    )


def extract_text(values):
    result = []
    for value in values:
        if isinstance(value, str) and value.startswith('"'):
            result.append(escape_to_python(value[1:-1]))
        else:
            break
    return "".join(result)


def extract_id(values):
    for value in values:
        if isinstance(value, str) and value.startswith('"'):
            continue
        if isinstance(value, str):
            return value
        break

    return "UNKNOWN_ID"


def escape_to_rc(string):
    """Escape a given Python string into a valid .rc string."""
    return (
        string.replace("\\", r"\\")
        .replace("\t", r"\t")
        .replace("\n", r"\n")
        .replace("\r", r"\r")
        .replace('"', '""')
    )


class rcunit(base.TranslationUnit):
    """A unit of an rc file."""

    def __init__(self, source="", **kwargs):
        """Construct a blank rcunit."""
        super().__init__(source)
        self.name = ""
        self._value = ""
        self.comments = []
        self.source = source
        self.match = None

    @property
    def source(self):
        return self._value

    @source.setter
    def source(self, source):
        """Sets the source AND the target to be equal."""
        self._rich_source = None
        self._value = source or ""

    @property
    def target(self):
        return self.source

    @target.setter
    def target(self, target):
        """.. note:: This also sets the ``.source`` attribute!."""
        self._rich_target = None
        self.source = target

    def __str__(self):
        """Convert to a string."""
        return self.getoutput()

    def getoutput(self):
        """Convert the element back into formatted lines for a .rc file."""
        if self.isblank():
            return "".join([*self.comments, "\n"])
        return "".join([*self.comments, f"{self.name}={self._value}\n"])

    def getlocations(self):
        return [self.name]

    def addnote(self, text, origin=None, position="append"):
        self.comments.append(text)

    def getnotes(self, origin=None):
        return "\n".join(self.comments)

    def removenotes(self, origin=None):
        self.comments = []

    def isblank(self):
        """Returns whether this is a blank element, containing only comments."""
        return not (self.name or self.value)


def rc_statement():
    """
    Generate a RC statement parser that can be used to parse a RC file.

    :rtype: pyparsing.ParserElement
    """
    one_line_comment = Combine("//" + rest_of_line)

    comments = c_style_comment ^ one_line_comment

    precompiler = AtLineStart(Word("#", alphanums) + rest_of_line)

    language_definition = (
        "LANGUAGE"
        + Word(alphas + "_").set_results_name("language")
        + Optional("," + Word(alphas + "_").set_results_name("sublanguage"))
    )

    block_start = (Keyword("{") | Keyword("BEGIN")).set_name("block_start")
    block_end = (Keyword("}") | Keyword("END")).set_name("block_end")

    numbers = Word(nums)

    integerconstant = numbers ^ Combine("0x" + numbers)

    name_id = Group(Word(alphas, alphanums + "_") | integerconstant)

    constant = Combine(
        Optional(Keyword("NOT")) + Group(name_id),
        adjacent=False,
        join_string=" ",
    )

    combined_constants = delimited_list(constant, "|", min=2)

    concatenated_string = OneOrMore(quoted_string)

    caption = "CAPTION" + quoted_string("caption")

    block_options = ZeroOrMore(
        Group(caption ^ language_definition ^ quoted_string ^ Word(printables)),
        stop_on=block_start,
    )("block_options")

    undefined_control = (
        Group(
            name_id.set_results_name("id_control")
            + Optional(",")
            + delimited_list(
                concatenated_string ^ constant ^ numbers ^ Group(combined_constants)
            ).set_results_name("values_")
        )
        | comments
    )

    block = (
        block_start
        + ZeroOrMore(undefined_control, stop_on=block_end)("controls")
        + block_end
    )

    dialog = (
        name_id("block_id")
        + (Keyword("DIALOGEX") | Keyword("DIALOG"))("block_type")
        + block_options
        + block
    )

    string_table = Keyword("STRINGTABLE")("block_type") + block_options + block

    menu_item = Keyword("MENUITEM")("block_type") + (
        pyparsing_common.comma_separated_list("values_") | Keyword("SEPARATOR")
    )

    popup_block = Forward()

    popup_block <<= Group(
        Keyword("POPUP")("block_type")
        + Optional(quoted_string("caption"))
        + Optional(
            ","
            + delimited_list(
                concatenated_string ^ constant ^ numbers ^ Group(combined_constants)
            ).set_results_name("values_")
        )
        + block_start
        + ZeroOrMore(Group(menu_item | popup_block | comments), stop_on=block_end)(
            "elements"
        )
        + block_end
    )("popups*")

    menu = (
        name_id("block_id")
        + (Keyword("MENU") | Keyword("MENUEX"))("block_type")
        + block_options
        + block_start
        + ZeroOrMore(popup_block | comments, stop_on=block_end)
        + block_end
    )

    return comments ^ precompiler ^ dialog ^ string_table ^ menu ^ language_definition


def generate_stringtable_name(identifier):
    """Return the name generated for a stringtable element."""
    return f"STRINGTABLE.{identifier}"


def generate_menu_pre_name(block_type, block_id):
    """Return the pre-name generated for elements of a menu."""
    return f"{block_type}.{block_id}"


def generate_popup_pre_name(pre_name, caption):
    """
    Return the pre-name generated for subelements of a popup.

    :param pre_name: The pre_name that already have the popup.
    :param caption: The caption (without quotes) of the popup.

    :return: The subelements pre-name based in the pre-name of the popup and
             its caption.
    """
    return "{}.{}".format(pre_name, caption.replace(" ", "_"))


def generate_popup_caption_name(pre_name):
    """Return the name generated for a caption of a popup."""
    return f"{pre_name}.POPUP.CAPTION"


def generate_menuitem_name(pre_name, block_type, identifier):
    """Return the name generated for a menuitem of a popup."""
    return f"{pre_name}.{block_type}.{identifier}"


def generate_dialog_caption_name(block_type, identifier):
    """Return the name generated for a caption of a dialog."""
    return f"{block_type}.{identifier}.CAPTION"


def generate_dialog_control_name(block_type, block_id, control_type, identifier):
    """Return the name generated for a control of a dialog."""
    return f"{block_type}.{block_id}.{control_type}.{identifier}"


def parse_encoding_pragma(pragma):
    pragma = pragma.strip()
    codepage = pragma.split("(")[1].split(")")[0].strip()
    if codepage == "65001":
        return "utf-8"
    if len(codepage) == 4:
        return f"cp{codepage}"
    return None


class rcfile(base.TranslationStore):
    """This class represents a .rc file, made up of rcunits."""

    UnitClass = rcunit
    default_encoding = "cp1252"

    def __init__(
        self, inputfile=None, lang=None, sublang=None, encoding=None, **kwargs
    ):
        """Construct an rcfile, optionally reading in from inputfile."""
        super().__init__(encoding=encoding, **kwargs)
        self.filename = getattr(inputfile, "name", "")
        self.lang = lang
        self.sublang = sublang
        self.newline = "\r\n"
        if inputfile is not None:
            rcsrc = inputfile.read()
            inputfile.close()
            self.parse(
                rcsrc,
                encoding=encoding or "auto",
            )

    def add_popup_units(self, pre_name, popup):
        """Transverses the popup tree making new units as needed."""
        if popup.caption:
            newunit = rcunit(escape_to_python(popup.caption[1:-1]))
            newunit.name = generate_popup_caption_name(pre_name)
            newunit.match = popup
            self.addunit(newunit)

        for element in popup.elements:
            if element.block_type and element.block_type == "MENUITEM":
                if element.values_ and len(element.values_) >= 2:
                    newtext = extract_text(element.values_)
                    if newtext:
                        newunit = rcunit(newtext)
                        newunit.name = generate_menuitem_name(
                            pre_name, element.block_type, extract_id(element.values_)
                        )
                        newunit.match = element
                        self.addunit(newunit)
                # Else it can be a separator.
            elif element.popups:
                for sub_popup in element.popups:
                    self.add_popup_units(
                        generate_popup_pre_name(pre_name, popup.caption[1:-1]),
                        sub_popup,
                    )

    def parse(self, rcsrc, encoding="auto"):
        """Read the source of a .rc file in and include them as units."""
        self.encoding = encoding
        if encoding != "auto":
            decoded = rcsrc.decode(encoding)
        elif b"\000" in rcsrc[:2]:
            self.encoding = "utf-16-le"
            decoded = rcsrc.decode(self.encoding)
        else:
            decoded, self.encoding = self.detect_encoding(
                rcsrc, default_encodings=[self.default_encoding]
            )

        # Extract first newline
        for line in decoded.splitlines(True):
            if len(line) >= 2 and line[-2] in {"\r", "\n"}:
                self.newline = line[-2:]
            else:
                self.newline = line[-1]
            break

        decoded = decoded.replace("\r", "")

        # Parse the strings into a structure.
        results = rc_statement().search_string(decoded)

        processblocks = True

        for statement in results:
            # Parse pragma
            if (
                statement[0] == "#pragma"
                and "code_page" in statement[1]
                and self.encoding not in {"utf-8", "utf-16"}
            ):
                expected_encoding = parse_encoding_pragma(statement[1])
                if expected_encoding and expected_encoding != self.encoding:
                    self.units = []
                    self.parse(rcsrc, expected_encoding)
                    return
            if statement.language:
                if self.lang is None or statement.language == self.lang:
                    if self.sublang is None or statement.sublanguage == self.sublang:
                        self.lang = statement.language
                        self.sublang = statement.sublanguage
                        processblocks = True
                    else:
                        processblocks = False
                else:
                    processblocks = False
                continue

            if processblocks and statement.block_type:
                if statement.block_type in {"DIALOG", "DIALOGEX"}:
                    for option in statement.block_options:
                        if option.caption:
                            newunit = rcunit(escape_to_python(option.caption[1:-1]))
                            newunit.name = generate_dialog_caption_name(
                                statement.block_type, statement.block_id[0]
                            )
                            newunit.match = option
                            self.addunit(newunit)

                    for control in statement.controls:
                        if isinstance(control, str):
                            # This is a comment
                            continue
                        if control.id_control[0] in {
                            "AUTOCHECKBOX",
                            "AUTORADIOBUTTON",
                            "CAPTION",
                            "CHECKBOX",
                            "CTEXT",
                            "CONTROL",
                            "DEFPUSHBUTTON",
                            "GROUPBOX",
                            "LTEXT",
                            "PUSHBUTTON",
                            "RADIOBUTTON",
                            "RTEXT",
                        } and (
                            control.values_[0].startswith('"')
                            or control.values_[0].startswith("'")
                        ):
                            # The first value without quoted chars.
                            newtext = extract_text(control.values_)
                            if newtext:
                                newunit = rcunit(newtext)
                                newunit.name = generate_dialog_control_name(
                                    statement.block_type,
                                    statement.block_id[0],
                                    control.id_control[0],
                                    extract_id(control.values_),
                                )
                                newunit.match = control
                                self.addunit(newunit)

                    continue

                if statement.block_type in {"MENU", "MENUEX"}:
                    pre_name = generate_menu_pre_name(
                        statement.block_type, statement.block_id[0]
                    )

                    for popup in statement.popups:
                        self.add_popup_units(pre_name, popup)

                    continue

                if statement.block_type in ("STRINGTABLE"):
                    for text in statement.controls:
                        if isinstance(text, str):
                            # This is a comment
                            continue

                        newtext = extract_text(text.values_)
                        if newtext:
                            newunit = rcunit(newtext)
                            newunit.name = generate_stringtable_name(text.id_control[0])
                            newunit.match = text
                            self.addunit(newunit)

                    continue

    def serialize(self, out):
        """Write the units back to file."""
        out.write(("".join(self.blocks)).encode(self.encoding))
