#!/usr/bin/env python3

import argparse
import os
import shutil
from collections import OrderedDict

EXTRACT_TAGS = ["description", "brief_description", "member", "constant", "theme_item", "link"]
HEADER = """\
# LANGUAGE translation of the Godot Engine class reference.
# Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.
# Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).
# This file is distributed under the same license as the Godot source code.
#
# FIRST AUTHOR <EMAIL@ADDRESS>, YEAR.
#
#, fuzzy
msgid ""
msgstr ""
"Project-Id-Version: Godot Engine class reference\\n"
"Report-Msgid-Bugs-To: https://github.com/godotengine/godot\\n"
"MIME-Version: 1.0\\n"
"Content-Type: text/plain; charset=UTF-8\\n"
"Content-Transfer-Encoding: 8-bit\\n"

"""
# Some strings used by make_rst.py are normally part of the editor translations,
# so we need to include them manually here for the online docs.
BASE_STRINGS = [
    "Description",
    "Tutorials",
    "Properties",
    "Methods",
    "Theme Properties",
    "Signals",
    "Enumerations",
    "Constants",
    "Property Descriptions",
    "Method Descriptions",
    "Theme Property Descriptions",
    "Inherits:",
    "Inherited By:",
    "(overrides %s)",
    "Default",
    "Setter",
    "value",
    "Getter",
    "This method should typically be overridden by the user to have any effect.",
    "This method has no side effects. It doesn't modify any of the instance's member variables.",
    "This method accepts any number of arguments after the ones described here.",
    "This method is used to construct a type.",
    "This method doesn't need an instance to be called, so it can be called directly using the class name.",
    "This method describes a valid operator to use with this type as left-hand operand.",
]

## <xml-line-number-hack from="https://stackoverflow.com/a/36430270/10846399">
import sys

sys.modules["_elementtree"] = None
import xml.etree.ElementTree as ET

## override the parser to get the line number
class LineNumberingParser(ET.XMLParser):
    def _start(self, *args, **kwargs):
        ## Here we assume the default XML parser which is expat
        ## and copy its element position attributes into output Elements
        element = super(self.__class__, self)._start(*args, **kwargs)
        element._start_line_number = self.parser.CurrentLineNumber
        element._start_column_number = self.parser.CurrentColumnNumber
        element._start_byte_index = self.parser.CurrentByteIndex
        return element

    def _end(self, *args, **kwargs):
        element = super(self.__class__, self)._end(*args, **kwargs)
        element._end_line_number = self.parser.CurrentLineNumber
        element._end_column_number = self.parser.CurrentColumnNumber
        element._end_byte_index = self.parser.CurrentByteIndex
        return element


## </xml-line-number-hack>


class Desc:
    def __init__(self, line_no, msg, desc_list=None):
        ## line_no   : the line number where the desc is
        ## msg       : the description string
        ## desc_list : the DescList it belongs to
        self.line_no = line_no
        self.msg = msg
        self.desc_list = desc_list


class DescList:
    def __init__(self, doc, path):
        ## doc  : root xml element of the document
        ## path : file path of the xml document
        ## list : list of Desc objects for this document
        self.doc = doc
        self.path = path
        self.list = []


def print_error(error):
    print("ERROR: {}".format(error))


## build classes with xml elements recursively
def _collect_classes_dir(path, classes):
    if not os.path.isdir(path):
        print_error("Invalid directory path: {}".format(path))
        exit(1)
    for _dir in map(lambda dir: os.path.join(path, dir), os.listdir(path)):
        if os.path.isdir(_dir):
            _collect_classes_dir(_dir, classes)
        elif os.path.isfile(_dir):
            if not _dir.endswith(".xml"):
                # print("Got non-.xml file '{}', skipping.".format(path))
                continue
            _collect_classes_file(_dir, classes)


## opens a file and parse xml add to classes
def _collect_classes_file(path, classes):
    if not os.path.isfile(path) or not path.endswith(".xml"):
        print_error("Invalid xml file path: {}".format(path))
        exit(1)
    print("Collecting file: {}".format(os.path.basename(path)))

    try:
        tree = ET.parse(path, parser=LineNumberingParser())
    except ET.ParseError as e:
        print_error("Parse error reading file '{}': {}".format(path, e))
        exit(1)

    doc = tree.getroot()

    if "name" in doc.attrib:
        if "version" not in doc.attrib:
            print_error("Version missing from 'doc', file: {}".format(path))

        name = doc.attrib["name"]
        if name in classes:
            print_error("Duplicate class {} at path {}".format(name, path))
            exit(1)
        classes[name] = DescList(doc, path)
    else:
        print_error("Unknown XML file {}, skipping".format(path))


## regions are list of tuples with size 3 (start_index, end_index, indent)
## indication in string where the codeblock starts, ends, and it's indent
## if i inside the region returns the indent, else returns -1
def _get_xml_indent(i, regions):
    for region in regions:
        if region[0] < i < region[1]:
            return region[2]
    return -1


## find and build all regions of codeblock which we need later
def _make_codeblock_regions(desc, path=""):
    code_block_end = False
    code_block_index = 0
    code_block_regions = []
    while not code_block_end:
        code_block_index = desc.find("[codeblock]", code_block_index)
        if code_block_index < 0:
            break
        xml_indent = 0
        while True:
            ## [codeblock] always have a trailing new line and some tabs
            ## those tabs are belongs to xml indentations not code indent
            if desc[code_block_index + len("[codeblock]\n") + xml_indent] == "\t":
                xml_indent += 1
            else:
                break
        end_index = desc.find("[/codeblock]", code_block_index)
        if end_index < 0:
            print_error("Non terminating codeblock: {}".format(path))
            exit(1)
        code_block_regions.append((code_block_index, end_index, xml_indent))
        code_block_index += 1
    return code_block_regions


def _strip_and_split_desc(desc, code_block_regions):
    desc_strip = ""  ## a stripped desc msg
    total_indent = 0  ## code indent = total indent - xml indent
    for i in range(len(desc)):
        c = desc[i]
        if c == "\n":
            c = "\\n"
        if c == '"':
            c = '\\"'
        if c == "\\":
            c = "\\\\"  ## <element \> is invalid for msgmerge
        if c == "\t":
            xml_indent = _get_xml_indent(i, code_block_regions)
            if xml_indent >= 0:
                total_indent += 1
                if xml_indent < total_indent:
                    c = "\\t"
                else:
                    continue
            else:
                continue
        desc_strip += c
        if c == "\\n":
            total_indent = 0
    return desc_strip


## make catalog strings from xml elements
def _make_translation_catalog(classes):
    unique_msgs = OrderedDict()
    for class_name in classes:
        desc_list = classes[class_name]
        for elem in desc_list.doc.iter():
            if elem.tag in EXTRACT_TAGS:
                if not elem.text or len(elem.text) == 0:
                    continue
                line_no = elem._start_line_number if elem.text[0] != "\n" else elem._start_line_number + 1
                desc_str = elem.text.strip()
                code_block_regions = _make_codeblock_regions(desc_str, desc_list.path)
                desc_msg = _strip_and_split_desc(desc_str, code_block_regions)
                desc_obj = Desc(line_no, desc_msg, desc_list)
                desc_list.list.append(desc_obj)

                if desc_msg not in unique_msgs:
                    unique_msgs[desc_msg] = [desc_obj]
                else:
                    unique_msgs[desc_msg].append(desc_obj)
    return unique_msgs


## generate the catalog file
def _generate_translation_catalog_file(unique_msgs, output, location_line=False):
    with open(output, "w", encoding="utf8") as f:
        f.write(HEADER)
        for msg in BASE_STRINGS:
            f.write("#: doc/tools/make_rst.py\n")
            f.write('msgid "{}"\n'.format(msg))
            f.write('msgstr ""\n\n')
        for msg in unique_msgs:
            if len(msg) == 0 or msg in BASE_STRINGS:
                continue

            f.write("#:")
            desc_list = unique_msgs[msg]
            for desc in desc_list:
                path = desc.desc_list.path.replace("\\", "/")
                if path.startswith("./"):
                    path = path[2:]
                if location_line:  # Can be skipped as diffs on line numbers are spammy.
                    f.write(" {}:{}".format(path, desc.line_no))
                else:
                    f.write(" {}".format(path))
            f.write("\n")

            f.write('msgid "{}"\n'.format(msg))
            f.write('msgstr ""\n\n')

    ## TODO: what if 'nt'?
    if os.name == "posix":
        print("Wrapping template at 79 characters for compatibility with Weblate.")
        os.system("msgmerge -w79 {0} {0} > {0}.wrap".format(output))
        shutil.move("{}.wrap".format(output), output)


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument(
        "--path", "-p", nargs="+", default=".", help="The directory or directories containing XML files to collect."
    )
    parser.add_argument("--output", "-o", default="translation_catalog.pot", help="The path to the output file.")
    args = parser.parse_args()

    output = os.path.abspath(args.output)
    if not os.path.isdir(os.path.dirname(output)) or not output.endswith(".pot"):
        print_error("Invalid output path: {}".format(output))
        exit(1)

    classes = OrderedDict()
    for path in args.path:
        if not os.path.isdir(path):
            print_error("Invalid working directory path: {}".format(path))
            exit(1)

        print("\nCurrent working dir: {}".format(path))

        path_classes = OrderedDict()  ## dictionary of key=class_name, value=DescList objects
        _collect_classes_dir(path, path_classes)
        classes.update(path_classes)

    classes = OrderedDict(sorted(classes.items(), key=lambda kv: kv[0].lower()))
    unique_msgs = _make_translation_catalog(classes)
    _generate_translation_catalog_file(unique_msgs, output)


if __name__ == "__main__":
    main()