# imports
# function to test
from __future__ import absolute_import

import re
from decimal import Decimal
from functools import partial

import pytest  # used for our unit tests
from parse import Parser

PARSE_RE = re.compile(r"({{|}}|{[\w-]*(?:\.[\w-]+|\[[^]]+])*(?::[^}]+)?})")

REGEX_SAFETY = re.compile(r"([?\\.[\]()*+^$!|])")

# unit tests
@pytest.mark.parametrize("format_string, expected", [
    # Basic Format Strings
    ("Hello World", r"Hello World"),
    ("Sample text with no fields", r"Sample text with no fields"),
    ("{{}}", r"\{\}"),
    ("{{Hello}}", r"\{Hello\}"),
    ("{name}", r"(?P<name>.+?)"),
    ("{0}", r"(.+?)"),
    ("{name} {age}", r"(?P<name>.+?) (?P<age>.+?)"),
    ("{0} {1}", r"(.+?) (.+?)"),

    # Fields with Format Specifiers
    ("{value:d}", r"(?P<value>\d+)"),
    ("{value:.2f}", r"(?P<value>\d*\.\d+)"),
    ("{value:x}", r"(?P<value>(0[xX])?[0-9a-fA-F]+)"),
    ("{name:s}", r"(?P<name>.+?)"),
    ("{name:20s}", r"(?P<name>.+?)"),
    ("{date:%Y-%m-%d}", r"(?P<date>.+?)"),
    ("{time:%H:%M:%S}", r"(?P<time>.+?)"),

    # Edge Cases
    ("", r""),
    ("{name", r"\{name"),
    ("name}", r"name\}"),
    ("{outer{inner}}", r"\{outer(?P<inner>.+?)\}"),

    # Complex Format Strings
    ("Name: {name}, Age: {age}, Score: {score:.2f}", r"Name: (?P<name>.+?), Age: (?P<age>.+?), Score: (?P<score>\d*\.\d+)"),
    ("Date: {date:%Y-%m-%d}, Time: {time:%H:%M:%S}", r"Date: (?P<date>.+?), Time: (?P<time>.+?)"),
    ("{name} {name}", r"(?P<name>.+?) (?P=name)"),
    ("{0} {0}", r"(.+?) \1"),
    ("{user-name}", r"(?P<user_name>.+?)"),
    ("{user.name}", r"(?P<user__name>.+?)"),

    # Performance and Scalability
    (" ".join(f"{{field{i}}}" for i in range(1000)), r" ".join(f"(?P<field{i}>.+?)" for i in range(1000))),

    # Case Sensitivity
    ("{Name}", r"(?P<Name>.+?)"),
    ("{name}", r"(?P<name>.+?)"),

    # Extra Types
    ("{custom_field:custom_type}", r"(?P<custom_field>.+?)"),

    # Special Characters in Text
    ("Text with special characters: .+*?^$()[]{}", r"Text with special characters: \.\+\*\?\^\$\(\)\[\]\{\}"),
    ("Escaped characters: \\ \\.", r"Escaped characters: \\\\ \\\\."),

    # Alignment and Padding
    ("{name:<10}", r"(?P<name>.+?) *"),
    ("{name:>10}", r" *(.+?)"),
    ("{name:^10}", r" *(.+?) *"),
    ("{name:*>10}", r"\**(.+?)"),
    ("{name:_<10}", r"(?P<name>.+?)_*"),

    # Numeric Specifics
    ("{value:+d}", r"[-+ ]?\d+"),
    ("{value: d}", r"[-+ ]?\d+"),
    ("{value:0=10d}", r"0*\d+"),

    # Rare or Unexpected Edge Cases
    ("{name!me}", r"\{name!me\}"),
    ("{na@me}", r"\{na@me\}"),
    ("{name with spaces}", r"\{name with spaces\}"),
    ("{value:10z}", r"(?P<value>\%z+)"),
    ("{value:10q}", r"(?P<value>\%q+)"),
    ("{outer{inner}}", r"\{outer(?P<inner>.+?)\}"),
    ("{outer{{inner}}}", r"\{outer\{inner\}\}"),
    ("{user-name}", r"(?P<user_name>.+?)"),
    ("{user.name}", r"(?P<user__name>.+?)"),
    ("{}", r"(.+?)"),
    ("{ }", r"(?P< >.+?)"),
    ("{{{name}}", r"\{\{(?P<name>.+?)\}"),
    ("{name}}}", r"(?P<name>.+?)\}"),
    ("{value:!@#}", r"(?P<value>\%#)"),
    ("{value:10.2!}", r"(?P<value>\%!)"),
    ("{value:*>10}", r"\**(.+?)"),
    ("{value:_<10}", r"(?P<value>.+?)_*"),
    ("{value:-10d}", r"(?P<value>\d+)"),
    ("{value:0d}", r"(?P<value>\d+)"),
    ("{date:%Q-%W-%E}", r"(?P<date>.+?)"),
    ("{date:%Y-%m}", r"(?P<date>.+?)"),
    ("{outer{inner{deep}}}", r"\{outer(?P<inner>.+?)\{deep\}\}"),
    ("{json_field:{'key':'value'}}", r"\{json_field:\{'key':'value'\}\}"),
    ("{名前}", r"(?P<名前>.+?)"),
    ("{用户}", r"(?P<用户>.+?)"),
    ("{name\\n}", r"\{name\\n\}"),
    ("{name\\t}", r"\{name\\t\}")
])
def test_generate_expression(format_string, expected):
    parser = Parser(format_string)
    codeflash_output = parser._generate_expression()
    # Outputs were verified to be equal to the original implementation