"""
Source and credits: https://github.com/ZubinGou/math-evaluation-harness/blob/main/python_executor.py
"""
import re
import regex
import sympy
from typing import TypeVar, Iterable, List, Union, Any, Dict
from word2number import w2n
from utils import *


def lower_keys(example):  
    new_example = {}  
    for key, value in example.items():  
        if key != key.lower():  
            new_key = key.lower()  
            new_example[new_key] = value  
        else:  
            new_example[key] = value  
    return new_example 


def _fix_fracs(string):
    substrs = string.split("\\frac")
    new_str = substrs[0]
    if len(substrs) > 1:
        substrs = substrs[1:]
        for substr in substrs:
            new_str += "\\frac"
            if len(substr) > 0 and substr[0] == "{":
                new_str += substr
            else:
                try:
                    assert len(substr) >= 2
                except:
                    return string
                a = substr[0]
                b = substr[1]
                if b != "{":
                    if len(substr) > 2:
                        post_substr = substr[2:]
                        new_str += "{" + a + "}{" + b + "}" + post_substr
                    else:
                        new_str += "{" + a + "}{" + b + "}"
                else:
                    if len(substr) > 2:
                        post_substr = substr[2:]
                        new_str += "{" + a + "}" + b + post_substr
                    else:
                        new_str += "{" + a + "}" + b
    string = new_str
    return string


def _fix_a_slash_b(string):
    if len(string.split("/")) != 2:
        return string
    a = string.split("/")[0]
    b = string.split("/")[1]
    try:
        if "sqrt" not in a:
            a = int(a)
        if "sqrt" not in b:
            b = int(b)
        assert string == "{}/{}".format(a, b)
        new_string = "\\frac{" + str(a) + "}{" + str(b) + "}"
        return new_string
    except:
        return string


def _fix_sqrt(string):
    _string = re.sub(r"\\sqrt(\w+)", r"\\sqrt{\1}", string)
    return _string


def convert_word_number(text:str) -> str:
    try:
        text = str(w2n.word_to_num(text))
    except:
        pass
    return text

# units mainly from MathQA
unit_texts = [
    "east", "degree", "mph", "kmph", "ft", "m sqaure", " m east", "sq m", "deg", "mile",
    "q .", "monkey", "prime", "ratio", "profit of rs",  "rd", "o", "gm",
    "p . m", "lb", "tile", "per", "dm", "lt", "gain", "ab", "way", "west",
    "a .", "b .", "c .", "d .", "e .", "f .", "g .", "h .", "t", "a", "h",
    "no change", "men", "soldier", "pie", "bc", "excess", "st",
    "inches", "noon", "percent", "by", "gal", "kmh", "c", "acre", "rise",
    "a . m", "th", "π r 2", "sq", "mark", "l", "toy", "coin",
    "sq . m", "gallon", "° f", "profit", "minw", "yr", "women",
    "feet", "am", "pm", "hr", "cu cm", "square", "v â € ™", "are",
    "rupee", "rounds", "cubic", "cc", "mtr", "s", "ohm", "number",
    "kmph", "day", "hour", "minute", "min", "second", "man", "woman", 
    "sec", "cube", "mt", "sq inch", "mp", "∏ cm ³", "hectare", "more",
    "sec", "unit", "cu . m", "cm 2", "rs .", "rs", "kg", "g", "month",
    "km", "m", "cm", "mm", "apple", "liter", "loss", "yard",
    "pure", "year", "increase", "decrease", "d", "less", "Surface",
    "litre", "pi sq m", "s .", "metre", "meter", "inch",
]

unit_texts.extend([t + "s" for t in unit_texts])

def strip_string(string):
    string = str(string).strip()
    # linebreaks
    string = string.replace("\n", "")

    # right "."
    string = string.rstrip(".")

    # remove inverse spaces
    # replace \\ with \
    string = string.replace("\\!", "")
    # string = string.replace("\\ ", "")
    # string = string.replace("\\\\", "\\")

    # matrix
    string = re.sub(r'\\begin\{array\}\{.*?\}', r'\\begin{pmatrix}', string)  
    string = re.sub(r'\\end\{array\}', r'\\end{pmatrix}', string)  
    string = string.replace("bmatrix", "pmatrix")


    # replace tfrac and dfrac with frac
    string = string.replace("tfrac", "frac")
    string = string.replace("dfrac", "frac")

    # remove \left and \right
    string = string.replace("\\left", "")
    string = string.replace("\\right", "")
    string = string.replace("\\{", "{")
    string = string.replace("\\}", "}")

    # Remove unit: miles, dollars if after is not none
    _string = re.sub(r"\\text{.*?}$", "", string).strip()
    if _string != "" and _string != string:
        # print("Warning: unit not removed: '{}' -> '{}'".format(string, _string))
        string = _string
    
    # Remove unit: texts
    for _ in range(2):
        for unit_text in unit_texts:
            # use regex, the prefix should be either the start of the string or a non-alphanumeric character
            # the suffix should be either the end of the string or a non-alphanumeric character
            _string = re.sub(r"(^|\W)" + unit_text + r"($|\W)", r"\1\2", string)
            if _string != "":
                string = _string

    # Remove circ (degrees)
    string = string.replace("^{\\circ}", "")
    string = string.replace("^\\circ", "")

    # remove dollar signs
    string = string.replace("\\$", "")
    string = string.replace("$", "")

    # convert word number to digit
    string = convert_word_number(string)

    # replace "\\text{...}" to "..."
    string = re.sub(r"\\text\{(.*?)\}", r"\1", string)
    for key in ['x=', 'y=', 'z=', 'x\\in', 'y\\in', 'z\\in', 'x\\to', 'y\\to', 'z\\to']:
        string = string.replace(key, "")
    string = string.replace("\\emptyset", r"{}")
    string = string.replace("(-\\infty,\\infty)", "\\mathbb{R}")

    # remove percentage
    string = string.replace("\\%", "")
    string = string.replace("\%", "")
    string = string.replace("%", "")

    # " 0." equivalent to " ." and "{0." equivalent to "{." Alternatively, add "0" if "." is the start of the string
    string = string.replace(" .", " 0.")
    string = string.replace("{.", "{0.")

    # cdot
    # string = string.replace("\\cdot", "")
    if string.startswith("{") and string.endswith("}") and string.isalnum() or \
        string.startswith("(") and string.endswith(")") and string.isalnum() or \
        string.startswith("[") and string.endswith("]") and string.isalnum():
        string = string[1:-1]

    # inf
    string = string.replace("infinity", "\\infty")
    if "\\infty" not in string:
        string = string.replace("inf", "\\infty")
    string = string.replace("+\\inity", "\\infty")

    # and 
    string = string.replace("and", "")
    string = string.replace("\\mathbf", "")

    # use regex to remove \mbox{...}
    string = re.sub(r"\\mbox{.*?}", "", string)

    # quote
    string.replace("'", "")
    string.replace("\"", "")
    
    # i, j
    if "j" in string and "i" not in string:
        string = string.replace("j", "i")

    # replace a.000b where b is not number or b is end, with ab, use regex
    string = re.sub(r"(\d+)\.0*([^\d])", r"\1\2", string)
    string = re.sub(r"(\d+)\.0*$", r"\1", string)

    # if empty, return empty string
    if len(string) == 0:
        return string
    if string[0] == ".":
        string = "0" + string

    # to consider: get rid of e.g. "k = " or "q = " at beginning
    if len(string.split("=")) == 2:
        if len(string.split("=")[0]) <= 2:
            string = string.split("=")[1]

    string = _fix_sqrt(string)
    string = string.replace(" ", "")

    # \frac1b or \frac12 --> \frac{1}{b} and \frac{1}{2}, etc. Even works with \frac1{72} (but not \frac{72}1). Also does a/b --> \\frac{a}{b}
    string = _fix_fracs(string)

    # NOTE: X/Y changed to \frac{X}{Y} in dataset, but in simple cases fix in case the model output is X/Y
    string = _fix_a_slash_b(string)

    return string


def extract_multi_choice_answer(pred_str):
    # TODO: SFT models
    if 'Problem:' in pred_str:
        pred_str = pred_str.split("Problem:", 1)[0]
    pred_str = pred_str.replace("choice is", "answer is")
    patt = regex.search(r"answer is \(?(?P<ans>[abcde])\)?", pred_str.lower())
    if patt is not None:
        return patt.group('ans').upper()
    return 'placeholder'


def extract_answer(pred_str, data_name):
    if data_name in ["mmlu_stem", "sat_math", "mathqa"]:
        return extract_multi_choice_answer(pred_str)

    if 'final answer is $' in pred_str and '$. I hope' in pred_str:
        # minerva_math
        tmp = pred_str.split('final answer is $', 1)[1]
        pred = tmp.split('$. I hope', 1)[0].strip()
    elif 'boxed' in pred_str:
        ans = pred_str.split('boxed')[-1]
        if len(ans) == 0:
            return ""
        elif ans[0] == '{':
            stack = 1
            a = ''
            for c in ans[1:]:
                if (c == '{'):
                    stack += 1
                    a += c
                elif (c == '}'):
                    stack -= 1
                    if (stack == 0): break
                    a += c
                else:
                    a += c
        else:
            a = ans.split('$')[0].strip()
        pred = a
    elif ('he answer is' in pred_str):
        pred = pred_str.split('he answer is')[-1].strip()
    elif ('final answer is' in pred_str):
        pred = pred_str.split('final answer is')[-1].strip()
    # elif extract_program_output(pred_str) != "":
        # fall back to program
        # pred = extract_program_output(pred_str)
    else: # use the last number
        pattern = '-?\d*\.?\d+'
        pred = re.findall(pattern, pred_str.replace(",", ""))
        if(len(pred) >= 1):
            pred = pred[-1]
        else: pred = ''

    # multiple line
    # pred = pred.split("\n")[0]
    pred = re.sub(r"\n\s*", "", pred)
    if pred != "" and pred[0] == ":":
        pred = pred[1:]
    if pred != "" and pred[-1] == ".":
        pred = pred[:-1]
    if pred != "" and pred[-1] == "/":
        pred = pred[:-1]
    pred = strip_string(pred)
    return pred


def parse_ground_truth(example: Dict[str, Any], data_name):
    # parse ground truth
    if data_name in ["MATH", "math", "math_oai", "minerva_math", "ocw", "amps", "hungarian_exam"]:
        gt_ans = example['answer']
    elif data_name == "gsm8k":
        gt_ans = example['answer'].split("####")[-1]
    elif data_name == "mmlu_stem":
        abcd = 'ABCD'
        gt_ans = abcd[example['answer']]
    elif data_name == "gpqa":
        gt_ans = example['correct answer']
    else:
        raise NotImplementedError(f"`{data_name}`")
    # post process
    gt_ans = strip_string(gt_ans)
    return gt_ans


def parse_question(example, data_name):
    question = ""
    if data_name == "mmlu_stem":
        options = example['choices']
        assert len(options) == 4
        for i, (label, option) in enumerate(zip('ABCD', options)):
            options[i] = f"({label}) {str(option).strip()}"
        options = ", ".join(options)
        question = f"{example['question'].strip()}\nWhat of the following is the right choice? Explain your answer.\n{options}"
    else:
        for key in ['question', 'problem', 'Question', 'input']:
            if key in example:
                question = example[key]
                break
    assert question != ""
    # Yes or No question
    gt_ans = parse_ground_truth(example, data_name)
    gt_lower = gt_ans.lower()
    if gt_lower in ["true", "false"]:
        question += " (True or False)"
    if gt_lower in ["yes", "no"]:
        question += " (Yes or No)"
    return question.strip()


def _test_extract_answer():
    text= """
    The answer is $\\boxed{\left(                                                                                                                      
\\begin{array}{ccc}                                                                                                                                          
 -13 & 4 & -2 \\\\
 7 & 8 & -3 \\\\
 0 & 18 & -7 \\\\
 6 & 12 & 5 \\\\
\\end{array}
\\right)}$.
"""
    print(extract_answer(text, "math"))
    # should output a dict


if __name__ == "__main__":
    _test_extract_answer()