"""
Script to generate test questions from the data
"""
import os
import json
import sys

from random import choice, sample, randint
from typing import Dict

from src.common import join_items_comma_and, data_dir
from src.datatypes import *


category_key = "#CATEGORY#"
product_name_key = "#PRODUCT_NAME#"
features_key = "#FEATURE_STRING#"
characteristic_key = "#CHARACTERISTIC#"


def get_random_template() -> str:
    templates = [
        f"I'm looking for a {characteristic_key} {category_key}. What would you recommend?",
        f"What features should I think about when buying a {category_key}?",
        f"What {category_key} would you recommend that has {features_key}?",
        f"What can you tell me about the {product_name_key} {category_key}?",
        f"How much is a the ElectroHome {product_name_key}?",
        f"What's your best rated {category_key}?",
        f"What {category_key}s does ElectroHome offer?",
        f"Is the {product_name_key} a good {category_key}?",
        f"I'm considering buying a new {category_key}. What should I think about and what models would you recommend?",
        f"Tell me about your {category_key}s."
    ]
    return choice(templates)


def get_random_values() -> Dict[str, str]:
    """
    Generates a random set of entries for a question
    """
    category: Category = choice(list(Category.all.values()))
    category_name = category.name[:-1].lower()
    if category_name == "tv":
        category_name = "TV"
    product: Product = choice(category.products)

    features: List[Feature] = sample(category.features, k=randint(1, 4))
    characteristic: str = choice([
        "big",
        "durable",
        "budget",
        "family",
        "compact",
        "sleek"
    ])
    return {
        category_key: category_name,
        product_name_key: product.name,
        features_key: join_items_comma_and([f.name for f in features]),
        characteristic_key: characteristic
    }


def merge_template_values(template: str, values: Dict[str, str]) -> str:
    """
    Returns a template with the values substituted in
    """
    for k, v in values.items():
        template = template.replace(k, v)
    return template


def generate_question() -> str:
    """
    Generate a single random question
    """
    DataLoader.load_data()
    template = get_random_template()
    values = get_random_values()
    return merge_template_values(template=template, values=values)


def save_questions_to_json(questions: List[str]) -> None:
    """
    Persist the questions into the file
    """
    data = {'questions': questions}
    questions_file = os.path.join(data_dir, 'json', 'test_questions.json')
    with open(questions_file, 'w') as f:
        json.dump(data, fp=f, indent=2)


def generate_questions(n: int = 100) -> None:
    """
    Generate n questions and overwrite the test_questions.json question bank
    """
    questions = [generate_question() for _ in range(n)]
    save_questions_to_json(questions=questions)


if __name__ == "__main__":
    """
    Run from the command line with the number of questions to generate
    """
    try:
        generate_questions(int(sys.argv[1]))
    except IndexError:
        generate_questions()