import pandas
import numpy


# --------------------- FUNCTIONS ---------------------
def make_statement(statement, decoration):
    """Emphasises headings by adding decoration
    at the start and end"""

    return f"{decoration * 3} {statement} {decoration * 3}"


def string_check(question, valid_ans_list=('yes', 'no'),
                 num_letters=1):
    """Checks that user enters the full word
    or the first letter of a word from a list of valid responses"""

    while True:

        response = input(question).lower()

        for item in valid_ans_list:

            # Check if the response matches a valid full word
            if response == item:
                return item

            # Check if the response matches the first letter of a valid word
            elif response == item[:num_letters]:
                return item

        # ask user again if the input is invalid
        print(f"Please choose an option from {valid_ans_list}")



def instructions():
    make_statement("Instructions", "ℹ️")

    print('''
    
When you start my program it will ask ...
- Instructions
- Name
- budget
- Display a list of vegetables with corresponding numbers to purchase

The program will record the purchases and calculate the cost/budget.

Users will have the option to purchase multiple vegetables and will be able to stop if wanted

It will finally show an itemised list of all the purchases

    ''')


def not_blank(question):
    """Checks that a user response is not blank or only spaces."""

    while True:
        response = input(question)

        if response.strip() == "":
            print("Sorry, this can't be blank. Please try again.")
        else:
            return response


def int_check(question, low, high):
    """Checks users enter an integer between two values"""

    error = f"Oops - please enter an integer between {low} and {high}."

    while True:

        try:
            # Change the response to an integer and check that it's within the allowed range
            response = int(input(question))

            if low <= response <= high:
                return response
            else:
                print(error)

        except ValueError:
            # Catches invalid inputs to prevent errors
            print(error)


def currency(x):
    """Formats numbers as currency ($#.##)"""
    return "${:.2f}".format(x)


# --------------------- MAIN ROUTINE ---------------------

# Max budget
MAX_SPEND = 1000
budget = 0

# lists to hold vegetable names and costs
all_vegetables = ["Potatoes", "Carrots", "Cabbage", "Onions",
                  "Pumpkin", "Cauliflower", "Broccoli", "Lettuce",
                  "Tomatoes", "Cucumber"]
all_vegetables_costs = [2.20, 2.50, 2.70, 3.00, 3.30, 3.60,
                        4.00, 7.00, 10.00, 13.20]

vegetable_dict = {
    'Vegetables': all_vegetables,
    'Vegetables Price': all_vegetables_costs,
}

# create dataframe / table from dictionary
vegetables_frame = pandas.DataFrame(vegetable_dict)

# rearranging index
vegetables_frame.index = numpy.arange(1, len(vegetables_frame) + 1)

# currency formatting
add_dollars = ['Vegetables Price']
for var_item in add_dollars:
    vegetables_frame[var_item] = vegetables_frame[var_item].apply(currency)

# Display main heading
print(make_statement("Ezra's Vegetable Enterprise", "🥕"))

# Ask user if they want to see the instructions
print()
want_instructions = string_check("Do you want to see the instructions? ")

if want_instructions == "yes":
    instructions()

print()

# ask user for their name (cant be blank)
print()
name = not_blank("Name: ")

# ask user for budget between $10 and $300
budget = int_check(f"Hello {name}, what is your budget? ", 10, 300)

print(f"your budget is ${budget}")
print()

# set purchase vegetables to none
purchased_vegetables = []
purchased_prices = []

# create a purchased dict
purchased_dict = {
    'Vegetables': purchased_vegetables,
    'Vegetables Prices': purchased_prices,
}

# important list if vegetables
vegetable_string = vegetables_frame.to_string(index=False)

# --------------------- MAIN LOOP ---------------------

while budget <= MAX_SPEND:

    print()

    # display vegetables
    print("Here's a list of vegetables")
    print(vegetables_frame)
    print()

    # prompt user to select a row
    try:
        # ask user for choice
        choice = int_check("choose your Vegetable with the number of the corresponding row: ", 1, 10)

        selected_row = all_vegetables[choice - 1]
        vegetable_price = all_vegetables_costs[choice - 1]

        # check if budget fits the purchase
        if budget >= vegetable_price:
            budget -= vegetable_price

            # Add the chosen vegetable and price to list
            purchased_vegetables.append(selected_row)
            purchased_prices.append(vegetable_price)

            # display choice and new budget
            print(f"You selected {selected_row} costing ${vegetable_price} ")
            print(f"Your new budget is ${budget} ")
            print()

        else:
            # tell user if budget is insufficient
            print(f"sorry the {selected_row} costing ${vegetable_price} "
                  f"is above your current budget of ${budget}. Please try again.")
            continue

        # end loop if budget is too low for any more purchases
        if budget <= 2.2:
            print("❌ No budget left ❌")
            print()
            break

        # ask the user if they would like to purchase any more vegetables
        repurchase = string_check("Would you like to purchase another vegetable ")

        if repurchase == "no":
            break

    except ValueError:
        print("Please enter a valid number")

# --------------------- END OF LOOP ---------------------
# --------------------- PURCHASE SUMMARY ---------------------

# itemised purchase list
total_spent = sum(purchased_prices)

# create dataframe / table from dictionary
purchased_frame = pandas.DataFrame(purchased_dict)

# rearranging index
purchased_frame.index = numpy.arange(1, len(purchased_frame) + 1)

# currency formatting
add_dollars = ['Vegetables Prices']
for var_item in add_dollars:
    purchased_frame[var_item] = purchased_frame[var_item].apply(currency)

# displayed itemised purchases
if purchased_vegetables:
    print(make_statement(f"Here are your purchases!", "🍀"))
    print()
    print(purchased_frame)
    print(f"Your total amount spent is:  ${total_spent}")