import Joi from "joi";
import moment from "moment";
import validator from "validator";

const appointmentTimeSchema = Joi.object().keys({
    date: Joi.date().required(),
    available: Joi.boolean().required()
});

const customInputSchema = Joi.object().keys({
    name: Joi.string().required(),
    type: Joi.string().required()
}).unknown(true);

function isValidEmail(email) {
    const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
    return emailRegex.test(email);
}

function isDueDatePassed(dueDate) {
    return moment(dueDate, 'YYYY-MM-DD', true).isBefore();
}

function isDatePassed(dateA, dateB) {
    const dueDateA = new Date(dateA);
    const dueDateB = new Date(dateB);
    return dueDateA < dueDateB;
}


function isInputValid(data, inputs) {
    if (!isValidCustomInput(inputs)) {
        return false;
    }

    // check for duplicates
    const seenNames = new Set();
    for (const element of data) {
        if (seenNames.has(element.name)) {
            return false; // Duplicate found
        }
        seenNames.add(element.name);
    }

    // validate each input dynamically based on its type
    return data.every(element => {
        const inputDefinition = inputs.find(input => input.name === element.name);
        if (!inputDefinition) {
            return false; // If the input is not in the expected schema, fail validation
        }

        switch (inputDefinition.type) {
            case "email":
                return validator.isEmail(element.value);

            case "text":
                return !validator.isEmpty(element.value.trim()); // Trim to prevent spaces from being valid

            case "tel":
                return validator.isMobilePhone(element.value, "any", { strictMode: false });

            default:
                return false; // Reject unknown input types
        }
    });
}

function isValidCustomInput(data) {
    return !data.some(element => {
        const { error } = customInputSchema.validate(element);
        if (error) {
            console.log("Validation failed:", error.details);
            return true; // `some()` stops when this is true
        }
        return false;
    });
}

function isValidAppointmentTimes(data) {
    return data.every(item => {
        // Validate date format strictly using Moment.js
        const isDateValid = moment(item.date, 'YYYY-MM-DDTHH:mm', true).isValid();

        // Validate item against the schema
        const { error } = appointmentTimeSchema.validate(item);

        return isDateValid && !error;
    });
}

function validateDates(res, startDate, endDate, dueDate) {
    if (isDatePassed(startDate, dueDate)) {
        res.status(400).json({ 'message': 'Due date is after start date' });
        return false;
    }

    if (isDueDatePassed(dueDate)) {
        res.status(400).json({ 'message': 'Due date is in the past' });
        return false;
    }

    if (isDatePassed(endDate, startDate)) {
        res.status(400).json({ 'message': 'End date is before start date' });
        return false;
    }

    return true;
}

export {isValidEmail, isDueDatePassed, isDatePassed, validateDates, isValidAppointmentTimes, appointmentTimeSchema, isValidCustomInput, isInputValid};