import Button from "@/components/Low/Button";
import axios from "axios";
import { useEffect, useState } from "react";
import { toast } from "react-toastify";
import { useFilePicker } from "use-file-picker";
import readXlsxFile from "read-excel-file";
import Modal from "@/components/Modal";
import { PermissionType } from "@/interfaces/permissions";
import moment from "moment";
import { checkAccess, getTypesOfUser } from "@/utils/permissions";
import Checkbox from "@/components/Low/Checkbox";
import ReactDatePicker from "react-datepicker";
import clsx from "clsx";
import countryCodes from "country-codes-list";
import { User, Type as UserType } from "@/interfaces/user";
import { Type, UserImport } from "../../../interfaces/IUserImport";
import UserTable from "../../../components/Tables/UserTable";
import { EntityWithRoles } from "@/interfaces/entity";
import Select from "@/components/Low/Select";
import { IoInformationCircleOutline } from "react-icons/io5";
import { FaFileDownload } from "react-icons/fa";
import { HiOutlineDocumentText } from "react-icons/hi";
import UserImportSummary, { ExcelUserDuplicatesMap } from "@/components/ImportSummaries/User";
import { v4 } from "uuid";

const EMAIL_REGEX = new RegExp(/^[a-zA-Z0-9]+(?:\.[a-zA-Z0-9]+)*@[a-zA-Z0-9]+(?:\.[a-zA-Z0-9]+)*$/);

const USER_TYPE_LABELS: { [key in Type]: string } = {
	student: "Student",
	teacher: "Teacher",
	corporate: "Corporate",
};

const USER_TYPE_PERMISSIONS: {
	[key in UserType]: { perm: PermissionType | undefined; list: UserType[] };
} = {
	student: {
		perm: "createCodeStudent",
		list: [],
	},
	teacher: {
		perm: "createCodeTeacher",
		list: [],
	},
	agent: {
		perm: "createCodeCountryManager",
		list: ["student", "teacher", "corporate", "mastercorporate"],
	},
	corporate: {
		perm: "createCodeCorporate",
		list: ["student", "teacher"],
	},
	mastercorporate: {
		perm: undefined,
		list: ["student", "teacher", "corporate"],
	},
	admin: {
		perm: "createCodeAdmin",
		list: ["student", "teacher", "agent", "corporate", "mastercorporate"],
	},
	developer: {
		perm: undefined,
		list: ["student", "teacher", "agent", "corporate", "admin", "developer", "mastercorporate"],
	},
};

interface Props {
	user: User;
	permissions: PermissionType[];
	entities?: EntityWithRoles[]
	onFinish: () => void;
}


export default function BatchCreateUser({ user, entities = [], permissions, onFinish }: Props) {
	const [infos, setInfos] = useState<UserImport[]>([]);
	const [parsedExcel, setParsedExcel] = useState<{ rows?: any[]; errors?: any[] }>({ rows: undefined, errors: undefined });

	const [duplicatedUsers, setDuplicatedUsers] = useState<UserImport[]>([]);
	const [newUsers, setNewUsers] = useState<UserImport[]>([]);
	const [duplicatedRows, setDuplicatedRows] = useState<{ duplicates: ExcelUserDuplicatesMap, count: number }>();

	const [isLoading, setIsLoading] = useState(false);
	const [expiryDate, setExpiryDate] = useState<Date | null>(
		user?.subscriptionExpirationDate ? moment(user.subscriptionExpirationDate).toDate() : null,
	);
	const [isExpiryDateEnabled, setIsExpiryDateEnabled] = useState(true);
	const [type, setType] = useState<Type>("student");
	const [showHelp, setShowHelp] = useState(false);
	const [entity, setEntity] = useState<{ id: string | null, label: string | null } | undefined>(() => {
		if (!entities?.length) {
			return undefined;
		}
		return {
			id: entities[0].id,
			label: entities[0].label
		};
	});

	const { openFilePicker, filesContent, clear } = useFilePicker({
		accept: ".xlsx",
		multiple: false,
		readAs: "ArrayBuffer",
	});

	useEffect(() => {
		if (!isExpiryDateEnabled) setExpiryDate(null);
	}, [isExpiryDateEnabled]);

	const schema = {
		'First Name': {
			prop: 'firstName',
			type: String,
			required: true,
			validate: (value: string) => {
				if (!value || value.trim() === '') {
					throw new Error('First Name cannot be empty')
				}
				return true
			}
		},
		'Last Name': {
			prop: 'lastName',
			type: String,
			required: true,
			validate: (value: string) => {
				if (!value || value.trim() === '') {
					throw new Error('Last Name cannot be empty')
				}
				return true
			}
		},
		'Student ID': {
			prop: 'studentID',
			type: String,
			required: true,
			validate: (value: string) => {
				if (!value || value.trim() === '') {
					throw new Error('Student ID cannot be empty')
				}
				return true
			}
		},
		'Passport/National ID': {
			prop: 'passport_id',
			type: String,
			required: true,
			validate: (value: string) => {
				if (!value || value.trim() === '') {
					throw new Error('Passport/National ID cannot be empty')
				}
				return true
			}
		},
		'E-mail': {
			prop: 'email',
			required: true,
			type: (value: any) => {
				if (!value || value.trim() === '') {
					throw new Error('Email cannot be empty')
				}
				if (!EMAIL_REGEX.test(value.trim())) {
					throw new Error('Invalid Email')
				}
				return value
			}
		},
		'Phone Number': {
			prop: 'phone',
			type: Number,
			required: true,
			validate: (value: number) => {
				if (value === null || value === undefined || String(value).trim() === '') {
					throw new Error('Phone Number cannot be empty')
				}
				return true
			}
		},
		'Classroom Name': {
			prop: 'group',
			type: String,
			required: true,
			validate: (value: string) => {
				if (!value || value.trim() === '') {
					throw new Error('Classroom Name cannot be empty')
				}
				return true
			}
		},
		'Country': {
			prop: 'country',
			type: (value: any) => {
				if (!value || value.trim() === '') {
					throw new Error('Country cannot be empty')
				}
				const validCountry = countryCodes.findOne("countryCode" as any, value.toUpperCase()) ||
					countryCodes.all().find((x) => x.countryNameEn.toLowerCase() === value.toLowerCase());
				if (!validCountry) {
					throw new Error('Invalid Country/Country Code')
				}
				return validCountry;
			},
			required: true
		}
	}

	useEffect(() => {
		if (filesContent.length > 0) {
			const file = filesContent[0];
			readXlsxFile(
				file.content, { schema, ignoreEmptyRows: false })
				.then((data) => {
					setParsedExcel(data)
				});
		}
		// eslint-disable-next-line react-hooks/exhaustive-deps
	}, [filesContent]);

	useEffect(() => {
		if (parsedExcel.rows) {
			const duplicates: ExcelUserDuplicatesMap = {
				studentID: new Map(),
				email: new Map(),
				passport_id: new Map(),
				phone: new Map()
			};
			const duplicateValues = new Set<string>();
			const duplicateRowIndices = new Set<number>();

			const errorRowIndices = new Set(
				parsedExcel.errors?.map(error => error.row) || []
			);

			parsedExcel.rows.forEach((row, index) => {
				if (!errorRowIndices.has(index + 2)) {
					(Object.keys(duplicates) as Array<keyof ExcelUserDuplicatesMap>).forEach(field => {
						if (row !== null) {
							const value = row[field];
							if (value) {
								if (!duplicates[field].has(value)) {
									duplicates[field].set(value, [index + 2]);
								} else {
									const existingRows = duplicates[field].get(value);
									if (existingRows) {
										existingRows.push(index + 2);
										duplicateValues.add(value);
										existingRows.forEach(rowNum => duplicateRowIndices.add(rowNum));
									}
								}
							}
						}
					});
				}
			});

			const infos = parsedExcel.rows
				.map((row, index) => {
					if (errorRowIndices.has(index + 2) || duplicateRowIndices.has(index + 2) || row === null) {
						return undefined;
					}
					const { firstName, lastName, studentID, passport_id, email, phone, group, country } = row;
					if (!email || !EMAIL_REGEX.test(email.toString().trim())) {
						return undefined;
					}

					return {
						email: email.toString().trim().toLowerCase(),
						name: `${firstName ?? ""} ${lastName ?? ""}`.trim(),
						type: type,
						passport_id: passport_id?.toString().trim() || undefined,
						groupName: group,
						studentID,
						entity,
						demographicInformation: {
							country: country?.countryCode,
							passport_id: passport_id?.toString().trim() || undefined,
							phone: phone.toString(),
						},
					} as UserImport;
				})
				.filter((item): item is UserImport => item !== undefined);

			setDuplicatedRows({ duplicates, count: duplicateRowIndices.size });
			setInfos(infos);
			setNewUsers([]);
			setDuplicatedUsers([]);
		}
	}, [entity, parsedExcel, type]);


	useEffect(() => {
		const crossReferenceEmails = async () => {
			try {
				const response = await axios.post("/api/users/controller?op=crossRefEmails", {
					emails: infos.map((x) => x.email)
				});

				const crossRefEmails = response.data;
				if (!!crossRefEmails) {
					const existingEmails = new Set(crossRefEmails.map((x: any) => x.email));
					const dupes = infos.filter(info => existingEmails.has(info.email));
					const newUsersList = infos
						.filter(info => !existingEmails.has(info.email))
						.map(info => ({
							...info,
							entityLabels: [entity!.label!]
						}));
					setNewUsers(newUsersList);

					const { data: emailEntityMap } = await axios.post("/api/users/controller?op=getEntities", {
						emails: dupes.map((x) => x.email)
					});
					const withLabels = dupes.map((u) => ({
						...u,
						entityLabels: emailEntityMap.find((e: any) => e.email === u.email)?.entityLabels || []
					}))
					setDuplicatedUsers(withLabels);
				} else {
					const withLabel = infos.map(info => ({
						...info,
						entityLabels: [entity!.label!]
					}));
					setNewUsers(withLabel);
				}
			} catch (error) {
				toast.error("Something went wrong, please try again later!");
			}
		};

		if (infos.length > 0) {
			crossReferenceEmails();
		}
	}, [infos, entity]);

	const makeUsers = async () => {
		const newUsersSentence = newUsers.length > 0 ? `create ${newUsers.length} user(s)` : undefined;
		const existingUsersSentence = duplicatedUsers.length > 0 ? `invite ${duplicatedUsers.length} registered student(s)` : undefined;

		if (!confirm(`You are about to ${[newUsersSentence, existingUsersSentence].filter((x) => !!x).join(" and ")}, are you sure you want to continue?`))
			return;

		if (newUsers.length > 0) {
			setIsLoading(true);
			try {
				const withIds = newUsers.map((user) => ({ ...user, type, expiryDate, id: v4() }));
				await axios.post("/api/batch_users", { users: withIds});
				toast.success(`Successfully added ${withIds.length} user(s)!`);
				Promise.all(withIds.map(async (u) => await axios.post(`/api/invites`, { to: u.id, entity: entity?.id, from: user.id })))
					.then(() => toast.success(`Successfully invited ${withIds.length} registered student(s)!`))
					.finally(() => {
						if (withIds.length === 0) setIsLoading(false);
					});
				onFinish();
			} catch (e) {
				console.error(e)
				toast.error("Something went wrong, please try again later!");
			} finally {
				setIsLoading(false);
				setInfos([]);
				clear();
			}
		} else {
			setIsLoading(false);
			setInfos([]);
			clear();
		}
	};


	const handleTemplateDownload = () => {
		const fileName = "UsersTemplate.xlsx";
		const url = `https://firebasestorage.googleapis.com/v0/b/encoach-staging.appspot.com/o/import_templates%2F${fileName}?alt=media&token=b771a535-bf95-4060-889c-a086df65d480`;

		const link = document.createElement('a');
		link.href = url;

		link.download = fileName;

		document.body.appendChild(link);
		link.click();
		document.body.removeChild(link);
	};

	return (
		<>
			<Modal isOpen={showHelp} onClose={() => setShowHelp(false)}>
				<>
					<div className="flex font-bold text-xl justify-center text-gray-700"><span>Excel File Format</span></div>
					<div className="mt-4 flex flex-col gap-4">
						<div className="flex flex-col gap-3 bg-gray-100 rounded-lg p-4">
							<div className="flex items-center gap-2">
								<HiOutlineDocumentText className={`w-5 h-5 text-mti-purple-light`} />
								<h2 className="text-lg font-semibold">
									The uploaded document must:
								</h2>
							</div>
							<ul className="flex flex-col pl-10 gap-2">
								<li className="text-gray-700 list-disc">
									be an Excel .xlsx document.
								</li>
								<li className="text-gray-700 list-disc">
									only have a single spreadsheet with the following <b>exact same name</b> columns:
									<div className="py-4 pr-4">
										<table className="w-full bg-white">
											<thead>
												<tr>
													<th className="border border-neutral-200 px-2 py-1">First Name</th>
													<th className="border border-neutral-200 px-2 py-1">Last Name</th>
													<th className="border border-neutral-200 px-2 py-1">Student ID</th>
													<th className="border border-neutral-200 px-2 py-1">Passport/National ID</th>
													<th className="border border-neutral-200 px-2 py-1">E-mail</th>
													<th className="border border-neutral-200 px-2 py-1">Phone Number</th>
													<th className="border border-neutral-200 px-2 py-1">Classroom Name</th>
													<th className="border border-neutral-200 px-2 py-1">Country</th>
												</tr>
											</thead>
										</table>
									</div>
								</li>
							</ul>
						</div>
						<div className="flex flex-col gap-3 bg-gray-100 rounded-lg p-4">
							<div className="flex items-center gap-2">
								<IoInformationCircleOutline className={`w-5 h-5 text-mti-purple-light`} />
								<h2 className="text-lg font-semibold">
									Note that:
								</h2>
							</div>
							<ul className="flex flex-col pl-10 gap-2">
								<li className="text-gray-700 list-disc">
									all incorrect e-mails will be ignored.
								</li>
								<li className="text-gray-700 list-disc">
									all already registered e-mails will be ignored.
								</li>
								<li className="text-gray-700 list-disc">
									all rows which contain duplicate values in the columns: &quot;Student ID&quot;, &quot;Passport/National ID&quot;, &quot;E-mail&quot;, will be ignored.
								</li>
								<li className="text-gray-700 list-disc">
									all of the e-mails in the file will receive an e-mail to join EnCoach with the role selected below.
								</li>
							</ul>
						</div>
						<div className="bg-gray-100 rounded-lg p-4">
							<p className="text-gray-600">
								{`The downloadable template is an example of a file that can be imported. Your document doesn't need to be a carbon copy of the template - it can have different styling but it must adhere to the previous requirements.`}
							</p>
						</div>
						<div className="w-full flex justify-between mt-6 gap-8">
							<Button color="purple" onClick={() => setShowHelp(false)} variant="outline" className="self-end w-full bg-white">
								Close
							</Button>

							<Button color="purple" onClick={handleTemplateDownload} variant="solid" className="self-end w-full">
								<div className="flex items-center gap-2">
									<FaFileDownload size={24} />
									Download Template
								</div>
							</Button>
						</div>
					</div>
				</>
			</Modal>
			<div className="border-mti-gray-platinum flex flex-col gap-4 rounded-xl border p-4">
				<div className="grid grid-cols-2 -md:grid-cols-1 gap-4">
					<div className="flex flex-col gap-4">
						<div className="flex items-end justify-between">
							<label className="text-mti-gray-dim text-base font-normal">Choose an Excel file</label>
							<button
								onClick={() => setShowHelp(true)}
								className="tooltip cursor-pointer p-1.5 hover:bg-gray-200 rounded-full transition-colors duration-200"
								data-tip="Excel File Format"
							>
								<IoInformationCircleOutline size={24} />
							</button>
						</div>
						<Button onClick={openFilePicker} isLoading={isLoading} disabled={isLoading}>
							{filesContent.length > 0 ? filesContent[0].name : "Choose a file"}
						</Button>
					</div>
					<div className={clsx("flex flex-col gap-4")}>
						<label className="font-normal text-base text-mti-gray-dim">Entity</label>
						<Select
							defaultValue={{ value: (entities || [])[0]?.id, label: (entities || [])[0]?.label }}
							options={entities.map((e) => ({ value: e.id, label: e.label }))}
							onChange={(e) => {
								if (!e) {
									setEntity(undefined);
									return;
								}
								setEntity({
									id: e?.value,
									label: e?.label
								});
							}}
							isClearable={checkAccess(user, ["admin", "developer"])}
						/>
					</div>
				</div>
				{user && checkAccess(user, ["developer", "admin", "corporate", "mastercorporate"]) && (
					<>
						<div className="-md:flex-row -md:items-center flex justify-between gap-2 md:flex-col 2xl:flex-row 2xl:items-center">
							<label className="text-mti-gray-dim text-base font-normal">Expiry Date</label>
							<Checkbox isChecked={isExpiryDateEnabled} onChange={setIsExpiryDateEnabled} disabled={!!user.subscriptionExpirationDate}>
								Enabled
							</Checkbox>
						</div>
						{isExpiryDateEnabled && (
							<ReactDatePicker
								className={clsx(
									"flex min-h-[70px] w-full cursor-pointer justify-center rounded-full border p-6 text-sm font-normal focus:outline-none",
									"hover:border-mti-purple tooltip",
									"transition duration-300 ease-in-out",
								)}
								filterDate={(date) =>
									moment(date).isAfter(new Date()) &&
									(user.subscriptionExpirationDate ? moment(date).isBefore(user.subscriptionExpirationDate) : true)
								}
								dateFormat="dd/MM/yyyy"
								selected={expiryDate}
								onChange={(date) => setExpiryDate(date)}
							/>
						)}
					</>
				)}
				<label className="text-mti-gray-dim text-base font-normal">Select the type of user they should be</label>
				{user && (
					<select
						defaultValue="student"
						onChange={(e) => setType(e.target.value as Type)}
						className="flex min-h-[70px] w-full min-w-[350px] cursor-pointer justify-center rounded-full border bg-white p-6 text-sm font-normal focus:outline-none">
						{Object.keys(USER_TYPE_LABELS)
							.filter((x) => {
								const { list, perm } = USER_TYPE_PERMISSIONS[x as Type];
								// if (x === "corporate") console.log(list, perm, checkAccess(user, list, permissions, perm));
								return checkAccess(user, getTypesOfUser(list), permissions, perm);
							})
							.map((type) => (
								<option key={type} value={type}>
									{USER_TYPE_LABELS[type as keyof typeof USER_TYPE_LABELS]}
								</option>
							))}
					</select>
				)}
				{parsedExcel.rows !== undefined && <UserImportSummary parsedExcel={parsedExcel} newUsers={newUsers} enlistedUsers={duplicatedUsers} duplicateRows={duplicatedRows} />}
				{newUsers.length !== 0 && (
					<div className="flex w-full flex-col gap-4">
						<span className="text-mti-gray-dim text-base font-normal">New Users:</span>
						<UserTable users={newUsers} />
					</div>
				)}
				{(duplicatedUsers.length !== 0 && newUsers.length === 0) && <span className="text-red-500 font-bold">The imported .csv only contains duplicated users!</span>}
				<Button className="my-auto mt-4" onClick={makeUsers} disabled={newUsers.length === 0}>
					Create {newUsers.length !== 0 ? `${newUsers.length} new user${newUsers.length > 1 ? 's' : ''}` : ''}
				</Button>
			</div>
		</>
	);
}