import Button from "@/components/Low/Button";
import Checkbox from "@/components/Low/Checkbox";
import { PERMISSIONS } from "@/constants/userPermissions";
import useUsers from "@/hooks/useUsers";
import { Type, User } from "@/interfaces/user";
import { USER_TYPE_LABELS } from "@/resources/user";
import axios from "axios";
import clsx from "clsx";
import { capitalize, uniqBy } from "lodash";
import moment from "moment";
import { useEffect, useState } from "react";
import ReactDatePicker from "react-datepicker";
import { toast } from "react-toastify";
import ShortUniqueId from "short-unique-id";
import { useFilePicker } from "use-file-picker";
import readXlsxFile from "read-excel-file";
import Modal from "@/components/Modal";
import { BsFileEarmarkEaselFill, BsQuestionCircleFill } from "react-icons/bs";
import { checkAccess, getTypesOfUser } from "@/utils/permissions";
import { PermissionType } from "@/interfaces/permissions";
import usePermissions from "@/hooks/usePermissions";
import { EntityWithRoles } from "@/interfaces/entity";
import Select from "@/components/Low/Select";
import CodeGenImportSummary, { ExcelCodegenDuplicatesMap } from "@/components/ImportSummaries/Codegen";
import { FaFileDownload } from "react-icons/fa";
import { IoInformationCircleOutline } from "react-icons/io5";
import { HiOutlineDocumentText } from "react-icons/hi";
import CodegenTable from "@/components/Tables/CodeGenTable";

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

const USER_TYPE_PERMISSIONS: {
	[key in Type]: { perm: PermissionType | undefined; list: Type[] };
} = {
	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", "admin", "mastercorporate"],
	},
	developer: {
		perm: undefined,
		list: ["student", "teacher", "agent", "corporate", "admin", "developer", "mastercorporate"],
	},
};

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

export default function BatchCodeGenerator({ user, users, entities = [], permissions, onFinish }: Props) {
	const [infos, setInfos] = useState<{ email: string; name: string; passport_id: string }[]>([]);
	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((entities || [])[0]?.id || undefined);
	const [parsedExcel, setParsedExcel] = useState<{ rows?: any[]; errors?: any[] }>({ rows: undefined, errors: undefined });
	const [duplicatedRows, setDuplicatedRows] = useState<{ duplicates: ExcelCodegenDuplicatesMap, count: number }>();

	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
			}
		},
		'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
			}
		}
	}

	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: ExcelCodegenDuplicatesMap = {
				email: new Map(),
				passport_id: 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 ExcelCodegenDuplicatesMap>).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 info = 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(),
						passport_id: passport_id?.toString().trim() || undefined,
					};
				}).filter((x) => !!x) as typeof infos;

			setInfos(info);
		}
	}, [entity, parsedExcel, type]);

	const generateAndInvite = async () => {
		const newUsers = infos.filter((x) => !users.map((u) => u.email).includes(x.email));
		const existingUsers = infos
			.filter((x) => users.map((u) => u.email).includes(x.email))
			.map((i) => users.find((u) => u.email === i.email))
			.filter((x) => !!x && x.type === "student") as User[];

		const newUsersSentence = newUsers.length > 0 ? `generate ${newUsers.length} code(s)` : undefined;
		const existingUsersSentence = existingUsers.length > 0 ? `invite ${existingUsers.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;

		setIsLoading(true);
		Promise.all(existingUsers.map(async (u) => await axios.post(`/api/invites`, { to: u.id, from: user.id })))
			.then(() => toast.success(`Successfully invited ${existingUsers.length} registered student(s)!`))
			.finally(() => {
				if (newUsers.length === 0) setIsLoading(false);
			});

		if (newUsers.length > 0) generateCode(type, newUsers);
		setInfos([]);
	};

	const generateCode = (type: Type, informations: typeof infos) => {
		const uid = new ShortUniqueId();
		const codes = informations.map(() => uid.randomUUID(6));

		setIsLoading(true);
		axios
			.post<{ ok: boolean; valid?: number; reason?: string }>("/api/code", {
				type,
				codes,
				infos: informations.map((info, index) => ({ ...info, code: codes[index] })),
				expiryDate,
				entity
			})
			.then(({ data, status }) => {
				if (data.ok) {
					toast.success(
						`Successfully generated${data.valid ? ` ${data.valid}/${informations.length}` : ""} ${capitalize(
							type,
						)} codes and they have been notified by e-mail!`,
						{ toastId: "success" },
					);

					onFinish();
					return;
				}

				if (status === 403) {
					toast.error(data.reason, { toastId: "forbidden" });
				}
			})
			.catch(({ response: { status, data } }) => {
				if (status === 403) {
					toast.error(data.reason, { toastId: "forbidden" });
					return;
				}

				toast.error(`Something went wrong, please try again later!`, {
					toastId: "error",
				});
			})
			.finally(() => {
				setIsLoading(false);
				return clear();
			});
	};

	const handleTemplateDownload = () => {
		const fileName = "BatchCodeTemplate.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">Passport/National ID</th>
													<th className="border border-neutral-200 px-2 py-1">E-mail</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;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="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>
				{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)}
							/>
						)}
					</>
				)}
				<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) => setEntity(e?.value || undefined)}
						isClearable={checkAccess(user, ["admin", "developer"])}
					/>
				</div>
				<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 typeof user.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];
								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>
				)}
				{infos.length > 0 && <CodeGenImportSummary infos={infos} parsedExcel={parsedExcel} duplicateRows={duplicatedRows}/>}
				{infos.length !== 0 && (
					<div className="flex w-full flex-col gap-4">
						<span className="text-mti-gray-dim text-base font-normal">Codes will be sent to:</span>
						<CodegenTable infos={infos} />
					</div>
				)}
				{checkAccess(user, ["developer", "admin", "corporate", "mastercorporate"], permissions, "createCodes") && (
					<Button onClick={generateAndInvite} disabled={infos.length === 0 || (isExpiryDateEnabled ? !expiryDate : false)}>
						Generate & Send
					</Button>
				)}
			</div>
		</>
	);
}