import {
	RiArrowDownSFill,
	RiArrowUpSFill,
	RiExternalLinkLine,
	RiPieChartLine,
	RiWallet3Line,
} from "@remixicon/react";
import Link from "next/link";
import MoneyValues from "@/components/money-values";
import type { ExpensesByCategoryData } from "@/lib/dashboard/categories/expenses-by-category";
import { getIconComponent } from "@/lib/utils/icons";
import { formatPeriodForUrl } from "@/lib/utils/period";
import { WidgetEmptyState } from "../widget-empty-state";

type ExpensesByCategoryWidgetProps = {
	data: ExpensesByCategoryData;
	period: string;
};

const buildInitials = (value: string) => {
	const parts = value.trim().split(/\s+/).filter(Boolean);
	if (parts.length === 0) {
		return "CT";
	}
	if (parts.length === 1) {
		const firstPart = parts[0];
		return firstPart ? firstPart.slice(0, 2).toUpperCase() : "CT";
	}
	const firstChar = parts[0]?.[0] ?? "";
	const secondChar = parts[1]?.[0] ?? "";
	return `${firstChar}${secondChar}`.toUpperCase() || "CT";
};

const formatPercentage = (value: number) => {
	return `${Math.abs(value).toFixed(0)}%`;
};

export function ExpensesByCategoryWidget({
	data,
	period,
}: ExpensesByCategoryWidgetProps) {
	const periodParam = formatPeriodForUrl(period);

	if (data.categories.length === 0) {
		return (
			<WidgetEmptyState
				icon={<RiPieChartLine className="size-6 text-muted-foreground" />}
				title="Nenhuma despesa encontrada"
				description="Quando houver despesas registradas, elas aparecerão aqui."
			/>
		);
	}

	return (
		<div className="flex flex-col px-0">
			{data.categories.map((category) => {
				const IconComponent = category.categoryIcon
					? getIconComponent(category.categoryIcon)
					: null;
				const initials = buildInitials(category.categoryName);
				const hasIncrease =
					category.percentageChange !== null && category.percentageChange > 0;
				const hasDecrease =
					category.percentageChange !== null && category.percentageChange < 0;
				const hasBudget = category.budgetAmount !== null;
				const budgetExceeded =
					hasBudget &&
					category.budgetUsedPercentage !== null &&
					category.budgetUsedPercentage > 100;

				const formatCurrency = (value: number) =>
					new Intl.NumberFormat("pt-BR", {
						style: "currency",
						currency: "BRL",
					}).format(value);

				const exceededAmount =
					budgetExceeded && category.budgetAmount
						? category.currentAmount - category.budgetAmount
						: 0;

				return (
					<div
						key={category.categoryId}
						className="flex flex-col py-2 border-b border-dashed last:border-0"
					>
						<div className="flex items-center justify-between gap-3">
							<div className="flex min-w-0 flex-1 items-center gap-2">
								<div className="flex size-10 shrink-0 items-center justify-center overflow-hidden rounded-full bg-muted">
									{IconComponent ? (
										<IconComponent className="size-4 text-foreground" />
									) : (
										<span className="text-xs font-semibold uppercase text-muted-foreground">
											{initials}
										</span>
									)}
								</div>

								<div className="min-w-0 flex-1">
									<div className="flex items-center gap-2">
										<Link
											href={`/categorias/${category.categoryId}?periodo=${periodParam}`}
											className="flex max-w-full items-center gap-1 text-sm font-medium text-foreground underline-offset-2 hover:underline"
										>
											<span className="truncate">{category.categoryName}</span>
											<RiExternalLinkLine
												className="size-3 shrink-0 text-muted-foreground"
												aria-hidden
											/>
										</Link>
									</div>
									<div className="flex items-center gap-2 text-xs text-muted-foreground">
										<span>
											{formatPercentage(category.percentageOfTotal)} da despesa
											total
										</span>
									</div>
								</div>
							</div>

							<div className="flex shrink-0 flex-col items-end gap-0.5">
								<MoneyValues
									className="text-foreground"
									amount={category.currentAmount}
								/>
								{category.percentageChange !== null && (
									<span
										className={`flex items-center gap-0.5 text-xs ${
											hasIncrease
												? "text-destructive"
												: hasDecrease
													? "text-success"
													: "text-muted-foreground"
										}`}
									>
										{hasIncrease && <RiArrowUpSFill className="size-3" />}
										{hasDecrease && <RiArrowDownSFill className="size-3" />}
										{formatPercentage(category.percentageChange)}
									</span>
								)}
							</div>
						</div>

						{hasBudget && category.budgetUsedPercentage !== null && (
							<div className="ml-11 flex items-center gap-1.5 text-xs">
								<RiWallet3Line
									className={`size-3 ${
										budgetExceeded ? "text-destructive" : "text-info"
									}`}
								/>
								<span
									className={budgetExceeded ? "text-destructive" : "text-info"}
								>
									{budgetExceeded ? (
										<>
											{formatPercentage(category.budgetUsedPercentage)} do
											limite - excedeu em {formatCurrency(exceededAmount)}
										</>
									) : (
										<>
											{formatPercentage(category.budgetUsedPercentage)} do
											limite
										</>
									)}
								</span>
							</div>
						)}
					</div>
				);
			})}
		</div>
	);
}