Move stepper into its own component

Author: samejr

apps/webapp/app/components/primitives/InputNumberStepper.tsx

@@ -0,0 +1,218 @@
+import { MinusIcon, PlusIcon } from "@heroicons/react/20/solid";
+import { type ChangeEvent, useRef } from "react";
+import { cn } from "~/utils/cn";
+
+type InputNumberStepperProps = JSX.IntrinsicElements["input"] & {
+  step?: number;
+  min?: number;
+  max?: number;
+  round?: boolean;
+  controlSize?: "base" | "large";
+};
+
+export function InputNumberStepper({
+  value,
+  onChange,
+  step = 50,
+  min,
+  max,
+  round = true,
+  controlSize = "base",
+  name,
+  id,
+  disabled = false,
+  readOnly = false,
+  className,
+  placeholder = "Type a number",
+}: InputNumberStepperProps) {
+  const inputRef = useRef<HTMLInputElement>(null);
+
+  const handleStepUp = () => {
+    if (!inputRef.current || disabled) return;
+
+    // If rounding is enabled, ensure we start from a rounded base before stepping
+    if (round) {
+      // If field is empty, treat as 0 (or min if provided) before stepping up
+      if (inputRef.current.value === "") {
+        inputRef.current.value = String(min ?? 0);
+      } else {
+        commitRoundedFromInput();
+      }
+    }
+    inputRef.current.stepUp();
+    const event = new Event("change", { bubbles: true });
+    inputRef.current.dispatchEvent(event);
+  };
+
+  const handleStepDown = () => {
+    if (!inputRef.current || disabled) return;
+
+    // If rounding is enabled, ensure we start from a rounded base before stepping
+    if (round) {
+      // If field is empty, treat as 0 (or min if provided) before stepping down
+      if (inputRef.current.value === "") {
+        inputRef.current.value = String(min ?? 0);
+      } else {
+        commitRoundedFromInput();
+      }
+    }
+    inputRef.current.stepDown();
+    const event = new Event("change", { bubbles: true });
+    inputRef.current.dispatchEvent(event);
+  };
+
+  const numericValue = value === "" ? NaN : (value as number);
+  const isMinDisabled = min !== undefined && !Number.isNaN(numericValue) && numericValue <= min;
+  const isMaxDisabled = max !== undefined && !Number.isNaN(numericValue) && numericValue >= max;
+
+  function clamp(val: number): number {
+    if (Number.isNaN(val)) return typeof value === "number" ? value : min ?? 0;
+    let next = val;
+    if (min !== undefined) next = Math.max(min, next);
+    if (max !== undefined) next = Math.min(max, next);
+    return next;
+  }
+
+  function roundToStep(val: number): number {
+    if (step <= 0) return val;
+    const base = min ?? 0;
+    const shifted = val - base;
+    const quotient = shifted / step;
+    const floored = Math.floor(quotient);
+    const ceiled = Math.ceil(quotient);
+    const down = base + floored * step;
+    const up = base + ceiled * step;
+    const distDown = Math.abs(val - down);
+    const distUp = Math.abs(up - val);
+    return distUp < distDown ? up : down;
+  }
+
+  function commitRoundedFromInput() {
+    if (!inputRef.current || disabled || readOnly) return;
+    const el = inputRef.current;
+    const raw = el.value;
+    if (raw === "") return; // do not coerce empty to 0; keep placeholder visible
+    const numeric = Number(raw);
+    if (Number.isNaN(numeric)) return; // ignore non-numeric
+    const rounded = clamp(roundToStep(numeric));
+    if (String(rounded) === String(value)) return;
+    // Update the real input's value for immediate UI feedback
+    el.value = String(rounded);
+    // Invoke consumer onChange with the real element as target/currentTarget
+    onChange?.({
+      target: el,
+      currentTarget: el,
+    } as unknown as ChangeEvent<HTMLInputElement>);
+  }
+
+  const sizeStyles = {
+    base: {
+      container: "h-9",
+      input: "text-sm px-3",
+      button: "size-6",
+      icon: "size-3.5",
+      gap: "gap-1 pr-1.5",
+    },
+    large: {
+      container: "h-11 rounded-md",
+      input: "text-base px-3.5",
+      button: "size-8",
+      icon: "size-5",
+      gap: "gap-[0.3125rem] pr-[0.3125rem]",
+    },
+  } as const;
+
+  const size = sizeStyles[controlSize];
+
+  return (
+    <div
+      className={cn(
+        "flex items-center rounded border border-charcoal-600 bg-tertiary transition hover:border-charcoal-550/80 hover:bg-charcoal-600/80",
+        size.container,
+        "has-[:focus-visible]:outline has-[:focus-visible]:outline-1 has-[:focus-visible]:outline-offset-0 has-[:focus-visible]:outline-text-link",
+        disabled && "cursor-not-allowed opacity-50",
+        className
+      )}
+    >
+      <input
+        ref={inputRef}
+        type="number"
+        id={id}
+        name={name}
+        value={value}
+        placeholder={placeholder}
+        onChange={(e) => {
+          // Allow empty string to pass through so user can clear the field
+          if (e.currentTarget.value === "") {
+            // reflect emptiness in the input and notify consumer as empty
+            if (inputRef.current) inputRef.current.value = "";
+            onChange?.({
+              target: e.currentTarget,
+              currentTarget: e.currentTarget,
+            } as ChangeEvent<HTMLInputElement>);
+            return;
+          }
+          onChange?.(e);
+        }}
+        onBlur={(e) => {
+          // If blur is caused by clicking our step buttons, we prevent pointerdown
+          // so blur shouldn't fire. This is for safety in case of keyboard focus move.
+          if (round) commitRoundedFromInput();
+        }}
+        onKeyDown={(e) => {
+          if (e.key === "Enter" && round) {
+            e.preventDefault();
+            commitRoundedFromInput();
+          }
+        }}
+        step={step}
+        min={min}
+        max={max}
+        disabled={disabled}
+        readOnly={readOnly}
+        className={cn(
+          "placeholder:text-muted-foreground h-full grow border-0 bg-transparent text-left text-text-bright outline-none ring-0 focus:border-0 focus:outline-none focus:ring-0 disabled:cursor-not-allowed",
+          size.input,
+          // Hide number input arrows
+          "[type=number]:border-0 [appearance:textfield] [&::-webkit-inner-spin-button]:appearance-none [&::-webkit-outer-spin-button]:appearance-none"
+        )}
+      />
+
+      <div className={cn("flex items-center", size.gap)}>
+        <button
+          type="button"
+          onClick={handleStepDown}
+          onPointerDown={(e) => e.preventDefault()}
+          disabled={disabled || isMinDisabled}
+          aria-label={`Decrease by ${step}`}
+          className={cn(
+            "flex items-center justify-center rounded border border-error/30 bg-error/20 transition",
+            size.button,
+            "hover:border-error/50 hover:bg-error/30",
+            "disabled:cursor-not-allowed disabled:opacity-40",
+            "focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-text-link"
+          )}
+        >
+          <MinusIcon className={cn("text-error", size.icon)} />
+        </button>
+
+        <button
+          type="button"
+          onClick={handleStepUp}
+          onPointerDown={(e) => e.preventDefault()}
+          disabled={disabled || isMaxDisabled}
+          aria-label={`Increase by ${step}`}
+          className={cn(
+            "flex items-center justify-center rounded border border-success/30 bg-success/10 transition",
+            size.button,
+            "hover:border-success/40 hover:bg-success/20",
+            "disabled:cursor-not-allowed disabled:opacity-40 disabled:hover:bg-transparent",
+            "focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-text-link"
+          )}
+        >
+          <PlusIcon className={cn("text-success", size.icon)} />
+        </button>
+      </div>
+    </div>
+  );
+}