diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/App.css | 42 | ||||
| -rw-r--r-- | src/App.tsx | 148 | ||||
| -rw-r--r-- | src/assets/react.svg | 1 | ||||
| -rw-r--r-- | src/components/ResultDisplay.tsx | 48 | ||||
| -rw-r--r-- | src/components/SizeSelector.tsx | 81 | ||||
| -rw-r--r-- | src/data/tire_sizes.json | 74 | ||||
| -rw-r--r-- | src/index.css | 70 | ||||
| -rw-r--r-- | src/types.ts | 26 | ||||
| -rw-r--r-- | src/utils/calculate_circumference.ts | 36 |
9 files changed, 384 insertions, 142 deletions
diff --git a/src/App.css b/src/App.css deleted file mode 100644 index b9d355d..0000000 --- a/src/App.css +++ /dev/null @@ -1,42 +0,0 @@ -#root { - max-width: 1280px; - margin: 0 auto; - padding: 2rem; - text-align: center; -} - -.logo { - height: 6em; - padding: 1.5em; - will-change: filter; - transition: filter 300ms; -} -.logo:hover { - filter: drop-shadow(0 0 2em #646cffaa); -} -.logo.react:hover { - filter: drop-shadow(0 0 2em #61dafbaa); -} - -@keyframes logo-spin { - from { - transform: rotate(0deg); - } - to { - transform: rotate(360deg); - } -} - -@media (prefers-reduced-motion: no-preference) { - a:nth-of-type(2) .logo { - animation: logo-spin infinite 20s linear; - } -} - -.card { - padding: 2em; -} - -.read-the-docs { - color: #888; -} diff --git a/src/App.tsx b/src/App.tsx index a062428..532597a 100644 --- a/src/App.tsx +++ b/src/App.tsx @@ -1,35 +1,123 @@ -import { useState } from 'react' -import reactLogo from './assets/react.svg' -import viteLogo from '/vite.svg' -import './App.css' +/** + * App.tsx — root component for the Bicycle Wheel Circumference calculator. + * + * State management: + * - Each selector (rim / tire) tracks two pieces of state: + * 1. The currently selected dropdown label (or "__custom__"). + * 2. The raw text-input value (kept as a string for UX). + * - When a dropdown option is chosen its diameter_mm fills the text input. + * - When the user types a number, we search for the first option whose + * diameter_mm matches; if none match we set the dropdown to "Custom". + * - The circumference result is derived (not stored) on every render. + */ -function App() { - const [count, setCount] = useState(0) +import { useState, useMemo } from "react"; +import tire_size_data from "./data/tire_sizes.json"; +import type { TireSizeData, SizeOption } from "./types"; +import SizeSelector, { CUSTOM_VALUE } from "./components/SizeSelector"; +import ResultDisplay from "./components/ResultDisplay"; +import { calculate_circumference } from "./utils/calculate_circumference"; +/** Typed reference to the imported JSON. */ +const data: TireSizeData = tire_size_data; + +/** + * Given a numeric value, find the first option whose diameter_mm matches. + * Returns the option's label, or CUSTOM_VALUE when nothing matches. + */ +function find_matching_option(value: number, options: SizeOption[]): string { + const match = options.find((o) => o.diameter_mm === value); + return match ? match.label : CUSTOM_VALUE; +} + +export default function App() { + /* ── Rim state ─────────────────────────────────────────────── */ + const [rim_option, set_rim_option] = useState<string>(""); + const [rim_input, set_rim_input] = useState<string>(""); + + /* ── Tire state ────────────────────────────────────────────── */ + const [tire_option, set_tire_option] = useState<string>(""); + const [tire_input, set_tire_input] = useState<string>(""); + + /* ── Derived circumference result ──────────────────────────── */ + const result = useMemo( + () => + calculate_circumference(parseFloat(rim_input), parseFloat(tire_input)), + [rim_input, tire_input], + ); + + /* ── Handlers: Rim ─────────────────────────────────────────── */ + const handle_rim_option = (label: string) => { + set_rim_option(label); + // When "Custom" is chosen, leave the text input alone. + if (label === CUSTOM_VALUE) return; + const match = data.wheel_sizes.find((o) => o.label === label); + if (match) set_rim_input(String(match.diameter_mm)); + }; + + const handle_rim_input = (raw: string) => { + set_rim_input(raw); + const num = parseFloat(raw); + if (isNaN(num)) { + set_rim_option(CUSTOM_VALUE); + return; + } + set_rim_option(find_matching_option(num, data.wheel_sizes)); + }; + + /* ── Handlers: Tire ────────────────────────────────────────── */ + const handle_tire_option = (label: string) => { + set_tire_option(label); + if (label === CUSTOM_VALUE) return; + const match = data.tire_sizes.find((o) => o.label === label); + if (match) set_tire_input(String(match.diameter_mm)); + }; + + const handle_tire_input = (raw: string) => { + set_tire_input(raw); + const num = parseFloat(raw); + if (isNaN(num)) { + set_tire_option(CUSTOM_VALUE); + return; + } + set_tire_option(find_matching_option(num, data.tire_sizes)); + }; + + /* ── Render ────────────────────────────────────────────────── */ return ( - <> - <div> - <a href="https://vite.dev" target="_blank"> - <img src={viteLogo} className="logo" alt="Vite logo" /> - </a> - <a href="https://react.dev" target="_blank"> - <img src={reactLogo} className="logo react" alt="React logo" /> - </a> - </div> - <h1 className="bg-red-500">Vite + React</h1> - <div className="card"> - <button onClick={() => setCount((count) => count + 1)}> - count is {count} - </button> - <p> - Edit <code>src/App.tsx</code> and save to test HMR - </p> + <div className="min-h-screen flex items-center justify-center p-4"> + <div className="card card-border bg-base-100 shadow-xl w-full max-w-lg"> + <div className="card-body gap-6"> + <h1 className="card-title justify-center text-2xl"> + Tire Size Calculator + </h1> + + {/* Rim size selector */} + <SizeSelector + label="Rim Size" + options={data.wheel_sizes} + selected_option={rim_option} + input_value={rim_input} + on_option_change={handle_rim_option} + on_input_change={handle_rim_input} + /> + + {/* Tire size selector */} + <SizeSelector + label="Tire Size" + options={data.tire_sizes} + selected_option={tire_option} + input_value={tire_input} + on_option_change={handle_tire_option} + on_input_change={handle_tire_input} + /> + + <div className="divider">Results</div> + + {/* Computed output */} + <ResultDisplay result={result} /> + </div> </div> - <p className="read-the-docs"> - Click on the Vite and React logos to learn more - </p> - </> - ) + </div> + ); } - -export default App diff --git a/src/assets/react.svg b/src/assets/react.svg deleted file mode 100644 index 6c87de9..0000000 --- a/src/assets/react.svg +++ /dev/null @@ -1 +0,0 @@ -<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" aria-hidden="true" role="img" class="iconify iconify--logos" width="35.93" height="32" preserveAspectRatio="xMidYMid meet" viewBox="0 0 256 228"><path fill="#00D8FF" d="M210.483 73.824a171.49 171.49 0 0 0-8.24-2.597c.465-1.9.893-3.777 1.273-5.621c6.238-30.281 2.16-54.676-11.769-62.708c-13.355-7.7-35.196.329-57.254 19.526a171.23 171.23 0 0 0-6.375 5.848a155.866 155.866 0 0 0-4.241-3.917C100.759 3.829 77.587-4.822 63.673 3.233C50.33 10.957 46.379 33.89 51.995 62.588a170.974 170.974 0 0 0 1.892 8.48c-3.28.932-6.445 1.924-9.474 2.98C17.309 83.498 0 98.307 0 113.668c0 15.865 18.582 31.778 46.812 41.427a145.52 145.52 0 0 0 6.921 2.165a167.467 167.467 0 0 0-2.01 9.138c-5.354 28.2-1.173 50.591 12.134 58.266c13.744 7.926 36.812-.22 59.273-19.855a145.567 145.567 0 0 0 5.342-4.923a168.064 168.064 0 0 0 6.92 6.314c21.758 18.722 43.246 26.282 56.54 18.586c13.731-7.949 18.194-32.003 12.4-61.268a145.016 145.016 0 0 0-1.535-6.842c1.62-.48 3.21-.974 4.76-1.488c29.348-9.723 48.443-25.443 48.443-41.52c0-15.417-17.868-30.326-45.517-39.844Zm-6.365 70.984c-1.4.463-2.836.91-4.3 1.345c-3.24-10.257-7.612-21.163-12.963-32.432c5.106-11 9.31-21.767 12.459-31.957c2.619.758 5.16 1.557 7.61 2.4c23.69 8.156 38.14 20.213 38.14 29.504c0 9.896-15.606 22.743-40.946 31.14Zm-10.514 20.834c2.562 12.94 2.927 24.64 1.23 33.787c-1.524 8.219-4.59 13.698-8.382 15.893c-8.067 4.67-25.32-1.4-43.927-17.412a156.726 156.726 0 0 1-6.437-5.87c7.214-7.889 14.423-17.06 21.459-27.246c12.376-1.098 24.068-2.894 34.671-5.345a134.17 134.17 0 0 1 1.386 6.193ZM87.276 214.515c-7.882 2.783-14.16 2.863-17.955.675c-8.075-4.657-11.432-22.636-6.853-46.752a156.923 156.923 0 0 1 1.869-8.499c10.486 2.32 22.093 3.988 34.498 4.994c7.084 9.967 14.501 19.128 21.976 27.15a134.668 134.668 0 0 1-4.877 4.492c-9.933 8.682-19.886 14.842-28.658 17.94ZM50.35 144.747c-12.483-4.267-22.792-9.812-29.858-15.863c-6.35-5.437-9.555-10.836-9.555-15.216c0-9.322 13.897-21.212 37.076-29.293c2.813-.98 5.757-1.905 8.812-2.773c3.204 10.42 7.406 21.315 12.477 32.332c-5.137 11.18-9.399 22.249-12.634 32.792a134.718 134.718 0 0 1-6.318-1.979Zm12.378-84.26c-4.811-24.587-1.616-43.134 6.425-47.789c8.564-4.958 27.502 2.111 47.463 19.835a144.318 144.318 0 0 1 3.841 3.545c-7.438 7.987-14.787 17.08-21.808 26.988c-12.04 1.116-23.565 2.908-34.161 5.309a160.342 160.342 0 0 1-1.76-7.887Zm110.427 27.268a347.8 347.8 0 0 0-7.785-12.803c8.168 1.033 15.994 2.404 23.343 4.08c-2.206 7.072-4.956 14.465-8.193 22.045a381.151 381.151 0 0 0-7.365-13.322Zm-45.032-43.861c5.044 5.465 10.096 11.566 15.065 18.186a322.04 322.04 0 0 0-30.257-.006c4.974-6.559 10.069-12.652 15.192-18.18ZM82.802 87.83a323.167 323.167 0 0 0-7.227 13.238c-3.184-7.553-5.909-14.98-8.134-22.152c7.304-1.634 15.093-2.97 23.209-3.984a321.524 321.524 0 0 0-7.848 12.897Zm8.081 65.352c-8.385-.936-16.291-2.203-23.593-3.793c2.26-7.3 5.045-14.885 8.298-22.6a321.187 321.187 0 0 0 7.257 13.246c2.594 4.48 5.28 8.868 8.038 13.147Zm37.542 31.03c-5.184-5.592-10.354-11.779-15.403-18.433c4.902.192 9.899.29 14.978.29c5.218 0 10.376-.117 15.453-.343c-4.985 6.774-10.018 12.97-15.028 18.486Zm52.198-57.817c3.422 7.8 6.306 15.345 8.596 22.52c-7.422 1.694-15.436 3.058-23.88 4.071a382.417 382.417 0 0 0 7.859-13.026a347.403 347.403 0 0 0 7.425-13.565Zm-16.898 8.101a358.557 358.557 0 0 1-12.281 19.815a329.4 329.4 0 0 1-23.444.823c-7.967 0-15.716-.248-23.178-.732a310.202 310.202 0 0 1-12.513-19.846h.001a307.41 307.41 0 0 1-10.923-20.627a310.278 310.278 0 0 1 10.89-20.637l-.001.001a307.318 307.318 0 0 1 12.413-19.761c7.613-.576 15.42-.876 23.31-.876H128c7.926 0 15.743.303 23.354.883a329.357 329.357 0 0 1 12.335 19.695a358.489 358.489 0 0 1 11.036 20.54a329.472 329.472 0 0 1-11 20.722Zm22.56-122.124c8.572 4.944 11.906 24.881 6.52 51.026c-.344 1.668-.73 3.367-1.15 5.09c-10.622-2.452-22.155-4.275-34.23-5.408c-7.034-10.017-14.323-19.124-21.64-27.008a160.789 160.789 0 0 1 5.888-5.4c18.9-16.447 36.564-22.941 44.612-18.3ZM128 90.808c12.625 0 22.86 10.235 22.86 22.86s-10.235 22.86-22.86 22.86s-22.86-10.235-22.86-22.86s10.235-22.86 22.86-22.86Z"></path></svg>
\ No newline at end of file diff --git a/src/components/ResultDisplay.tsx b/src/components/ResultDisplay.tsx new file mode 100644 index 0000000..3f3f81a --- /dev/null +++ b/src/components/ResultDisplay.tsx @@ -0,0 +1,48 @@ +/** + * ResultDisplay.tsx + * + * Shows the computed circumference in several units inside a styled card. + * When inputs are incomplete / invalid the component shows a helpful prompt. + */ + +import type { CircumferenceResult } from "../types"; + +interface ResultDisplayProps { + result: CircumferenceResult | null; +} + +export default function ResultDisplay({ result }: ResultDisplayProps) { + if (!result) { + return ( + <div className="card card-border bg-base-200"> + <div className="card-body items-center text-center"> + <p className="text-base-content/60"> + Select or enter both rim and tire sizes to see the circumference. + </p> + </div> + </div> + ); + } + + /** Helper to render a single stat inside the stats bar. */ + const stat_item = (title: string, value: string | number, desc: string) => ( + <div className="stat" key={title}> + <div className="stat-title">{title}</div> + <div className="stat-value text-lg">{value}</div> + <div className="stat-desc">{desc}</div> + </div> + ); + + return ( + <div className="card card-border bg-base-200"> + <div className="card-body"> + <h2 className="card-title justify-center">Wheel Circumference</h2> + <div className="stats stats-vertical sm:stats-horizontal shadow w-full"> + {stat_item("Millimeters", result.mm, "mm")} + {stat_item("Centimeters", result.cm, "cm")} + {stat_item("Inches", result.inches, "in")} + </div> + </div> + </div> + ); +} diff --git a/src/components/SizeSelector.tsx b/src/components/SizeSelector.tsx new file mode 100644 index 0000000..cb4baef --- /dev/null +++ b/src/components/SizeSelector.tsx @@ -0,0 +1,81 @@ +/** + * SizeSelector.tsx + * + * A reusable pair of <select> + <input> for choosing a rim or tire size. + * + * Behaviour: + * - Selecting a dropdown option fills the text input with its diameter_mm. + * - Typing a number in the text input auto-selects the first matching + * dropdown option, or falls back to "Custom" if no match exists. + * - Choosing "Custom" in the dropdown does nothing to the text input. + */ + +import type { SizeOption } from "../types"; + +/** Sentinel value used as the <option> value for "Custom". */ +const CUSTOM_VALUE = "__custom__"; + +interface SizeSelectorProps { + /** Human-readable label shown above the controls. */ + label: string; + /** The list of predefined size options to populate the dropdown. */ + options: SizeOption[]; + /** Currently selected dropdown value (a label string or CUSTOM_VALUE). */ + selected_option: string; + /** Current numeric value in the text input (as a string so we can allow empty). */ + input_value: string; + /** Called when the dropdown selection changes. */ + on_option_change: (option_value: string) => void; + /** Called when the text input value changes. */ + on_input_change: (value: string) => void; +} + +export default function SizeSelector({ + label, + options, + selected_option, + input_value, + on_option_change, + on_input_change, +}: SizeSelectorProps) { + return ( + <fieldset className="fieldset"> + <legend className="fieldset-legend">{label}</legend> + + {/* Dropdown for predefined sizes */} + <select + className="select select-bordered w-full" + value={selected_option} + aria-label={`${label} preset`} + onChange={(e) => on_option_change(e.target.value)} + > + <option disabled value=""> + Pick a size + </option> + {options.map((opt, idx) => ( + <option key={`${opt.label}-${idx}`} value={opt.label}> + {opt.label} ({opt.diameter_mm} mm) + </option> + ))} + <option value={CUSTOM_VALUE}>Custom</option> + </select> + + {/* Numeric text input — mirrors / overrides the dropdown */} + <label className="input w-full mt-2"> + <input + type="number" + step="any" + min="0" + className="grow" + placeholder="mm" + value={input_value} + aria-label={`${label} diameter in mm`} + onChange={(e) => on_input_change(e.target.value)} + /> + <span className="label">mm</span> + </label> + </fieldset> + ); +} + +export { CUSTOM_VALUE }; diff --git a/src/data/tire_sizes.json b/src/data/tire_sizes.json new file mode 100644 index 0000000..d101fc8 --- /dev/null +++ b/src/data/tire_sizes.json @@ -0,0 +1,74 @@ +{ + "wheel_sizes": [ + { "label": "12.5\"", "diameter_mm": 203 }, + { "label": "14\"", "diameter_mm": 254 }, + { "label": "16\"", "diameter_mm": 305 }, + { "label": "20\"", "diameter_mm": 406 }, + { "label": "24\" BMX/Kids Bikes", "diameter_mm": 507 }, + { "label": "24\" Terry Bicycles", "diameter_mm": 520 }, + { "label": "24\"", "diameter_mm": 540 }, + { "label": "24\" Schwinn", "diameter_mm": 540 }, + { "label": "26\"", "diameter_mm": 559 }, + { "label": "650c", "diameter_mm": 571 }, + { "label": "650b", "diameter_mm": 584 }, + { "label": "27.5", "diameter_mm": 584 }, + { "label": "26 x 1 1/2\"", "diameter_mm": 584 }, + { "label": "650a", "diameter_mm": 590 }, + { "label": "26 x 1 3/8\"", "diameter_mm": 590 }, + { "label": "650", "diameter_mm": 597 }, + { "label": "26 x 1 1/4\"", "diameter_mm": 597 }, + { "label": "29er", "diameter_mm": 622 }, + { "label": "700c", "diameter_mm": 622 }, + { "label": "27 inch", "diameter_mm": 630 } + ], + "tire_sizes": [ + { "label": "18C", "diameter_mm": 18 }, + { "label": "19C", "diameter_mm": 19 }, + { "label": "20C", "diameter_mm": 20 }, + { "label": "21C", "diameter_mm": 21 }, + { "label": "23C", "diameter_mm": 23 }, + { "label": "25C", "diameter_mm": 25 }, + { "label": "26C", "diameter_mm": 26 }, + { "label": "28C", "diameter_mm": 28 }, + { "label": "30C", "diameter_mm": 30 }, + { "label": "32C", "diameter_mm": 32 }, + { "label": "35C", "diameter_mm": 35 }, + { "label": "38C", "diameter_mm": 38 }, + { "label": "40C", "diameter_mm": 40 }, + { "label": "44C", "diameter_mm": 44 }, + { "label": "50C", "diameter_mm": 50 }, + { "label": "56C", "diameter_mm": 56 }, + { "label": "1.00 inch", "diameter_mm": 25.4 }, + { "label": "1 1/8 inch", "diameter_mm": 28.575 }, + { "label": "1.25 inch", "diameter_mm": 31.75 }, + { "label": "1 3/8 inch", "diameter_mm": 34.925 }, + { "label": "1.4 inch", "diameter_mm": 35.56 }, + { "label": "1.5 inch", "diameter_mm": 38.1 }, + { "label": "1.75 inch", "diameter_mm": 44.45 }, + { "label": "1.95 inch", "diameter_mm": 49.5 }, + { "label": "2.00 inch", "diameter_mm": 50.8 }, + { "label": "2.10 inch", "diameter_mm": 53.34 }, + { "label": "2.125 inch", "diameter_mm": 54 }, + { "label": "2.20 inch", "diameter_mm": 55.88 }, + { "label": "2.25 inch", "diameter_mm": 57.15 }, + { "label": "2.30 inch", "diameter_mm": 58.42 }, + { "label": "2.35 inch", "diameter_mm": 59.69 }, + { "label": "2.40 inch", "diameter_mm": 60.69 }, + { "label": "2.50 inch", "diameter_mm": 63.5 }, + { "label": "2.60 inch", "diameter_mm": 66.04 }, + { "label": "2.70 inch", "diameter_mm": 68.58 }, + { "label": "2.80 inch", "diameter_mm": 71.12 }, + { "label": "2.90 inch", "diameter_mm": 73.66 }, + { "label": "3.0 inch", "diameter_mm": 76.2 }, + { "label": "3.1 inch", "diameter_mm": 78.74 }, + { "label": "3.2 inch", "diameter_mm": 81.28 }, + { "label": "3.3 inch", "diameter_mm": 83.82 }, + { "label": "3.4 inch", "diameter_mm": 86.36 }, + { "label": "3.5 inch", "diameter_mm": 88.9 }, + { "label": "3.6 inch", "diameter_mm": 91.44 }, + { "label": "3.7 inch", "diameter_mm": 93.98 }, + { "label": "3.8 inch", "diameter_mm": 96.52 }, + { "label": "3.9 inch", "diameter_mm": 99.06 }, + { "label": "4.0 inch", "diameter_mm": 101.6 } + ] +} diff --git a/src/index.css b/src/index.css index 34900d7..91f6dbe 100644 --- a/src/index.css +++ b/src/index.css @@ -1,71 +1,3 @@ +/* Tailwind CSS base + daisyUI plugin — all styling is done via utility classes */ @import "tailwindcss"; @plugin "daisyui"; - -:root { - font-family: system-ui, Avenir, Helvetica, Arial, sans-serif; - line-height: 1.5; - font-weight: 400; - - color-scheme: light dark; - color: rgba(255, 255, 255, 0.87); - background-color: #242424; - - font-synthesis: none; - text-rendering: optimizeLegibility; - -webkit-font-smoothing: antialiased; - -moz-osx-font-smoothing: grayscale; -} - -a { - font-weight: 500; - color: #646cff; - text-decoration: inherit; -} -a:hover { - color: #535bf2; -} - -body { - margin: 0; - display: flex; - place-items: center; - min-width: 320px; - min-height: 100vh; -} - -h1 { - font-size: 3.2em; - line-height: 1.1; -} - -button { - border-radius: 8px; - border: 1px solid transparent; - padding: 0.6em 1.2em; - font-size: 1em; - font-weight: 500; - font-family: inherit; - background-color: #1a1a1a; - cursor: pointer; - transition: border-color 0.25s; -} -button:hover { - border-color: #646cff; -} -button:focus, -button:focus-visible { - outline: 4px auto -webkit-focus-ring-color; -} - -@media (prefers-color-scheme: light) { - :root { - color: #213547; - background-color: #ffffff; - } - a:hover { - color: #747bff; - } - button { - background-color: #f9f9f9; - } -} diff --git a/src/types.ts b/src/types.ts new file mode 100644 index 0000000..75d6945 --- /dev/null +++ b/src/types.ts @@ -0,0 +1,26 @@ +/** + * Type definitions for the tire size data used throughout the app. + * Each size entry has a human-readable label and a diameter in millimeters. + */ + +/** A single rim or tire size option from our reference data. */ +export interface SizeOption { + label: string; + diameter_mm: number; +} + +/** The shape of the imported tire_sizes.json file. */ +export interface TireSizeData { + wheel_sizes: SizeOption[]; + tire_sizes: SizeOption[]; +} + +/** + * Results from the circumference calculation. + * All values derived from: circumference = 3.13772 * (2 * tire + rim) + */ +export interface CircumferenceResult { + mm: number; + cm: number; + inches: number; +} diff --git a/src/utils/calculate_circumference.ts b/src/utils/calculate_circumference.ts new file mode 100644 index 0000000..4ef6a2f --- /dev/null +++ b/src/utils/calculate_circumference.ts @@ -0,0 +1,36 @@ +/** + * calculate_circumference.ts + * + * Pure function that computes the bicycle wheel circumference from rim and + * tire diameters (both in mm). The formula uses 3.13772 instead of exact π + * to approximate the "roll-out" circumference (tire compressed under rider + * weight). + * + * Formula: circumference_mm = 3.13772 × (2 × tire_diameter + rim_diameter) + */ + +import type { CircumferenceResult } from "../types"; + +/** The modified Pi constant that accounts for tire compression. */ +const ROLLOUT_PI = 3.13772; + +/** + * Returns circumference in multiple units, or null when inputs are invalid + * (non-positive or missing). + */ +export function calculate_circumference( + rim_mm: number, + tire_mm: number, +): CircumferenceResult | null { + if (rim_mm <= 0 || tire_mm <= 0 || isNaN(rim_mm) || isNaN(tire_mm)) { + return null; + } + + const circ_mm = ROLLOUT_PI * (2 * tire_mm + rim_mm); + + return { + mm: Math.round(circ_mm), + cm: Math.round(circ_mm / 10), + inches: Math.round((10 * circ_mm) / 25.4) / 10, + }; +} |
