X-Git-Url: https://git.ladys.computer/Pisces/blobdiff_plain/32e1e0ba06627f2ed6c3f99c415ef6b9c0f7de4d..edbef3a179c4404eb02a83860a76c1f11b9b63d2:/iri.js?ds=inline diff --git a/iri.js b/iri.js new file mode 100644 index 0000000..f1abe78 --- /dev/null +++ b/iri.js @@ -0,0 +1,372 @@ +// ♓🌟 Piscēs ∷ iri.js +// ==================================================================== +// +// Copyright © 2020, 2022 Lady [@ Lady’s Computer]. +// +// This Source Code Form is subject to the terms of the Mozilla Public +// License, v. 2.0. If a copy of the MPL was not distributed with this +// file, You can obtain one at . + +const sub·delims = String.raw`[!\$&'()*+,;=]`; +const gen·delims = String.raw`[:/?#\[\]@]`; +//deno-lint-ignore no-unused-vars +const reserved = String.raw`${gen·delims}|${sub·delims}`; +const unreserved = String.raw`[A-Za-z0-9\-\._~]`; +const pct·encoded = String.raw`%[0-9A-Fa-f][0-9A-Fa-f]`; +const dec·octet = String.raw + `[0-9]|[1-9][0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5]`; +const IPv4address = String.raw + `(?:${dec·octet})\.(?:${dec·octet})\.(?:${dec·octet})\.(?:${dec·octet})`; +const h16 = String.raw`[0-9A-Fa-f]{1,4}`; +const ls32 = String.raw`(?:${h16}):(?:${h16})|${IPv4address}`; +const IPv6address = String.raw + `(?:(?:${h16}):){6}(?:${ls32})|::(?:(?:${h16}):){5}(?:${ls32})|(?:${h16})?::(?:(?:${h16}):){4}(?:${ls32})|(?:(?:(?:${h16}):){0,1}(?:${h16}))?::(?:(?:${h16}):){3}(?:${ls32})|(?:(?:(?:${h16}):){0,2}(?:${h16}))?::(?:(?:${h16}):){2}(?:${ls32})|(?:(?:(?:${h16}):){0,3}(?:${h16}))?::(?:${h16}):(?:${ls32})|(?:(?:(?:${h16}):){0,4}(?:${h16}))?::(?:${ls32})|(?:(?:(?:${h16}):){0,5}(?:${h16}))?::(?:${h16})|(?:(?:(?:${h16}):){0,6}(?:${h16}))?::`; +const IPvFuture = String.raw + `v[0-9A-Fa-f]{1,}\.(?:${unreserved}|${sub·delims}|:)`; +const IP·literal = String.raw`\[(?:${IPv6address}|${IPvFuture})\]`; +const port = String.raw`[0-9]*`; +const scheme = String.raw`[A-Za-z][A-Za-z0-9+\-\.]*`; +const pchar = String.raw + `${unreserved}|${pct·encoded}|${sub·delims}|[:@]`; +const fragment = String.raw`(?:${pchar}|[/?])*`; +const query = String.raw`(?:${pchar}|[/?])*`; +const segment·nz·nc = String.raw + `(?:${unreserved}|${pct·encoded}|${sub·delims}|@)+`; +const segment·nz = String.raw`(?:${pchar})+`; +const segment = String.raw`(?:${pchar})*`; +const path·empty = String.raw``; +const path·rootless = String.raw + `(?:${segment·nz})(?:/(?:${segment}))*`; +const path·noscheme = String.raw + `(?:${segment·nz·nc})(?:/(?:${segment}))*`; +const path·absolute = String.raw + `/(?:(?:${segment·nz})(?:/(?:${segment}))*)?`; +const path·abempty = String.raw`(?:/(?:${segment}))*`; +//deno-lint-ignore no-unused-vars +const path = String.raw + `${path·abempty}|${path·absolute}|${path·noscheme}|${path·rootless}|${path·empty}`; +const reg·name = String.raw + `(?:${unreserved}|${pct·encoded}|${sub·delims})*`; +const host = String.raw`${IP·literal}|${IPv4address}|${reg·name}`; +const userinfo = String.raw + `(?:${unreserved}|${pct·encoded}|${sub·delims}|:)*`; +const authority = String.raw + `(?:(?:${userinfo})@)?(?:${host})(?::(?:${port}))?`; +const relative·part = String.raw + `//(?:${authority})(?:${path·abempty})|(?:${path·absolute})|(?:${path·noscheme})|(?:${path·empty})`; +const relative·ref = String.raw + `(?:${relative·part})(?:\?(?:${query}))?(?:#(?:${fragment}))?`; +const hier·part = String.raw + `//(?:${authority})(?:${path·abempty})|(?:${path·absolute})|(?:${path·rootless})|(?:${path·empty})`; +const absolute·URI = String.raw + `(?:${scheme}):(?:${hier·part})(?:\?(?:${query}))?`; +const URI = String.raw + `(?:${scheme}):(?:${hier·part})(?:\?(?:${query}))?(?:#(?:${fragment}))?`; +const URI·reference = String.raw`(?:${URI})|(?:${relative·ref})`; + +const iprivate = String.raw + `[\u{E000}-\u{F8FF}\u{F0000}-\u{FFFFD}\u{100000}-\u{10FFFD}]`; +const ucschar = String.raw + `[\u{A0}-\u{D7FF}\u{F900}-\u{FDCF}\u{FDF0}-\u{FFEF}\u{10000}-\u{1FFFD}\u{20000}-\u{2FFFD}\u{30000}-\u{3FFFD}\u{40000}-\u{4FFFD}\u{50000}-\u{5FFFD}\u{60000}-\u{6FFFD}\u{70000}-\u{7FFFD}\u{80000}-\u{8FFFD}\u{90000}-\u{9FFFD}\u{A0000}-\u{AFFFD}\u{B0000}-\u{BFFFD}\u{C0000}-\u{CFFFD}\u{D0000}-\u{DFFFD}\u{E0000}-\u{EFFFD}]`; +const iunreserved = String.raw`[A-Za-z0-9\-\._~]|${ucschar}`; +const ipchar = String.raw + `${iunreserved}|${pct·encoded}|${sub·delims}|[:@]`; +const ifragment = String.raw`(?:${ipchar}|[/?])*`; +const iquery = String.raw`(?:${ipchar}|${iprivate}|[/?])*`; +const isegment·nz·nc = String.raw + `(?:${iunreserved}|${pct·encoded}|${sub·delims}|@)+`; +const isegment·nz = String.raw`(?:${ipchar})+`; +const isegment = String.raw`(?:${ipchar})*`; +const ipath·empty = String.raw``; +const ipath·rootless = String.raw + `(?:${isegment·nz})(?:/(?:${isegment}))*`; +const ipath·noscheme = String.raw + `(?:${isegment·nz·nc})(?:/(?:${isegment}))*`; +const ipath·absolute = String.raw + `/(?:(?:${isegment·nz})(?:/(?:${isegment}))*)?`; +const ipath·abempty = String.raw`(?:/(?:${isegment}))*`; +//deno-lint-ignore no-unused-vars +const ipath = String.raw + `${ipath·abempty}|${ipath·absolute}|${ipath·noscheme}|${ipath·rootless}|${ipath·empty}`; +const ireg·name = String.raw + `(?:${iunreserved}|${pct·encoded}|${sub·delims})*`; +const ihost = String.raw`${IP·literal}|${IPv4address}|${ireg·name}`; +const iuserinfo = String.raw + `(?:${iunreserved}|${pct·encoded}|${sub·delims}|:)*`; +const iauthority = String.raw + `(?:(?:${iuserinfo})@)?(?:${ihost})(?::(?:${port}))?`; +const irelative·part = String.raw + `//(?:${iauthority})(?:${ipath·abempty})|(?:${ipath·absolute})|(?:${ipath·noscheme})|(?:${ipath·empty})`; +const irelative·ref = String.raw + `(?:${irelative·part})(?:\?(?:${iquery}))?(?:#(?:${ifragment}))?`; +const ihier·part = String.raw + `//(?:${iauthority})(?:${ipath·abempty})|(?:${ipath·absolute})|(?:${ipath·rootless})|(?:${ipath·empty})`; +const absolute·IRI = String.raw + `(?:${scheme}):(?:${ihier·part})(?:\?(?:${iquery}))?`; +const IRI = String.raw + `(?:${scheme}):(?:${ihier·part})(?:\?(?:${iquery}))?(?:#(?:${ifragment}))?`; +const IRI·reference = String.raw`(?:${IRI})|(?:${irelative·ref})`; + +export const { + isAbsoluteURI, // U·R·I with no fragment + isURI, + isURIReference, + isAbsoluteIRI, // I·R·I with no fragment + isIRI, + isIRIReference, +} = Object.fromEntries( + Object.entries({ + isAbsoluteIRI: absolute·IRI, + isAbsoluteURI: absolute·URI, + isIRI: IRI, + isIRIReference: IRI·reference, + isURI: URI, + isURIReference: URI·reference, + }).map(([key, value]) => { + const regExp = new RegExp(`^(?:${value})$`, "u"); + return [ + key, + Object.defineProperties( + ($) => typeof $ == "string" && regExp.test($), + { + name: { value: key }, + [Symbol.match]: { + configurable: true, + enumerable: false, + get: () => regExp[Symbol.match].bind(regExp), + set: undefined, + }, + }, + ), + ]; + }), +); + +/** + * Recomposes an I·R·I reference from its component parts. + * + * See §5.3 of R·F·C 3986. + */ +export const composeReference = ($) => { + const result = []; + const { scheme, authority, path, query, fragment } = $; + if (scheme != null) { + result.push(scheme, ":"); + } else { + /* do nothing */ + } + if (authority != null) { + result.push("//", authority); + } else { + /* do nothing */ + } + result.push(path ?? ""); + if (query != null) { + result.push("?", query); + } else { + /* do nothing */ + } + if (fragment != null) { + result.push("#", fragment); + } else { + /* do nothing */ + } + return result.join(""); +}; + +/** + * Converts an I·R·I to the corresponding U·R·I by percent‐encoding + * unsupported characters. + * + * This does not punycode the authority. + */ +export const iri2uri = ($) => + [...function* () { + const encoder = new TextEncoder(); + for (const character of $) { + if (new RegExp(`${ucschar}|${iprivate}`, "u").test(character)) { + for (const byte of encoder.encode(character)) { + yield `%${byte.toString(0x10).toUpperCase()}`; + } + } else { + yield character; + } + } + }()].join(""); + +/** + * Merges a reference path with a base path. + * + * See §5.2.3 of R·F·C 3986. + */ +export const mergePaths = (base, reference) => { + const baseStr = `${base}`; + return `${ + baseStr.substring(0, baseStr.lastIndexOf("/") + 1) + }${reference}`; +}; + +/** + * Returns the `scheme`, `authority`, `path`, `query`, and `fragment` + * of the provided I·R·I reference. + */ +export const parseReference = ($) => { + const regExp = new RegExp( + String.raw + `^(?:(?${scheme}):(?://(?${iauthority})(?${ipath·abempty})|(?(?:${ipath·absolute})|(?:${ipath·rootless})|(?:${ipath·empty})))(?:\?(?${iquery}))?(?:#(?${ifragment}))?|(?://(?${iauthority})(?${ipath·abempty})|(?(?:${ipath·absolute})|(?:${ipath·noscheme})|(?:${ipath·empty})))(?:\?(?${iquery}))?(?:#(?${ifragment}))?)$`, + "u", + ); + const { + absolute·scheme, + absolute·authority, + absolute·patha, + absolute·pathb, + absolute·query, + absolute·fragment, + relative·authority, + relative·patha, + relative·pathb, + relative·query, + relative·fragment, + } = regExp.exec($)?.groups ?? {}; + return { + scheme: absolute·scheme, + authority: absolute·authority ?? relative·authority, + path: absolute·patha ?? absolute·pathb ?? relative·patha ?? + relative·pathb, + query: absolute·query ?? relative·query, + fragment: absolute·fragment ?? relative·fragment, + }; +}; + +/** + * Removes all dot segments ("." or "..") from the provided I·R·I. + * + * See §5.2.4 of R·F·C 3986. + */ +export const removeDotSegments = ($) => { + const input = `${$}`; + const output = []; + const { length } = input; + let index = 0; + while (index < length) { + if (input.startsWith("../", index)) { + // The input starts with a double leader; drop it. This can only + // occur at the beginning of the input. + index += 3; + } else if (input.startsWith("./", index)) { + // The input starts with a single leader; drop it. This can only + // occur at the beginning of the input. + index += 2; + } else if (input.startsWith("/./", index)) { + // The input starts with a slash, single leader, and another + // slash. Ignore it, and move the input to just before the second + // slash. + index += 2; + } else if (input.startsWith("/.", index) && index + 2 == length) { + // The input starts with a slash and single leader, and this + // exhausts the string. Push an empty segment and move the index + // to the end of the string. + output.push("/"); + index = length; + } else if (input.startsWith("/../", index)) { + // The input starts with a slash, double leader, and another + // slash. Drop a segment from the output, and move the input to + // just before the second slash. + index += 3; + output.splice(-1, 1); + } else if (input.startsWith("/..", index) && index + 3 == length) { + // The input starts with a slash and single leader, and this + // exhausts the string. Drop a segment from the output, push an + // empty segment, and move the index to the end of the string. + output.splice(-1, 1, "/"); + index = length; + } else if ( + input.startsWith(".", index) && index + 1 == length || + input.startsWith("..", index) && index + 2 == length + ) { + // The input starts with a single or double leader, and this + // exhausts the string. Do nothing (this can only occur at the + // beginning of input) and move the index to the end of the + // string. + index = length; + } else { + // The input does not start with a leader. Advance the index to + // the position before the next slash and push the segment + // between the old and new positions. + const nextIndex = input.indexOf("/", index + 1); + if (nextIndex == -1) { + // No slash remains; set index to the end of the string. + output.push(input.substring(index)); + index = length; + } else { + // There are further path segments. + output.push(input.substring(index, nextIndex)); + index = nextIndex; + } + } + } + return output.join(""); +}; + +/** + * Resolves the provided reference relative to the provided base I·R·I. + * + * See §5.2 of R·F·C 3986. + */ +export const resolveReference = (R, Base = location ?? "") => { + const { + scheme: Base·scheme, + authority: Base·authority, + path: Base·path, + query: Base·query, + } = parseReference(Base); + if (Base·scheme == null) { + throw new TypeError( + `Piscēs: Base I·R·I did not have a scheme: ${Base}.`, + ); + } else { + const { + scheme: R·scheme, + authority: R·authority, + path: R·path, + query: R·query, + fragment: R·fragment, + } = parseReference(R); + return composeReference( + R·scheme != null + ? { + scheme: R·scheme, + authority: R·authority, + path: removeDotSegments(R·path), + query: R·query, + fragment: R·fragment, + } + : R·authority != null + ? { + scheme: Base·scheme, + authority: R·authority, + path: removeDotSegments(R·path), + query: R·query, + fragment: R·fragment, + } + : !R·path + ? { + scheme: Base·scheme, + authority: Base·authority, + path: Base·path, + query: R·query ?? Base·query, + fragment: R·fragment, + } + : { + scheme: Base·scheme, + authority: Base·authority, + path: R·path[0] == "/" + ? removeDotSegments(R·path) + : removeDotSegments(mergePaths(Base·path || "/", R·path)), + query: R·query, + fragment: R·fragment, + }, + ); + } +};