feat: new dynamic path matcher

Author: posva

packages/router/src/new-route-resolver/matcher-pattern.ts

@@ -1,4 +1,4 @@
-import { MatcherName, MatcherQueryParams } from './matcher'
+import { decode, MatcherName, MatcherQueryParams } from './matcher'
 import { EmptyParams, MatcherParamsFormatted } from './matcher-location'
 import { miss } from './matchers/errors'
 
@@ -19,14 +19,28 @@ export interface MatcherPatternParams_Base<
   TIn = string,
   TOut extends MatcherParamsFormatted = MatcherParamsFormatted
 > {
+  /**
+   * Matches a serialized params value against the pattern.
+   *
+   * @param value - params value to parse
+   * @throws {MatchMiss} if the value doesn't match
+   * @returns parsed params
+   */
   match(value: TIn): TOut
+
+  /**
+   * Build a serializable value from parsed params. Should apply encoding if the
+   * returned value is a string (e.g path and hash should be encoded but query
+   * shouldn't).
+   *
+   * @param value - params value to parse
+   */
   build(params: TOut): TIn
 }
 
 export interface MatcherPatternPath<
-  TParams extends MatcherParamsFormatted = // | undefined // | void // so it might be a bit more convenient // TODO: should we allow to not return anything? It's valid to spread null and undefined
-  // | null
-  MatcherParamsFormatted
+  // TODO: should we allow to not return anything? It's valid to spread null and undefined
+  TParams extends MatcherParamsFormatted = MatcherParamsFormatted // | null // | undefined // | void // so it might be a bit more convenient
 > extends MatcherPatternParams_Base<string, TParams> {}
 
 export class MatcherPatternPathStatic
@@ -48,6 +62,143 @@ export class MatcherPatternPathStatic
 // example of a static matcher built at runtime
 // new MatcherPatternPathStatic('/')
 
+export interface Param_GetSet<
+  TIn extends string | string[] = string | string[],
+  TOut = TIn
+> {
+  get?: (value: NoInfer<TIn>) => TOut
+  set?: (value: NoInfer<TOut>) => TIn
+}
+
+export type ParamParser_Generic =
+  | Param_GetSet<string, any>
+  | Param_GetSet<string[], any>
+// TODO: these are possible values for optional params
+// | null | undefined
+
+/**
+ * Type safe helper to define a param parser.
+ *
+ * @param parser - the parser to define. Will be returned as is.
+ */
+/*! #__NO_SIDE_EFFECTS__ */
+export function defineParamParser<TOut, TIn extends string | string[]>(parser: {
+  get?: (value: TIn) => TOut
+  set?: (value: TOut) => TIn
+}): Param_GetSet<TIn, TOut> {
+  return parser
+}
+
+const PATH_PARAM_DEFAULT_GET = (value: string | string[]) => value
+const PATH_PARAM_DEFAULT_SET = (value: unknown) =>
+  value && Array.isArray(value) ? value.map(String) : String(value)
+// TODO: `(value an null | undefined)` for types
+
+/**
+ * NOTE: I tried to make this generic and infer the types from the params but failed. This is what I tried:
+ * ```ts
+ * export type ParamsFromParsers<P extends Record<string, ParamParser_Generic>> = {
+ *   [K in keyof P]: P[K] extends Param_GetSet<infer TIn, infer TOut>
+ *     ? unknown extends TOut // if any or unknown, use the value of TIn, which defaults to string | string[]
+ *       ? TIn
+ *       : TOut
+ *     : never
+ * }
+ *
+ * export class MatcherPatternPathDynamic<
+ *   ParamsParser extends Record<string, ParamParser_Generic>
+ * > implements MatcherPatternPath<ParamsFromParsers<ParamsParser>>
+ * {
+ *   private params: Record<string, Required<ParamParser_Generic>> = {}
+ *   constructor(
+ *     private re: RegExp,
+ *     params: ParamsParser,
+ *     public build: (params: ParamsFromParsers<ParamsParser>) => string
+ *     ) {}
+ * ```
+ * It ended up not working in one place or another. It could probably be fixed by
+ */
+
+export type ParamsFromParsers<P extends Record<string, ParamParser_Generic>> = {
+  [K in keyof P]: P[K] extends Param_GetSet<infer TIn, infer TOut>
+    ? unknown extends TOut // if any or unknown, use the value of TIn, which defaults to string | string[]
+      ? TIn
+      : TOut
+    : never
+}
+
+export class MatcherPatternPathDynamic<
+  TParams extends MatcherParamsFormatted = MatcherParamsFormatted
+> implements MatcherPatternPath<TParams>
+{
+  private params: Record<string, Required<ParamParser_Generic>> = {}
+  constructor(
+    private re: RegExp,
+    params: Record<keyof TParams, ParamParser_Generic>,
+    public build: (params: TParams) => string,
+    private opts: { repeat?: boolean; optional?: boolean } = {}
+  ) {
+    for (const paramName in params) {
+      const param = params[paramName]
+      this.params[paramName] = {
+        get: param.get || PATH_PARAM_DEFAULT_GET,
+        // @ts-expect-error FIXME: should work
+        set: param.set || PATH_PARAM_DEFAULT_SET,
+      }
+    }
+  }
+
+  /**
+   * Match path against the pattern and return
+   *
+   * @param path - path to match
+   * @throws if the patch doesn't match
+   * @returns matched decoded params
+   */
+  match(path: string): TParams {
+    const match = path.match(this.re)
+    if (!match) {
+      throw miss()
+    }
+    let i = 1 // index in match array
+    const params = {} as TParams
+    for (const paramName in this.params) {
+      const currentParam = this.params[paramName]
+      const currentMatch = match[i++]
+      let value: string | null | string[] =
+        this.opts.optional && currentMatch == null ? null : currentMatch
+      value = this.opts.repeat && value ? value.split('/') : value
+
+      params[paramName as keyof typeof params] = currentParam.get(
+        // @ts-expect-error: FIXME: the type of currentParam['get'] is wrong
+        value && (Array.isArray(value) ? value.map(decode) : decode(value))
+      ) as (typeof params)[keyof typeof params]
+    }
+
+    if (__DEV__ && i !== match.length) {
+      console.warn(
+        `Regexp matched ${match.length} params, but ${i} params are defined`
+      )
+    }
+    return params
+  }
+
+  // build(params: TParams): string {
+  //   let path = this.re.source
+  //   for (const param of this.params) {
+  //     const value = params[param.name as keyof TParams]
+  //     if (value == null) {
+  //       throw new Error(`Matcher build: missing param ${param.name}`)
+  //     }
+  //     path = path.replace(
+  //       /([^\\]|^)\([^?]*\)/,
+  //       `$1${encodeParam(param.set(value))}`
+  //     )
+  //   }
+  //   return path
+  // }
+}
+
 export interface MatcherPatternQuery<
   TParams extends MatcherParamsFormatted = MatcherParamsFormatted
 > extends MatcherPatternParams_Base<MatcherQueryParams, TParams> {}