Refactor input parameters

Moved reading of all input parameters into a common source: `input-params.ts`.
This centralized all input parameter reads, and allowed an improved implementation
of reading boolean parameters. In particular, the implementation now provides a default
value for a boolean input parameter that isn't declared for an action.

src/input-params.ts

@@ -0,0 +1,77 @@
+import * as core from '@actions/core'
+import {parseArgsStringToArgv} from 'string-argv'
+
+export function isCacheDisabled(): boolean {
+    return getBooleanInput('cache-disabled')
+}
+
+export function isCacheReadOnly(): boolean {
+    return getBooleanInput('cache-read-only')
+}
+
+export function isCacheWriteOnly(): boolean {
+    return getBooleanInput('cache-write-only')
+}
+
+export function isCacheStrictMatch(): boolean {
+    return getBooleanInput('gradle-home-cache-strict-match')
+}
+
+export function isCacheDebuggingEnabled(): boolean {
+    return process.env['GRADLE_BUILD_ACTION_CACHE_DEBUG_ENABLED'] ? true : false
+}
+
+export function isCacheCleanupEnabled(): boolean {
+    return getBooleanInput('gradle-home-cache-cleanup')
+}
+
+export function getCacheIncludes(): string[] {
+    return core.getMultilineInput('gradle-home-cache-includes')
+}
+
+export function getCacheExcludes(): string[] {
+    return core.getMultilineInput('gradle-home-cache-excludes')
+}
+
+export function getBuildRootDirectory(): string {
+    return core.getInput('build-root-directory')
+}
+
+export function getGradleVersion(): string {
+    return core.getInput('gradle-version')
+}
+
+export function getGradleExecutable(): string {
+    return core.getInput('gradle-executable')
+}
+
+export function getArguments(): string[] {
+    const input = core.getInput('arguments')
+    return parseArgsStringToArgv(input)
+}
+
+// Internal parameters
+export function getJobContext(): string {
+    return core.getInput('workflow-job-context')
+}
+
+export function getGithubToken(): string {
+    return core.getInput('github-token', {required: true})
+}
+
+export function isJobSummaryEnabled(): boolean {
+    return getBooleanInput('generate-job-summary', true)
+}
+
+function getBooleanInput(paramName: string, paramDefault = false): boolean {
+    const paramValue = core.getInput(paramName)
+    switch (paramValue.toLowerCase().trim()) {
+        case '':
+            return paramDefault
+        case 'false':
+            return false
+        case 'true':
+            return true
+    }
+    throw TypeError(`The value '${paramValue} is not valid for '${paramName}. Valid values are: [true, false]`)
+}