For APKPure, allow specifying more options e.g. arch= and add usage file.

Author: Hainish

README.md

@@ -47,8 +47,11 @@ The simplest example is to download a single APK to the current directory:
 apkeep -a com.instagram.android .
 ```
 
-This downloads from the default source, APKPure, which does not require credentials.  To
-download directly from the google play store, you will first have to [obtain an AAS token](USAGE-google-play.md).
+This downloads from the default source, APKPure, which does not require credentials. For more
+APKPure usage examples, such as specifying a package architecture, refer to the
+[`USAGE-apkpure.md`](USAGE-apkpure.md) document.
+
+To download directly from the google play store, you will first have to [obtain an AAS token](USAGE-google-play.md).
 Then,
 
 ```shell

USAGE-apkpure.md

@@ -0,0 +1,36 @@
+APKPure is the default download source. To download from APKPure:
+
+```shell
+apkeep -a com.instagram.android .
+```
+
+Or, if you wish to explicitly specify the download source:
+
+```shell
+apkeep -a com.instagram.android -d apk-pure .
+```
+
+More advanced options for this download source can be passed with the `-o` option. For instance, download a specific architecture variant of an app with `arch=`:
+
+```shell
+apkeep -a com.instagram.android -o 'arch=x86' .
+```
+
+To specify multiple architectures, separate the `arch=` specification with a semicolon. The following shows the default `arch` option:
+
+```shell
+apkeep -a com.instagram.android -o 'arch=arm64-v8a;armeabi-v7a;armeabi;x86;x86_64' .
+```
+
+You can also list the versions available, either specifying a specific architecture or not:
+
+```shell
+apkeep -l -a com.instagram.android -o 'arch=x86'
+apkeep -l -a com.instagram.android
+```
+
+To specify a preferred language or Android API version, use the `language=` or `os_ver` options. The following shows the defaults:
+
+```shell
+apkeep -a com.instagram.android -o 'language=en-US,os_ver=35' .
+```

src/consts.rs

@@ -1,5 +1,4 @@
-pub const APKPURE_VERSIONS_URL_FORMAT: &str = "https://api.pureapk.com/m/v3/cms/app_version?hl=en-US&package_name=";
-pub const APKPURE_DOWNLOAD_URL_REGEX: &str = r"(X?APKJ)..(https?://(www\.)?[-a-zA-Z0-9@:%._\+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_\+.~#?&//=]*))";
+pub const APKPURE_VERSIONS_URL_FORMAT: &str = "https://tapi.pureapk.com/v3/get_app_his_version?hl=en&package_name=";
 pub const FDROID_REPO: &str = "https://f-droid.org/repo";
 pub const FDROID_INDEX_FINGERPRINT: &[u8] = &[67, 35, 141, 81, 44, 30, 94, 178, 214, 86, 159, 74, 58, 251, 245, 82, 52, 24, 184, 46, 10, 62, 209, 85, 39, 112, 171, 185, 169, 201, 204, 171];
 pub const FDROID_SIGNATURE_BLOCK_FILE_REGEX: &str = r"^META-INF/.*\.(DSA|EC|RSA)$";