feat: update readme to doc online mode

README.md

@@ -14,22 +14,79 @@
 
 ## Usage
 
+### Modes:
+
+1. Offline: Computes PoW over given CAPTCHA parameters
+2. Online: CLI alternative for people using browsers without JavaScript
+   support
+
 ```bash
-mCaptcha PoW CLI 0.1.0
-Aravinth Manivannan <realaravinth@batsense.net>
-Generates PoW for mCaptcha
+CLI tool to solve mCaptcha
 
-USAGE:
-    mcaptcha-cli [OPTIONS]
+Usage: mcaptcha-cli <COMMAND>
 
-FLAGS:
-    -h, --help       Prints help information
-    -V, --version    Prints version information
+Commands:
+  offline  Compute PoW with offline parameters
+  online   Compute PoW by fetching parameters from  CAPTCHA URL
+  help     Print this message or the help of the given subcommand(s)
 
-OPTIONS:
-    -d, --difficulty <INTEGER>    Difficulty factor
-    -p, --phrase <STRING>         Phrase over which PoW should be computed
-    -s, --salt <STRING>           Salt with which PoW should be computed
+Options:
+  -h, --help     Print help
+  -V, --version  Print version
+```
+
+#### Offline
+
+Help menu:
+
+```bash
+Compute PoW with offline parameters
+
+Usage: mcaptcha-cli offline --salt <SALT> --phrase <PHRASE> --difficulty-factor <DIFFICULTY_FACTOR>
+
+Options:
+  -s, --salt <SALT>                            Salt with which PoW should be computed
+  -p, --phrase <PHRASE>                        Phrase over which PoW should be computed
+  -d, --difficulty-factor <DIFFICULTY_FACTOR>  Difficulty Factor
+  -h, --help                                   Print help
+```
+
+Example usage:
+
+```bash
+13:28 atm@lab cli ±|online|→ mcaptcha-cli offline -s $(rand 32) -p $(rand 32) -d 50000
+difficulty: 50000
+nonce: 90507
+original phrase: f351f333d44b2c6b5bf7f033b065bbb8fb5e9dd153bd402e43ed04425f5a3859
+result: 340276562956196291522979356090220150471
+```
+
+(where rand is
+[this](https://github.com/realaravinth/dotfiles/blob/6fc6c87cc912e17488a35c0d3327ecf393221270/scripts/rand#L20)
+script)
+
+#### Online
+
+Fetches CAPTCHA parameters from CAPTCHA URL, computes PoW, validates
+against given mCaptcha server and returns authorization token
+
+Help menu:
+
+```bash
+Compute PoW by fetching parameters from  CAPTCHA URL
+
+Usage: mcaptcha-cli online --url <URL>
+
+Options:
+  -u, --url <URL>  URL of the CAPTCHA. Example:  https://example.org/widget?sitekey=foo
+  -h, --help       Print help
+```
+
+Example usage:
+
+```bash
+13:32 atm@lab cli ±|online ✗|→ mcaptcha-cli online -u https://demo.mcaptcha.org/widget?sitekey=pHy0AktWyOKuxZDzFfoaewncWecCHo23
+Authorization token: 3xleN26OctBuVu3X4t6CYyUjErhaxQvz
 ```
 
 ## Funding