docs: add mnemonic.md

Author: recanman

docs/Mnemonic.md

@@ -0,0 +1,247 @@
+## Mnemonic Class
+
+### Namespace
+
+```php
+namespace MoneroIntegrations\MoneroCrypto;
+```
+
+### Class: Mnemonic
+
+The `Mnemonic` class provides methods for encoding, decoding, validating checksums, and managing wordsets for Monero wallets.
+
+#### Method: `checksum`
+
+Given a mnemonic seed word list, return the seed checksum.
+
+```php
+/**
+ * Given a mnemonic seed word list, return the seed checksum.
+ *
+ * @param array<string> $words
+ * @param int $prefix_len
+ * @return string
+ */
+public static function checksum(array $words, int $prefix_len): string
+```
+
+##### Example:
+
+```php
+$seed = [
+    "sighting", "pavements", "mocked", "dilute", 
+    "lunar", "king", "bygones", "niece", "tonic", 
+    "noises", "ostrich", "ecstatic", "hoax", "gawk", 
+    "bays", "wiring", "total", "emulate", "update", 
+    "bypass", "asked", "pager", "geometry", "haystack", 
+    "geometry"
+];
+$prefixLen = 3;
+$checksum = Mnemonic::checksum($seed, $prefixLen); // Returns "geometry"
+```
+
+#### Method: `validateChecksum`
+
+Given a mnemonic seed word list, check if checksum word is valid.
+
+```php
+/**
+ * Given a mnemonic seed word list, check if checksum word is valid.
+ *
+ * @param array<string> $words
+ * @param int $prefix_len
+ * @return bool
+ */
+public static function validateChecksum(array $words, int $prefix_len): bool
+```
+
+Example:
+
+```php
+$isValid = Mnemonic::validateChecksum($seed, $prefixLen); // Returns true
+```
+
+#### Method: `swapEndian`
+
+Given an 8 byte word (or shorter), pads to 8 bytes (adds 0 at left) and reverses endian byte order.
+
+```php
+/**
+ * Given an 8 byte word (or shorter), pads to 8 bytes (adds 0 at left) and reverses endian byte order.
+ *
+ * @param string $word
+ * @return string
+ */
+public static function swapEndian(string $word): string
+```
+
+Example:
+
+```php
+$word = "12345678";
+$swapped = Mnemonic::swapEndian($word); // Returns "78563412"
+```
+
+#### Method: `encode`
+
+Given a hexadecimal key string (seed), return its mnemonic representation.
+
+```php
+/**
+ * Given a hexadecimal key string (seed), return its mnemonic representation.
+ *
+ * @param string $seed
+ * @param string|null $wordset_name
+ * @return array<string>
+ */
+public static function encode(string $seed, ?string $wordset_name = null): array
+```
+
+Example:
+
+```php
+$seedHex = "f2750ee6e1f326f485fdc34ac517a69cbd9c72c5766151626039f0eeab40e109";
+$encodedMnemonic = Mnemonic::encode($seedHex, "english"); // Returns an array of mnemonic words
+```
+
+#### Method: `encodeWithChecksum`
+
+Given a hexadecimal key string (seed), return its mnemonic representation plus an extra checksum word.
+
+```php
+/**
+ * Given a hexadecimal key string (seed), return its mnemonic representation plus an extra checksum word.
+ *
+ * @param string $seed
+ * @param string|null $wordset_name
+ * @return array<string>
+ */
+public static function encodeWithChecksum(string $seed, ?string $wordset_name = null): array
+```
+
+Example:
+
+```php
+$seedHex = "f2750ee6e1f326f485fdc34ac517a69cbd9c72c5766151626039f0eeab40e109";
+$mnemonicWithChecksum = Mnemonic::encodeWithChecksum($seedHex, "english"); // Returns an array of mnemonic words with checksum
+```
+
+#### Method: `decode`
+
+Given a mnemonic word list, return a hexadecimal encoded string (seed).
+
+```php
+/**
+ * Given a mnemonic word list, return a hexadecimal encoded string (seed).
+ *
+ * @param array<string> $wlist
+ * @param string|null $wordset_name
+ * @return string
+ * @throws Exception if decoding fails.
+ */
+public static function decode(array $wlist, ?string $wordset_name = null): string
+```
+
+Example:
+
+```php
+$mnemonicWords = ["sighting", "pavements", "mocked", ...];
+$decodedSeedHex = Mnemonic::decode($mnemonicWords, "english"); // Returns the hexadecimal seed string
+```
+
+#### Method: `getWordsetByName`
+
+Given a wordset identifier, returns the full wordset.
+
+```php
+/**
+ * Given a wordset identifier, returns the full wordset.
+ *
+ * @param string|null $name
+ * @return array<string>
+ * @throws Exception if the wordset name is invalid.
+ */
+public static function getWordsetByName(?string $name = null): array
+```
+
+Example:
+
+```php
+$wordsetDetails = Mnemonic::getWordsetByName("english"); // Returns details of the English wordset
+```
+
+#### Method: `findWordsetByMnemonic`
+
+Given a mnemonic array of words, returns the name of the matching wordset.
+
+```php
+/**
+ * Given a mnemonic array of words, returns the name of the matching wordset.
+ *
+ * @param array<string> $mnemonic
+ * @return string|null
+ * @throws Exception if more than one wordset matches the mnemonic.
+ */
+public static function findWordsetByMnemonic(array $mnemonic): ?string
+```
+
+Example:
+
+```php
+$matchedWordset = Mnemonic::findWordsetByMnemonic($mnemonicWords); // Returns "english" if the mnemonic matches
+```
+
+#### Method: `getWordsetList`
+
+Return a list of available wordset names.
+
+```php
+/**
+ * Return a list of available wordset names.
+ *
+ * @return array<string>
+ */
+public static function getWordsetList(): array
+```
+
+Example:
+
+```php
+$wordsetList = Mnemonic::getWordsetList(); // Returns an array of available wordset names
+```
+
+#### Method: `getWordsets`
+
+Return a list of available wordsets with details.
+
+```php
+/**
+ * Return a list of available wordsets with details.
+ *
+ * @return array<string, array<string, string|int|array<string>>>
+ */
+public static function getWordsets(): array
+```
+
+Example:
+
+```php
+$allWordsets = Mnemonic::getWordsets(); // Returns an array of all available wordsets with details
+```
+
+### Interfaces
+
+#### Interface: `Wordset`
+
+The `Wordset` interface is implemented by classes representing different wordsets.
+
+```php
+interface Wordset {
+    public static function name(): string;
+    public static function englishName(): string;
+    public static function prefixLength(): int;
+    public static function words(): array;
+}
+```
+
+This interface defines methods that must be implemented by each wordset class. It provides information about the name, English name, prefix length, and word list of a wordset.