refactor(stash)!: extract implementation of api

lib/src/stash.dart

@@ -1,4 +1,5 @@
 import 'package:libgit2dart/libgit2dart.dart';
+import 'bindings/stash.dart' as bindings;
 
 class Stash {
   /// Initializes a new instance of [Stash] class.
@@ -17,6 +18,92 @@ class Stash {
   /// The commit oid of the stashed state.
   final Oid oid;
 
+  /// Returns list of all the stashed states, first being the most recent.
+  static List<Stash> list(Repository repo) => bindings.list(repo.pointer);
+
+  /// Saves the local modifications to a new stash.
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  static Oid create({
+    required Repository repo,
+    required Signature stasher,
+    String? message,
+    bool keepIndex = false,
+    bool includeUntracked = false,
+    bool includeIgnored = false,
+  }) {
+    int flags = 0;
+    if (keepIndex) flags |= GitStash.keepIndex.value;
+    if (includeUntracked) flags |= GitStash.includeUntracked.value;
+    if (includeIgnored) flags |= GitStash.includeIgnored.value;
+
+    return Oid(bindings.save(
+      repoPointer: repo.pointer,
+      stasherPointer: stasher.pointer,
+      message: message,
+      flags: flags,
+    ));
+  }
+
+  /// Applies a single stashed state from the stash list.
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  static void apply({
+    required Repository repo,
+    int index = 0,
+    bool reinstateIndex = false,
+    Set<GitCheckout> strategy = const {
+      GitCheckout.safe,
+      GitCheckout.recreateMissing
+    },
+    String? directory,
+    List<String>? paths,
+  }) {
+    bindings.apply(
+      repoPointer: repo.pointer,
+      index: index,
+      flags: reinstateIndex ? GitStashApply.reinstateIndex.value : 0,
+      strategy: strategy.fold(0, (acc, e) => acc | e.value),
+      directory: directory,
+      paths: paths,
+    );
+  }
+
+  /// Removes a single stashed state from the stash list.
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  static void drop({required Repository repo, int index = 0}) {
+    bindings.drop(
+      repoPointer: repo.pointer,
+      index: index,
+    );
+  }
+
+  /// Applies a single stashed state from the stash list and remove it from
+  /// the list if successful.
+  ///
+  /// Throws a [LibGit2Error] if error occured.
+  static void pop({
+    required Repository repo,
+    int index = 0,
+    bool reinstateIndex = false,
+    Set<GitCheckout> strategy = const {
+      GitCheckout.safe,
+      GitCheckout.recreateMissing
+    },
+    String? directory,
+    List<String>? paths,
+  }) {
+    bindings.pop(
+      repoPointer: repo.pointer,
+      index: index,
+      flags: reinstateIndex ? GitStashApply.reinstateIndex.value : 0,
+      strategy: strategy.fold(0, (acc, e) => acc | e.value),
+      directory: directory,
+      paths: paths,
+    );
+  }
+
   @override
   String toString() {
     return 'Stash{index: $index, message: $message, sha: ${oid.sha}}';