commit 9d6ed7453df231d13b8706e06e76cd743ade6cbc
Author: Niten <niten@fudo.org>
Date:   Sat Jul 9 10:51:47 2022 -0700

    Initial checkin

diff --git a/deps.edn b/deps.edn
new file mode 100644
index 0000000..35337f2
--- /dev/null
+++ b/deps.edn
@@ -0,0 +1,27 @@
+{
+ :paths ["src"]
+
+ :deps {
+        org.clojure/clojure    { :mvn/version "1.11.1" }
+        org.clojure/core.async { :mvn/version "1.5.648" }
+        }
+ :aliases {
+           :test {
+                  :extra-paths ["test"]
+                  :extra-deps {
+                               io.github.cognitect-labs/test-runner
+                               {
+                                :git/url "https://github.com/cognitect-labs/test-runner.git"
+                                :sha "dfb30dd6605cb6c0efc275e1df1736f6e90d4d73"
+                                }
+                               }
+                  :main-opts ["-m" "cognitect.test-runner"]
+                  :exec-fn cognitect.test-runner.api/test
+                  }
+
+           :lint {
+                  :replace-deps { clj-kondo/clj-kondo {:mvn/version "2022.04.25"} }
+                  :main-opts ["-m" "clj-kondo.main" "--lint" "src"]
+                  }
+           }
+ }
diff --git a/src/firmament/connection.clj b/src/firmament/connection.clj
new file mode 100644
index 0000000..8cc7e18
--- /dev/null
+++ b/src/firmament/connection.clj
@@ -0,0 +1,24 @@
+(ns firmament.connection
+  (:require [clojure.edn :as edn])
+  (:import java.security.MessageDigest))
+
+(defprotocol IFirmConnection
+  (read!   [self id])
+  (write!  [self data]))
+
+(defn- sha256 [string]
+  (let [digest (.digest (MessageDigest/getInstance "SHA-256")
+                        (.getBytes string "UTF-8"))]
+    (apply str (map (partial format "%02x") digest))))
+
+(defn firmament-cache []
+  (let [store (atom {})]
+    (reify IFirmConnection
+      (read!  [_ id]
+        (some-> (get @store id)
+                (edn/read-string)))
+      (write! [_ data]
+        (let [data-str (-> data prn-str)
+              id (sha256 data-str)]
+          (swap! store assoc id data-str)
+          id)))))
diff --git a/src/firmament/core.clj b/src/firmament/core.clj
new file mode 100644
index 0000000..9352746
--- /dev/null
+++ b/src/firmament/core.clj
@@ -0,0 +1,26 @@
+(ns firmament.core
+  (:require [clojure.string :as str]))
+
+;; Namespaces and code files
+
+;; Dependencies specify namespaces, and the same rules as clojure apply
+
+
+(defprotocol IFirmFilesystem
+  (read [self filename])
+  (write [self filename content])
+  (entries [self dirname]))
+
+(defn make-filesystem
+  ([conn] (make-filesystem [conn nil]))
+  ([conn original-root]
+   (let [root (atom original-root)]
+     (reify IFirmFilesystem
+       (read [_ path]
+         (read-file conn @root path))
+       (write [_ path content]
+         (swap! root
+                (fn [old-root]
+                  (write-path conn old-root path content))))
+       (entries [_ dirname]
+         (list-entries conn @root dirname))))))
diff --git a/src/firmament/directory.clj b/src/firmament/directory.clj
new file mode 100644
index 0000000..75d9d55
--- /dev/null
+++ b/src/firmament/directory.clj
@@ -0,0 +1,36 @@
+(ns firmament.directory
+  (:require [firmament.directory :as dir]
+            [firmament.type :as t]
+            [clojure.spec.alpha :as s]))
+
+(s/def ::entries (s/map-of keyword? ::t/firmament-id))
+
+(defn create [& entries]
+  {::t/type ::t/directory
+   ::entries (apply hash-map entries)})
+
+(defn entry-id [dir entry]
+  (get-in dir [::entries entry]))
+
+#_(defn- load-entry! [conn dir entry]
+  (conn/read! conn (get-entry-id dir entry)))
+
+#_(defn- read-or-create! [conn id]
+  (if-let [dir (conn/read! conn id)]
+    dir
+    (create)))
+
+#_(defn load! [conn dir entry]
+  (dir/read-or-create! conn (get-entry-id dir entry)))
+
+#_(defn add-entry! [conn dir entry data]
+    (assoc-in dir [::entries entry] (conn/write conn data)))
+
+(defn entries [dir]
+  (::entries dir))
+
+(defn add-entry [dir entry id]
+  (assoc-in dir [::entries entry] id))
+
+(defn directory? [o]
+  (and (map? o) (= ::t/directory (::t/type o))))
diff --git a/src/firmament/filesystem.clj b/src/firmament/filesystem.clj
new file mode 100644
index 0000000..f5cd327
--- /dev/null
+++ b/src/firmament/filesystem.clj
@@ -0,0 +1,21 @@
+(ns firmament.filesystem
+  (:require [firmament.path :as path]))
+
+(defprotocol IFirmFilesystem
+  (read! [self filename])
+  (write! [self filename content])
+  (entries! [self dirname]))
+
+(defn make-filesystem
+  ([conn] (make-filesystem conn nil))
+  ([conn original-root]
+   (let [root (atom original-root)]
+     (reify IFirmFilesystem
+       (read! [_ path]
+         (path/read-file! conn @root path))
+       (write! [_ path content]
+         (swap! root
+                (fn [old-root]
+                  (path/write! conn old-root path content))))
+       (entries! [_ dirname]
+         (path/list-entries! conn @root dirname))))))
diff --git a/src/firmament/object.clj b/src/firmament/object.clj
new file mode 100644
index 0000000..c53ea0c
--- /dev/null
+++ b/src/firmament/object.clj
@@ -0,0 +1,8 @@
+(ns firmament.object
+  (:require [firmament.type :as t]))
+
+(defn create [data]
+  {::t/type ::t/object ::t/data data})
+
+(defn data [obj]
+  (::t/data obj))
diff --git a/src/firmament/path.clj b/src/firmament/path.clj
new file mode 100644
index 0000000..3bfcf8c
--- /dev/null
+++ b/src/firmament/path.clj
@@ -0,0 +1,49 @@
+(ns firmament.path
+  (:require [clojure.string :as str]
+            [firmament.directory :as dir]
+            [firmament.object :as object]
+            [firmament.connection :as conn]))
+
+(defn- path-elements [path]
+  (str/split path #"/"))
+
+(defn- read! [conn root path]
+  (loop [curr      (conn/read! conn root)
+         remaining (path-elements path)]
+    (when (nil? curr)
+      (throw (ex-info (str "path does not exist: " path)
+                      {:root root})))
+    (if (not (seq remaining))
+      curr
+      (recur (conn/read! conn (dir/entry-id curr (first remaining)))
+             (rest remaining)))))
+
+(defn read-file! [conn root path]
+  (some-> (read! conn root path) (object/data)))
+
+(defn list-entries! [conn root path]
+  (some-> (read! conn root path) (dir/entries) (keys)))
+
+(defn save-entry! [conn dir entry data]
+  (dir/add-entry dir entry (conn/write! conn data)))
+
+(defn load-dir-entry! [conn base entry]
+  (if-let [dir (conn/read! conn (dir/entry-id base entry))]
+    dir
+    (dir/create)))
+
+(defn- write-internal [conn curr [el & els] obj]
+  (if (seq els)
+    (save-entry! conn curr el
+                 (write-internal conn
+                                 (load-dir-entry! conn curr el)
+                                 els
+                                 obj))
+    (save-entry! conn curr el obj)))
+
+(defn write! [conn root path data]
+  (conn/write! conn
+               (write-internal conn
+                               (conn/read! conn root)
+                               (path-elements path)
+                               (object/create data))))
diff --git a/src/firmament/type.clj b/src/firmament/type.clj
new file mode 100644
index 0000000..741cb1d
--- /dev/null
+++ b/src/firmament/type.clj
@@ -0,0 +1,12 @@
+(ns firmament.type
+  (:require [clojure.spec.alpha :as s]))
+
+(def firmament-id? string?)
+
+(s/def ::firmament-id firmament-id?)
+
+(def firmament-data? string?)
+
+(s/def ::type #{::directory ::object})
+
+(s/def ::data firmament-data?)