From abbf16b4bdc6438c80c85f6f092cb61528ef2ced Mon Sep 17 00:00:00 2001
From: NatureFreshMilk <naturefreshmilk@github.com>
Date: Thu, 17 Jan 2019 10:23:48 +0100
Subject: [PATCH] layer parsing

---
 layerconfig/layerconfig.go       | 47 ++++++++++++++++++++++++++++++++
 layerconfig/layerconfig_test.go  | 26 ++++++++++++++++++
 layerconfig/testdata/layers.json |  8 ++++++
 3 files changed, 81 insertions(+)
 create mode 100644 layerconfig/layerconfig.go
 create mode 100644 layerconfig/layerconfig_test.go
 create mode 100644 layerconfig/testdata/layers.json

diff --git a/layerconfig/layerconfig.go b/layerconfig/layerconfig.go
new file mode 100644
index 0000000..7cecf3b
--- /dev/null
+++ b/layerconfig/layerconfig.go
@@ -0,0 +1,47 @@
+package layerconfig
+
+import (
+  "encoding/json"
+  "io/ioutil"
+)
+
+type LayerContainer struct {
+  Layers []Layer `json:"layers"`
+}
+
+type Layer struct {
+  Id int        `json:"id"`
+  Name string  `json:"name"`
+  To int        `json:"to"`
+  From int  `json:"from"`
+}
+
+var DefaultLayers []Layer
+
+func init(){
+  DefaultLayers = []Layer{
+    Layer{
+      Id: 0,
+      Name: "Base",
+      From: -16,
+      To: 160,
+    },
+  }
+}
+
+func ParseFile(filename string) ([]Layer, error) {
+
+  data, err := ioutil.ReadFile(filename)
+  if err != nil {
+    return nil, err
+  }
+
+  lc := LayerContainer{}
+
+  err = json.Unmarshal(data, &lc)
+  if err != nil {
+    return nil, err
+  }
+
+  return lc.Layers, nil
+}
diff --git a/layerconfig/layerconfig_test.go b/layerconfig/layerconfig_test.go
new file mode 100644
index 0000000..4e8cb5d
--- /dev/null
+++ b/layerconfig/layerconfig_test.go
@@ -0,0 +1,26 @@
+package layerconfig
+
+import (
+  "testing"
+)
+
+func TestReadJson(t *testing.T){
+  layers, err := ParseFile("./testdata/layers.json")
+
+  if err != nil {
+    t.Fatal(err)
+  }
+
+  if layers == nil {
+    t.Fatal("no data")
+  }
+
+  if len(layers) != 1 {
+    t.Fatal("length mismatch")
+  }
+
+  if layers[0].Name != "Base" {
+    t.Fatal("name mismatch")
+  }
+
+}
diff --git a/layerconfig/testdata/layers.json b/layerconfig/testdata/layers.json
new file mode 100644
index 0000000..8e405ff
--- /dev/null
+++ b/layerconfig/testdata/layers.json
@@ -0,0 +1,8 @@
+{
+  "layers": [{
+    "id": 0,
+    "name": "Base",
+    "from": -16,
+    "to": 160
+  }]
+}
\ No newline at end of file