1 files changed, 97 insertions, 0 deletions
diff --git a/internal/options/options.go b/internal/options/options.go
new file mode 100644
index 0000000..3e253c5
--- /dev/null
+++ b/internal/options/options.go
@@ -0,0 +1,97 @@
+package options
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	"os"
+
+	"rgdd.se/silent-ct/internal/manager"
+	"rgdd.se/silent-ct/pkg/monitor"
+	"rgdd.se/silent-ct/pkg/server"
+)
+
+const usage = `Usage:
+
+  silent-ct [Options]
+
+Options:
+
+  -h, --help:      Output usage message and exit
+  -c, --config:    Path to a configuration file (Default: %s)
+  -l, --listen:    Listen address to receive submission on (Default: %s)
+  -s, --state:     Path to a directory where state is stored (Default: %s)
+
+Example configuration file:
+
+  {
+    "monitor": [
+      {
+        "wildcard": "example.org",
+        "excludes": [
+          "test"
+        ]
+      }
+    ],
+    "nodes": [
+      {
+        "name": "node_a",
+        "secret": "aaaa",
+        "issues": [
+          "example.org",
+          "www.example.org"
+        ]
+      }
+    ]
+  }
+
+`
+
+// Options are command-line options the user can specify
+type Options struct {
+	ListenAddr string
+	ConfigFile string
+	StateDir   string
+}
+
+func New(cmd string, args []string) (opts Options, err error) {
+	fs := flag.NewFlagSet(cmd, flag.ContinueOnError)
+	fs.Usage = func() {
+		fmt.Fprintf(os.Stderr, usage, server.DefaultConfigFile, server.DefaultAddress, manager.DefaultStateDir)
+	}
+	stringOpt(fs, &opts.ConfigFile, "config", "c", server.DefaultConfigFile)
+	stringOpt(fs, &opts.ListenAddr, "listen", "l", server.DefaultAddress)
+	stringOpt(fs, &opts.StateDir, "state", "s", manager.DefaultStateDir)
+	if err = fs.Parse(args); err != nil {
+		return opts, err
+	}
+
+	if opts.ConfigFile == "" {
+		return opts, fmt.Errorf("-c, --config: must not be an empty string")
+	}
+	if opts.StateDir == "" {
+		return opts, fmt.Errorf("-s, --state: must not be an empty string")
+	}
+	if opts.ListenAddr == "" {
+		return opts, fmt.Errorf("-l, --listen: must not be an empty string")
+	}
+	return opts, err
+}
+
+func stringOpt(fs *flag.FlagSet, opt *string, short, long, value string) {
+	fs.StringVar(opt, short, value, "")
+	fs.StringVar(opt, long, value, "")
+}
+
+type Config struct {
+	Monitor monitor.MatchWildcards `json:"monitor"`
+	Nodes   server.Nodes           `json:"nodes"`
+}
+
+func (c *Config) FromFile(fileName string) error {
+	b, err := os.ReadFile(fileName)
+	if err != nil {
+		return err
+	}
+	return json.Unmarshal(b, c)
+}