feat: add convert command

cli/src/main/kotlin/io/redgreen/tumbleweed/cli/Main.kt

@@ -1,5 +1,6 @@
 package io.redgreen.tumbleweed.cli
 
+import io.redgreen.tumbleweed.cli.dev.convert.ConvertCommand
 import io.redgreen.tumbleweed.cli.dev.json.JsonCommand
 import io.redgreen.tumbleweed.cli.dev.view.ViewCommand
 import io.redgreen.tumbleweed.cli.watch.WatchCommand
@@ -15,11 +16,13 @@ const val DEFAULT_PORT = 7070
     WatchCommand::class,
     JsonCommand::class,
     ViewCommand::class,
+    ConvertCommand::class,
   ],
 )
 class TumbleweedCommand
 
 fun main(args: Array<String>) {
-  exitProcess(CommandLine(TumbleweedCommand())
-    .execute(*args))
+  val status = CommandLine(TumbleweedCommand())
+    .execute(*args)
+  exitProcess(status)
 }

cli/src/main/kotlin/io/redgreen/tumbleweed/cli/dev/convert/ConvertCommand.kt

@@ -0,0 +1,24 @@
+package io.redgreen.tumbleweed.cli.dev.convert
+
+import io.redgreen.tumbleweed.web.observablehq.BilevelEdgeBundlingGraph
+import java.io.File
+import picocli.CommandLine.Command
+import picocli.CommandLine.Parameters
+
+@Command(
+  name = "convert",
+  description = ["(dev) converts a CSV file to an ObservableHQ JSON file"],
+)
+class ConvertCommand : Runnable {
+  @Parameters(
+    index = "0",
+    description = ["path to the CSV file to convert"],
+    arity = "1",
+  )
+  lateinit var csvFile: File
+
+  override fun run() {
+    val graph = BilevelEdgeBundlingGraph.from(csvFile.readText())
+    println(graph.asJson())
+  }
+}

cli/src/main/kotlin/io/redgreen/tumbleweed/cli/dev/json/JsonCommand.kt

@@ -43,7 +43,7 @@ class JsonCommand : Runnable {
     if (check) {
       classStructure.check()
     } else {
-      println(classStructure.graph.json)
+      println(classStructure.graph.asJson())
     }
   }
 }

web-server/src/main/kotlin/io/redgreen/tumbleweed/web/TumbleweedServer.kt

@@ -84,7 +84,7 @@ class TumbleweedServer {
     source: Source,
   ) {
     logger.info("Web socket connection opened. Ready to send updates.")
-    send(Frame.Text(source.graph.json))
+    send(Frame.Text(source.graph.asJson()))
 
     while (true) {
       val message = withContext(Dispatchers.IO) {
@@ -104,7 +104,7 @@ class TumbleweedServer {
       if (!location.exists()) {
         logger.error("Source file does not exist: {}", location)
       } else {
-        structureUpdatesQueue.add(source.graph.json)
+        structureUpdatesQueue.add(source.graph.asJson())
       }
     }
   }

web-server/src/main/kotlin/io/redgreen/tumbleweed/web/observablehq/BilevelEdgeBundlingGraph.kt

@@ -8,12 +8,11 @@ data class BilevelEdgeBundlingGraph(
 ) {
   companion object
 
-  val json: String
-    get() {
-      return jacksonObjectMapper()
-        .writerWithDefaultPrettyPrinter()
-        .writeValueAsString(this)
-    }
+  fun asJson(): String {
+    return jacksonObjectMapper()
+      .writerWithDefaultPrettyPrinter()
+      .writeValueAsString(this)
+  }
 
   data class Node(
     val id: String,