Add TSV parser and minimal UI for file selection dialog

app/src/main/java/com/illusionware/npsbrowser/MainActivity.kt

@@ -1,12 +0,0 @@
-package com.illusionware.npsbrowser
-
-import androidx.appcompat.app.AppCompatActivity
-import android.os.Bundle
-
-class MainActivity : AppCompatActivity() {
-
-    override fun onCreate(savedInstanceState: Bundle?) {
-        super.onCreate(savedInstanceState)
-        setContentView(R.layout.activity_main)
-    }
-}

app/src/main/java/com/illusionware/npsbrowser/activities/MainActivity.kt

@@ -0,0 +1,58 @@
+package com.illusionware.npsbrowser.activities
+
+import android.Manifest
+import android.app.Activity
+import android.content.Intent
+import android.content.pm.PackageManager
+import android.os.Bundle
+import android.util.Log
+import androidx.appcompat.app.AppCompatActivity
+import androidx.core.app.ActivityCompat
+import com.github.doyaaaaaken.kotlincsv.dsl.csvReader
+import com.illusionware.npsbrowser.databinding.ActivityMainBinding
+import java.io.InputStream
+
+class MainActivity : AppCompatActivity() {
+
+    private val tsvReader = csvReader {
+        charset = "UTF-8"
+        quoteChar = '"'
+        delimiter = '\t'
+    }
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        val binding = ActivityMainBinding.inflate(layoutInflater);
+        setContentView(binding.root)
+
+        binding.tsvChooserButton.setOnClickListener {
+            if (!isStoragePermissionGranted())
+                return@setOnClickListener
+            val intent = Intent(Intent.ACTION_GET_CONTENT).apply {
+                addCategory(Intent.CATEGORY_OPENABLE)
+                type = "text/tab-separated-values"
+            }
+            startActivityForResult(intent, 1)
+        }
+    }
+    override fun onActivityResult(requestCode: Int, resultCode: Int, resultData: Intent?) {
+        super.onActivityResult(requestCode, resultCode, resultData)
+        if (requestCode == 1 && resultCode == Activity.RESULT_OK) {
+            resultData?.data?.also { uri ->
+                val inputStream: InputStream? = contentResolver.openInputStream(uri)
+                val entries : List<Map<String, String>> = tsvReader.readAllWithHeader(inputStream!!)
+            }
+        }
+    }
+
+    private fun isStoragePermissionGranted(): Boolean {
+        return  if (checkSelfPermission(Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED) {
+                Log.v("perms", "Permission is granted")
+                true
+            } else {
+                Log.v("perms", "Permission is revoked")
+                ActivityCompat.requestPermissions(this, arrayOf(Manifest.permission.READ_EXTERNAL_STORAGE), 1)
+                false
+            }
+    }
+}