a lot: profiles, some more help strings. partial: exceptions instead of exit()

Signed-off-by: InsanePrawn <insane.prawny@gmail.com>

boot.py

@@ -2,13 +2,20 @@ import os
 import urllib.request
 from image import get_device_and_flavour, get_image_name, dump_bootimg, dump_lk2nd
 from fastboot import fastboot_boot, fastboot_erase_dtbo
-from constants import BOOT_STRATEGIES, FASTBOOT, JUMPDRIVE, LK2ND, JUMPDRIVE_VERSION
+from constants import BOOT_STRATEGIES, FLASH_PARTS, FASTBOOT, JUMPDRIVE, JUMPDRIVE_VERSION
 import click
+import logging
+
+LK2ND = FLASH_PARTS['LK2ND']
+BOOTIMG = FLASH_PARTS['BOOTIMG']
+
+TYPES = [LK2ND, JUMPDRIVE, BOOTIMG]
 
 
 @click.command(name='boot')
-@click.argument('type', required=False)
+@click.argument('type', required=False, default=BOOTIMG)
 def cmd_boot(type):
+    f"""Flash one of {', '.join(TYPES)}"""
     device, flavour = get_device_and_flavour()
     image_name = get_image_name(device, flavour)
     strategy = BOOT_STRATEGIES[device]
@@ -21,8 +28,9 @@ def cmd_boot(type):
                 urllib.request.urlretrieve(f'https://github.com/dreemurrs-embedded/Jumpdrive/releases/download/{JUMPDRIVE_VERSION}/{file}', path)
         elif type == LK2ND:
             path = dump_lk2nd(image_name)
-        else:
+        elif type == BOOTIMG:
             path = dump_bootimg(image_name)
-
+        else:
+            raise Exception(f'Unknown boot image type {type}')
         fastboot_erase_dtbo()
         fastboot_boot(path)