enhance console gui for invokeai-merge (#2480)

- Added modest adaptive behavior; if the screen is wide enough the three
checklists of models will be arranged in a horizontal row.
- Added color support
# What it looks like
On a wide window:

![image](https://user-images.githubusercontent.com/111189/216495149-0ceed761-b829-4b21-8e90-0b7faf2c7b72.png)
On a narrow window:

![image](https://user-images.githubusercontent.com/111189/216495239-1d6615cf-0e7e-44fe-83d7-513819635d8a.png)

ldm/invoke/merge_diffusers.py

@@ -5,13 +5,15 @@
 Copyright (c) 2023 Lincoln Stein and the InvokeAI Development Team
 """
 import argparse
+import curses
 import os
 import sys
 from argparse import Namespace
 from pathlib import Path
 from typing import List, Union
 
 import npyscreen
+import warnings
 from diffusers import DiffusionPipeline
 from omegaconf import OmegaConf
 
@@ -26,7 +28,6 @@
 
 DEST_MERGED_MODEL_DIR = "merged_models"
 
-
 def merge_diffusion_models(
     model_ids_or_paths: List[Union[str, Path]],
     alpha: float = 0.5,
@@ -185,6 +186,8 @@ class mergeModelsForm(npyscreen.FormMultiPageAction):
 
     def __init__(self, parentApp, name):
         self.parentApp = parentApp
+        self.ALLOW_RESIZE=True
+        self.FIX_MINIMUM_SIZE_WHEN_CREATED=False
         super().__init__(parentApp, name)
 
     @property
@@ -195,29 +198,94 @@ def afterEditing(self):
         self.parentApp.setNextForm(None)
 
     def create(self):
+        window_height,window_width=curses.initscr().getmaxyx()
+
         self.model_names = self.get_model_names()
-
+        max_width = max([len(x) for x in self.model_names])
+        max_width += 6
+        horizontal_layout = max_width*3 < window_width
+
+        self.add_widget_intelligent(
+            npyscreen.FixedText,
+            color='CONTROL',
+            value=f"Select two models to merge and optionally a third.",
+            editable=False,
+        )
+        self.add_widget_intelligent(
+            npyscreen.FixedText,
+            color='CONTROL',
+            value=f"Use up and down arrows to move, <space> to select an item, <tab> and <shift-tab> to move from one field to the next.",
+            editable=False,
+        )
+        self.add_widget_intelligent(
+            npyscreen.FixedText,
+            value='MODEL 1',
+            color='GOOD',
+            editable=False,
+            rely=4 if horizontal_layout else None,
+        )
+        self.model1 = self.add_widget_intelligent(
+            npyscreen.SelectOne,
+            values=self.model_names,
+            value=0,
+            max_height=len(self.model_names),
+            max_width=max_width,
+            scroll_exit=True,
+            rely=5,
+        )
         self.add_widget_intelligent(
-            npyscreen.FixedText, name="Select up to three models to merge", value=""
+            npyscreen.FixedText,
+            value='MODEL 2',
+            color='GOOD',
+            editable=False,
+            relx=max_width+3 if horizontal_layout else None,
+            rely=4 if horizontal_layout else None,
         )
-        self.models = self.add_widget_intelligent(
-            npyscreen.TitleMultiSelect,
-            name="Select two to three models to merge:",
+        self.model2 = self.add_widget_intelligent(
+            npyscreen.SelectOne,
+            name='(2)',
             values=self.model_names,
-            value=None,
-            max_height=len(self.model_names) + 1,
+            value=1,
+            max_height=len(self.model_names),
+            max_width=max_width,
+            relx=max_width+3 if horizontal_layout else None,
+            rely=5 if horizontal_layout else None,
+            scroll_exit=True,
+        )
+        self.add_widget_intelligent(
+            npyscreen.FixedText,
+            value='MODEL 3',
+            color='GOOD',
+            editable=False,
+            relx=max_width*2+3 if horizontal_layout else None,
+            rely=4 if horizontal_layout else None,
+        )
+        models_plus_none = self.model_names.copy()
+        models_plus_none.insert(0,'None')
+        self.model3 = self.add_widget_intelligent(
+            npyscreen.SelectOne,
+            name='(3)',
+            values=models_plus_none,
+            value=0,
+            max_height=len(self.model_names)+1,
+            max_width=max_width,
             scroll_exit=True,
+            relx=max_width*2+3 if horizontal_layout else None,
+            rely=5 if horizontal_layout else None,
         )
-        self.models.when_value_edited = self.models_changed
+        for m in [self.model1,self.model2,self.model3]:
+            m.when_value_edited = self.models_changed
         self.merged_model_name = self.add_widget_intelligent(
             npyscreen.TitleText,
             name="Name for merged model:",
+            labelColor='CONTROL',
             value="",
             scroll_exit=True,
         )
         self.force = self.add_widget_intelligent(
             npyscreen.Checkbox,
             name="Force merge of incompatible models",
+            labelColor='CONTROL',
             value=False,
             scroll_exit=True,
         )
@@ -226,6 +294,7 @@ def create(self):
             name="Merge Method:",
             values=self.interpolations,
             value=0,
+            labelColor='CONTROL',
             max_height=len(self.interpolations) + 1,
             scroll_exit=True,
         )
@@ -236,47 +305,53 @@ def create(self):
             step=0.05,
             lowest=0,
             value=0.5,
+            labelColor='CONTROL',
             scroll_exit=True,
         )
-        self.models.editing = True
+        self.model1.editing = True
 
     def models_changed(self):
-        model_names = self.models.values
-        selected_models = self.models.value
-        if len(selected_models) > 3:
-            npyscreen.notify_confirm(
-                "Too many models selected for merging. Select two to three."
-            )
-            return
-        elif len(selected_models) > 2:
-            self.merge_method.values = ["add_difference"]
-            self.merge_method.value = 0
+        models = self.model1.values
+        selected_model1 = self.model1.value[0]
+        selected_model2 = self.model2.value[0]
+        selected_model3 = self.model3.value[0]
+        merged_model_name = f'{models[selected_model1]}+{models[selected_model2]}'
+        self.merged_model_name.value = merged_model_name
+
+        if selected_model3 > 0:
+            self.merge_method.values=['add_difference'],
+            self.merged_model_name.value += f'+{models[selected_model3]}'
         else:
-            self.merge_method.values = self.interpolations
-        self.merged_model_name.value = "+".join(
-            [model_names[x] for x in selected_models]
-        )
+            self.merge_method.values=self.interpolations
+        self.merge_method.value=0
 
     def on_ok(self):
         if self.validate_field_values() and self.check_for_overwrite():
             self.parentApp.setNextForm(None)
             self.editing = False
             self.parentApp.merge_arguments = self.marshall_arguments()
-            npyscreen.notify("Starting the merge...")
+            npyscreen.notify('Starting the merge...')
         else:
             self.editing = True
 
     def on_cancel(self):
         sys.exit(0)
 
-    def marshall_arguments(self) -> dict:
-        models = [self.models.values[x] for x in self.models.value]
+    def marshall_arguments(self)->dict:
+        model_names = self.model_names
+        models = [
+            model_names[self.model1.value[0]],
+            model_names[self.model2.value[0]],
+            ]
+        if self.model3.value[0] > 0:
+            models.append(model_names[self.model3.value[0]-1])
+
         args = dict(
             models=models,
-            alpha=self.alpha.value,
-            interp=self.interpolations[self.merge_method.value[0]],
-            force=self.force.value,
-            merged_model_name=self.merged_model_name.value,
+            alpha = self.alpha.value,
+            interp = self.interpolations[self.merge_method.value[0]],
+            force = self.force.value,
+            merged_model_name = self.merged_model_name.value,
         )
         return args
 
@@ -289,15 +364,18 @@ def check_for_overwrite(self) -> bool:
                 f"The chosen merged model destination, {model_out}, is already in use. Overwrite?"
             )
 
-    def validate_field_values(self) -> bool:
+    def validate_field_values(self)->bool:
         bad_fields = []
-        selected_models = self.models.value
-        if len(selected_models) < 2 or len(selected_models) > 3:
-            bad_fields.append("Please select two or three models to merge.")
+        model_names = self.model_names
+        selected_models = set((model_names[self.model1.value[0]],model_names[self.model2.value[0]]))
+        if self.model3.value[0] > 0:
+            selected_models.add(model_names[self.model3.value[0]-1])
+        if len(selected_models) < 2:
+            bad_fields.append(f'Please select two or three DIFFERENT models to compare. You selected {selected_models}')
         if len(bad_fields) > 0:
-            message = "The following problems were detected and must be corrected:"
+            message = 'The following problems were detected and must be corrected:'
             for problem in bad_fields:
-                message += f"\n* {problem}"
+                message += f'\n* {problem}'
             npyscreen.notify_confirm(message)
             return False
         else:
@@ -322,10 +400,9 @@ def __init__(self):
         )  # precision doesn't really matter here
 
     def onStart(self):
-        npyscreen.setTheme(npyscreen.Themes.DefaultTheme)
+        npyscreen.setTheme(npyscreen.Themes.ElegantTheme)
         self.main = self.addForm("MAIN", mergeModelsForm, name="Merge Models Settings")
 
-
 def run_gui(args: Namespace):
     mergeapp = Mergeapp()
     mergeapp.run()
@@ -338,8 +415,8 @@ def run_gui(args: Namespace):
 def run_cli(args: Namespace):
     assert args.alpha >= 0 and args.alpha <= 1.0, "alpha must be between 0 and 1"
     assert (
-        len(args.models) >= 1 and len(args.models) <= 3
-    ), "provide 2 or 3 models to merge"
+        args.models and len(args.models) >= 1 and len(args.models) <= 3
+    ), "Please provide the --models argument to list 2 to 3 models to merge. Use --help for full usage."
 
     if not args.merged_model_name:
         args.merged_model_name = "+".join(args.models)
@@ -353,6 +430,7 @@ def run_cli(args: Namespace):
         ), f'A model named "{args.merged_model_name}" already exists. Use --clobber to overwrite.'
 
         merge_diffusion_models_and_commit(**vars(args))
+        print(f'>> Models merged into new model: "{args.merged_model_name}".')
 
 
 def main():
@@ -365,17 +443,22 @@ def main():
     ] = cache_dir  # because not clear the merge pipeline is honoring cache_dir
     args.cache_dir = cache_dir
 
-    try:
-        if args.front_end:
-            run_gui(args)
-        else:
-            run_cli(args)
-        print(f">> Conversion successful. New model is named {args.merged_model_name}")
-    except Exception as e:
-        print(f"** An error occurred while merging the pipelines: {str(e)}")
-        sys.exit(-1)
-    except KeyboardInterrupt:
-        sys.exit(-1)
+    with warnings.catch_warnings():
+        warnings.simplefilter('ignore')
+        try:
+            if args.front_end:
+                run_gui(args)
+            else:
+                run_cli(args)
+            print(f'>> Conversion successful.')
+        except Exception as e:
+            if str(e).startswith('Not enough space'):
+                print('** Not enough horizontal space! Try making the window wider, or relaunch with a smaller starting size.')
+            else:
+                print(f"** An error occurred while merging the pipelines: {str(e)}")
+            sys.exit(-1)
+        except KeyboardInterrupt:
+            sys.exit(-1)
 
 if __name__ == "__main__":
     main()