From 2ce52d32e41fb523d1494f45073fd18496e52d35 Mon Sep 17 00:00:00 2001
From: discus0434 <discus0434@gmail.com>
Date: Wed, 19 Oct 2022 16:31:12 +0000
Subject: [PATCH] fix for #3086 failing to load any previous hypernet

---
 modules/hypernetworks/hypernetwork.py | 60 +++++++++++++--------------
 1 file changed, 28 insertions(+), 32 deletions(-)

diff --git a/modules/hypernetworks/hypernetwork.py b/modules/hypernetworks/hypernetwork.py
index 7d519cd9b..74300122b 100644
--- a/modules/hypernetworks/hypernetwork.py
+++ b/modules/hypernetworks/hypernetwork.py
@@ -24,11 +24,10 @@ class HypernetworkModule(torch.nn.Module):
 
     def __init__(self, dim, state_dict=None, layer_structure=None, add_layer_norm=False):
         super().__init__()
-        if layer_structure is not None:
-            assert layer_structure[0] == 1, "Multiplier Sequence should start with size 1!"
-            assert layer_structure[-1] == 1, "Multiplier Sequence should end with size 1!"
-        else:
-            layer_structure = parse_layer_structure(dim, state_dict)
+
+        assert layer_structure is not None, "layer_structure mut not be None"
+        assert layer_structure[0] == 1, "Multiplier Sequence should start with size 1!"
+        assert layer_structure[-1] == 1, "Multiplier Sequence should end with size 1!"
 
         linears = []
         for i in range(len(layer_structure) - 1):
@@ -39,23 +38,30 @@ class HypernetworkModule(torch.nn.Module):
         self.linear = torch.nn.Sequential(*linears)
 
         if state_dict is not None:
-            try:
-                self.load_state_dict(state_dict)
-            except RuntimeError:
-                self.try_load_previous(state_dict)
+            self.fix_old_state_dict(state_dict)
+            self.load_state_dict(state_dict)
         else:
             for layer in self.linear:
-                layer.weight.data.normal_(mean = 0.0, std = 0.01)
+                layer.weight.data.normal_(mean=0.0, std=0.01)
                 layer.bias.data.zero_()
 
         self.to(devices.device)
 
-    def try_load_previous(self, state_dict):
-        states = self.state_dict()
-        states['linear.0.bias'].copy_(state_dict['linear1.bias'])
-        states['linear.0.weight'].copy_(state_dict['linear1.weight'])
-        states['linear.1.bias'].copy_(state_dict['linear2.bias'])
-        states['linear.1.weight'].copy_(state_dict['linear2.weight'])
+    def fix_old_state_dict(self, state_dict):
+        changes = {
+            'linear1.bias': 'linear.0.bias',
+            'linear1.weight': 'linear.0.weight',
+            'linear2.bias': 'linear.1.bias',
+            'linear2.weight': 'linear.1.weight',
+        }
+
+        for fr, to in changes.items():
+            x = state_dict.get(fr, None)
+            if x is None:
+                continue
+
+            del state_dict[fr]
+            state_dict[to] = x
 
     def forward(self, x):
         return x + self.linear(x) * self.multiplier
@@ -71,18 +77,6 @@ def apply_strength(value=None):
     HypernetworkModule.multiplier = value if value is not None else shared.opts.sd_hypernetwork_strength
 
 
-def parse_layer_structure(dim, state_dict):
-    i = 0
-    layer_structure = [1]
-
-    while (key := "linear.{}.weight".format(i)) in state_dict:
-        weight = state_dict[key]
-        layer_structure.append(len(weight) // dim)
-        i += 1
-
-    return layer_structure
-
-
 class Hypernetwork:
     filename = None
     name = None
@@ -135,17 +129,18 @@ class Hypernetwork:
 
         state_dict = torch.load(filename, map_location='cpu')
 
+        self.layer_structure = state_dict.get('layer_structure', [1, 2, 1])
+        self.add_layer_norm = state_dict.get('is_layer_norm', False)
+
         for size, sd in state_dict.items():
             if type(size) == int:
                 self.layers[size] = (
-                    HypernetworkModule(size, sd[0], state_dict["layer_structure"], state_dict["is_layer_norm"]),
-                    HypernetworkModule(size, sd[1], state_dict["layer_structure"], state_dict["is_layer_norm"]),
+                    HypernetworkModule(size, sd[0], self.layer_structure, self.add_layer_norm),
+                    HypernetworkModule(size, sd[1], self.layer_structure, self.add_layer_norm),
                 )
 
         self.name = state_dict.get('name', self.name)
         self.step = state_dict.get('step', 0)
-        self.layer_structure = state_dict.get('layer_structure', None)
-        self.add_layer_norm = state_dict.get('is_layer_norm', False)
         self.sd_checkpoint = state_dict.get('sd_checkpoint', None)
         self.sd_checkpoint_name = state_dict.get('sd_checkpoint_name', None)
 
@@ -244,6 +239,7 @@ def stack_conds(conds):
 
     return torch.stack(conds)
 
+
 def train_hypernetwork(hypernetwork_name, learn_rate, batch_size, data_root, log_directory, training_width, training_height, steps, create_image_every, save_hypernetwork_every, template_file, preview_from_txt2img, preview_prompt, preview_negative_prompt, preview_steps, preview_sampler_index, preview_cfg_scale, preview_seed, preview_width, preview_height):
     assert hypernetwork_name, 'hypernetwork not selected'