[AB-xxx] adding pat gif generator command

python/components/image-gen/python/endpoints/pat.py

@@ -0,0 +1,80 @@
+from __main__ import app
+
+from PIL import Image, ImageOps
+from flask import request
+import requests
+import validators
+import logging
+import io
+
+from utils import flask_utils
+
+
+sprite_size = 112
+sprites = 5
+allowed_content_length = 4_000_000
+allowed_image_formats = ['image/png', 'image/jpeg', 'image/jpg', 'image/gif']
+
+
+@app.route('/memes/pat/file.gif')  # to directly embed, discord _requires_ this file ending, it seems
+def pat_animated():
+    url = request.args.get('url')
+    if not validators.url(url):
+        return 'no valid url', 400
+    session = requests.Session()
+    response = session.head(url)
+    content_type = response.headers['content-type']
+
+    if content_type not in allowed_image_formats:
+        return f'Incorrect image type {content_type}', 400
+
+    actual_content_length = int(response.headers['content-length'])
+    if actual_content_length > allowed_content_length:
+        return f'Image too large {actual_content_length}', 400
+
+    image_file = requests.get(url, stream=True)
+    input_image = Image.open(io.BytesIO(image_file.content))
+    original_input_image = input_image
+    frame_count = original_input_image.n_frames
+    old_width, old_height = input_image.size
+    with Image.open('resources/img/pet_sprite.png') as pat_background:
+        pat_background = pat_background.convert('RGBA')
+        pat_width, pat_height = pat_background.size
+        pat_ratio = old_width / sprite_size
+        original_background_images = []
+        for i in range(sprites):
+            background_part = pat_background.crop((i * sprite_size, 0, (i + 1) * sprite_size, pat_height))
+            original_background_images.append(background_part)
+        desired_new_pat_width = int(sprite_size * pat_ratio)
+        resized_background_images = []
+        for background_image in original_background_images:
+            if pat_ratio > 1:
+                resized_background = background_image.resize((desired_new_pat_width, pat_height))
+            else:
+                resized_background = ImageOps.contain(background_image, (desired_new_pat_width, pat_height))
+            resized_background_images.append(resized_background)
+        if content_type == 'image/gif':
+            logging.info(f'Rendering pet for gif.')
+            old_frames = []
+            for frame_index in range(frame_count):
+                input_image.seek(frame_index)
+                frame = input_image.convert('RGBA')
+                old_frames.append(frame)
+            frames = []
+            for index, old_frame in enumerate(old_frames):
+                frame = Image.new('RGBA', (old_width, old_height), (0, 0, 0, 0))
+                frame.paste(old_frame, (0, 0), old_frame)
+                frame_background_image = resized_background_images[index % sprites]
+                frame.paste(frame_background_image, (0, 0), frame_background_image)
+                frames.append(frame)
+            return flask_utils.serve_pil_gif_image(frames, int(original_input_image.info['duration']))
+        else:
+            frames = []
+            logging.info(f'Rendering pet for static image.')
+            input_image = input_image.convert('RGBA')
+            for background_image in resized_background_images:
+                frame = Image.new('RGBA', (old_width, old_height), (0, 0, 0, 0))
+                frame.paste(input_image, (0, 0), input_image)
+                frame.paste(background_image, (0, 0), background_image)
+                frames.append(frame)
+            return flask_utils.serve_pil_gif_image(frames, 100)