Extract row rendering policy

row_rendering.py

@@ -0,0 +1,113 @@
+from __future__ import annotations
+
+from string import Formatter
+from typing import Any
+
+try:
+    from . import row_camera as row_camera_policy
+except ImportError:  # Allows local smoke tests from the repository root.
+    import row_camera as row_camera_policy
+
+
+GENERIC_POSITIVE_SUFFIX = (
+    "Use crisp clean comic linework, detailed hatching, soft blended shading, "
+    "pastel skin tones, muted blues and pinks, warm sensual lighting, and tactile textured paper."
+)
+
+SINGLE_TEMPLATE = (
+    "A {subject}: {style}, {age}, {body_phrase}, {skin}, {hair}, {eyes}. "
+    "{item_label}: {item}. Scene: {scene}. Pose: {pose}. Facial expression: {expression}. "
+    "Composition: {composition_prompt}. {positive_suffix} Avoid: {negative_prompt}."
+)
+
+COUPLE_TEMPLATE = (
+    "{subject_phrase}: {style}. Ages: {age}. Body types: {body}. {item_label}: {item}. "
+    "Scene: {scene}. Pose: {pose}. Facial expressions: {expression}. "
+    "Composition: {composition_prompt}. {positive_suffix} Avoid: {negative_prompt}."
+)
+
+GROUP_TEMPLATE = (
+    "{subject_phrase}: {style}, ages {age}, diverse adult body types. {item_label}: {item}. "
+    "Scene: {scene}. Facial expressions: {expression}. Composition: {composition_prompt}. "
+    "{positive_suffix} Avoid: {negative_prompt}."
+)
+
+LAYOUT_TEMPLATE = (
+    "{item}: {style}, adults only, clean designed composition. Scene: {scene}. "
+    "Facial expression: {expression}. Composition: {composition}. {positive_suffix} "
+    "Avoid: {negative_prompt}. Use no readable text unless the layout naturally needs small decorative placeholder marks."
+)
+
+DEFAULT_CAPTION_TEMPLATE = (
+    "{trigger}, {subject_phrase}, {age}, {item}, {scene}, {composition}, coloured pencil comic illustration"
+)
+
+
+class SafeFormatDict(dict):
+    def __missing__(self, key: str) -> str:
+        return "{" + key + "}"
+
+
+def format_template(template: str, context: dict[str, Any]) -> str:
+    fields = {key for _, key, _, _ in Formatter().parse(template) if key}
+    safe_context = SafeFormatDict({key: str(value) for key, value in context.items()})
+    for field in fields:
+        safe_context.setdefault(field, "{" + field + "}")
+    return template.format_map(safe_context)
+
+
+def default_prompt_template(subject_type: str) -> str:
+    if subject_type in ("woman", "man"):
+        return SINGLE_TEMPLATE
+    if subject_type == "couple":
+        return COUPLE_TEMPLATE
+    if subject_type == "group":
+        return GROUP_TEMPLATE
+    return LAYOUT_TEMPLATE
+
+
+def prompt_template_for(item: Any, subcategory: dict[str, Any], category: dict[str, Any], subject_type: str) -> str:
+    if isinstance(item, dict) and "prompt_template" in item:
+        return str(item["prompt_template"])
+    template = str(subcategory.get("prompt_template") or category.get("prompt_template") or "")
+    return template or default_prompt_template(subject_type)
+
+
+def caption_template_for(item: Any, subcategory: dict[str, Any], category: dict[str, Any]) -> str:
+    return str(
+        (item.get("caption_template") if isinstance(item, dict) else None)
+        or subcategory.get("caption_template")
+        or category.get("caption_template")
+        or DEFAULT_CAPTION_TEMPLATE
+    )
+
+
+def render_prompt_caption(
+    *,
+    item: Any,
+    subcategory: dict[str, Any],
+    category: dict[str, Any],
+    subject_type: str,
+    context: dict[str, Any],
+    cast_descriptor_text: str = "",
+    pov_prompt_directive: str = "",
+) -> dict[str, str]:
+    prompt_template = prompt_template_for(item, subcategory, category, subject_type)
+    caption_template = caption_template_for(item, subcategory, category)
+
+    prompt = format_template(prompt_template, context)
+    if subject_type == "configured_cast" and cast_descriptor_text and "{cast_descriptors}" not in prompt_template:
+        prompt = row_camera_policy.insert_positive_directive(prompt, f"Characters: {cast_descriptor_text}.")
+    if subject_type == "configured_cast" and pov_prompt_directive:
+        prompt = row_camera_policy.insert_positive_directive(prompt, pov_prompt_directive)
+
+    caption = format_template(caption_template, context)
+    if subject_type == "configured_cast" and cast_descriptor_text and "{cast_descriptors}" not in caption_template:
+        caption = f"{caption.rstrip()}, {cast_descriptor_text}"
+
+    return {
+        "prompt": prompt,
+        "caption": caption,
+        "prompt_template": prompt_template,
+        "caption_template": caption_template,
+    }