cinegen/placeholders.py

from __future__ import annotations

import os
import random
import string
import tempfile
from typing import List

import imageio
import numpy as np
from PIL import Image, ImageDraw, ImageFont

from .models import CharacterSpec, SceneBeat, Storyboard

SCENE_TITLES = [
    "Opening Beat",
    "Inciting Incident",
    "Turning Point",
    "Climactic Push",
    "Final Shot",
]

CHARACTER_ARCHETYPES = [
    ("Lead", "Curious protagonist who drives the story."),
    ("Ally", "Supportive partner offering heart and humor."),
    ("Antagonist", "Force of tension that keeps the stakes high."),
]

PALETTE = [
    (28, 35, 51),
    (44, 106, 116),
    (96, 108, 56),
    (224, 142, 73),
    (211, 86, 97),
    (123, 74, 173),
]


def _slugify(text: str) -> str:
    safe = "".join(ch for ch in text if ch.isalnum() or ch in (" ", "-")).strip()
    safe = safe.replace(" ", "-")
    safe = safe.lower()
    return safe or "cinegen"


def normalize_scene_count(scene_count: int | float | str | None) -> int:
    try:
        value = int(float(scene_count))
    except (TypeError, ValueError):
        return 3
    return max(1, value)


def build_stub_storyboard(
    idea: str,
    style: str,
    scene_count: int | float | str,
    inspiration_hint: str | None,
) -> Storyboard:
    normalized_scenes = normalize_scene_count(scene_count)
    random.seed(_slugify(idea) + style + str(normalized_scenes))
    title = idea.title() if idea else f"{style} Short"
    synopsis = (
        f"A {style.lower()} short that transforms the idea '{idea or 'mystery cue'}' "
        "into a compact cinematic arc."
    )
    characters: List[CharacterSpec] = []
    for idx, (role, desc) in enumerate(CHARACTER_ARCHETYPES):
        if idx >= 3 and normalized_scenes <= 3:
            break
        identifier = f"CHAR-{idx+1}"
        name = f"{role} {random.choice(string.ascii_uppercase)}"
        traits = random.sample(
            ["brave", "witty", "restless", "tactical", "empathetic", "curious"], 2
        )
        characters.append(
            CharacterSpec(
                identifier=identifier,
                name=name,
                role=role,
                description=desc,
                traits=traits,
            )
        )

    scenes: List[SceneBeat] = []
    for idx in range(normalized_scenes):
        label = SCENE_TITLES[idx % len(SCENE_TITLES)]
        scene_id = f"SCENE-{idx+1}"
        visuals = (
            f"{style} framing with {random.choice(['soft neon', 'moody shadows', 'bold silhouettes'])}."
        )
        action = f"{characters[0].name if characters else 'The hero'} faces {random.choice(['an unseen threat', 'a tough decision', 'their reflection'])}."
        involved = [char.name for char in characters if random.random() > 0.3][:2] or [
            characters[0].name if characters else "Narrator"
        ]
        scenes.append(
            SceneBeat(
                scene_id=scene_id,
                title=label,
                visuals=visuals,
                action=action,
                characters=involved,
                duration=6,
                mood=random.choice(["hopeful", "tense", "whimsical"]),
                camera=random.choice(["slow push", "steady wide", "handheld close-up"]),
            )
        )

    appendix = (
        f"Aim for motifs inspired by the uploaded reference: {inspiration_hint}."
        if inspiration_hint
        else ""
    )

    return Storyboard(
        title=title,
        synopsis=f"{synopsis} {appendix}".strip(),
        style=style,
        inspiration_hint=inspiration_hint,
        characters=characters,
        scenes=scenes,
    )


def synthesize_character_card(character: CharacterSpec, style: str) -> str:
    width, height = 640, 640
    color = random.choice(PALETTE)
    image = Image.new("RGB", (width, height), color=color)
    draw = ImageDraw.Draw(image)
    font = ImageFont.load_default()
    text = f"{character.name}\n{character.role}\n{', '.join(character.traits)}"
    draw.multiline_text((40, 80), text, fill=(255, 255, 255), font=font, spacing=6)
    draw.text((40, height - 60), f"Style: {style}", fill=(255, 255, 255), font=font)
    tmp_dir = tempfile.mkdtemp(prefix="cinegen-character-")
    path = os.path.join(tmp_dir, f"{_slugify(character.name)}.png")
    image.save(path, format="PNG")
    return path


def create_placeholder_video(scene: SceneBeat, style: str, seconds: int = 4) -> str:
    fps = 6
    frames = fps * seconds
    width, height = 512, 512
    tmp_dir = tempfile.mkdtemp(prefix="cinegen-scene-")
    path = os.path.join(tmp_dir, f"{scene.scene_id.lower()}.mp4")
    rng = np.random.default_rng(sum(ord(c) for c in scene.scene_id))
    with imageio.get_writer(path, fps=fps) as writer:
        for _ in range(frames):
            base_color = rng.integers(60, 220, size=3, dtype=np.uint8)
            frame = np.zeros((height, width, 3), dtype=np.uint8)
            frame[:] = base_color
            image = Image.fromarray(frame)
            draw = ImageDraw.Draw(image)
            font = ImageFont.load_default()
            overlay = f"{scene.title}\n{scene.action[:60]}..."
            draw.multiline_text((24, 24), overlay, fill=(255, 255, 255), font=font, spacing=4)
            draw.text(
                (24, height - 40),
                f"{style} • {scene.characters[0] if scene.characters else 'Solo'}",
                fill=(255, 255, 255),
                font=font,
            )
            writer.append_data(np.array(image))
    return path


def describe_image_reference(image_path: str | None) -> str | None:
    if not image_path or not os.path.exists(image_path):
        return None
    size = os.path.getsize(image_path)
    return f"{os.path.basename(image_path)} ({round(size / 1024, 1)}KB)"