"""
Rendering & Lighting Tools
Fine-grained control over scene lighting, materials, background, fog,
post-processing effects, and camera effects.
"""
from typing import Dict, Any, Optional
from backend.storage import storage


def add_light(
    scene_id: str,
    light_type: str,
    name: str,
    color: str = "#ffffff",
    intensity: float = 1.0,
    position: Optional[Dict[str, float]] = None,
    target: Optional[Dict[str, float]] = None,
    cast_shadow: bool = False,
    spot_angle: Optional[float] = None
) -> Dict[str, Any]:
    """
    Implementation: Add a new light source to the scene

    Args:
        scene_id: ID of the scene
        light_type: "ambient" | "directional" | "point" | "spot"
        name: Light identifier (e.g., "Torch1", "MainLight")
        color: Hex color (default: "#ffffff")
        intensity: Brightness 0.0-2.0 (default: 1.0)
        position: Position for directional/point/spot lights
        target: Target position for directional/spot lights
        cast_shadow: Enable shadows (default: False)
        spot_angle: Cone angle in degrees (spot lights only)

    Returns:
        Dictionary with light details and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    # Validate light type
    valid_types = ["ambient", "directional", "point", "spot"]
    if light_type not in valid_types:
        raise ValueError(f"Invalid light_type '{light_type}'. Must be one of: {valid_types}")

    # Check for duplicate name
    if "lights" not in scene:
        scene["lights"] = []

    for light in scene["lights"]:
        if light.get("name") == name:
            raise ValueError(f"Light with name '{name}' already exists. Use update_light() to modify it.")

    # Create light object
    light_obj = {
        "name": name,
        "light_type": light_type,
        "color": color,
        "intensity": intensity,
        "cast_shadow": cast_shadow
    }

    # Add position for non-ambient lights
    if light_type != "ambient":
        if position:
            light_obj["position"] = position
        else:
            # Default positions
            defaults = {
                "directional": {"x": 50, "y": 50, "z": 50},
                "point": {"x": 0, "y": 5, "z": 0},
                "spot": {"x": 0, "y": 5, "z": 0}
            }
            light_obj["position"] = defaults.get(light_type, {"x": 0, "y": 5, "z": 0})

    # Add target for directional/spot lights
    if light_type in ["directional", "spot"] and target:
        light_obj["target"] = target

    # Add spot angle for spot lights
    if light_type == "spot":
        light_obj["spot_angle"] = spot_angle if spot_angle else 45.0

    scene["lights"].append(light_obj)
    storage.save(scene)

    return {
        "scene_id": scene_id,
        "message": f"Added {light_type} light '{name}' to scene",
        "light": light_obj
    }


def remove_light(scene_id: str, light_name: str) -> Dict[str, Any]:
    """
    Implementation: Remove a light from the scene

    Args:
        scene_id: ID of the scene
        light_name: Name of light to remove

    Returns:
        Dictionary with confirmation message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "lights" not in scene or not scene["lights"]:
        raise ValueError(f"Scene has no lights to remove")

    # Find and remove light
    original_count = len(scene["lights"])
    scene["lights"] = [light for light in scene["lights"] if light.get("name") != light_name]

    if len(scene["lights"]) == original_count:
        raise ValueError(f"Light '{light_name}' not found in scene")

    storage.save(scene)

    return {
        "scene_id": scene_id,
        "message": f"Removed light '{light_name}' from scene",
        "light_name": light_name
    }


def update_light(
    scene_id: str,
    light_name: str,
    color: Optional[str] = None,
    intensity: Optional[float] = None,
    position: Optional[Dict[str, float]] = None,
    cast_shadow: Optional[bool] = None
) -> Dict[str, Any]:
    """
    Implementation: Update existing light properties

    Args:
        scene_id: ID of the scene
        light_name: Name of light to update
        color: New color (optional)
        intensity: New intensity (optional)
        position: New position (optional)
        cast_shadow: Enable/disable shadows (optional)

    Returns:
        Dictionary with updated light and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "lights" not in scene or not scene["lights"]:
        raise ValueError(f"Scene has no lights")

    # Find light
    light = None
    for l in scene["lights"]:
        if l.get("name") == light_name:
            light = l
            break

    if not light:
        raise ValueError(f"Light '{light_name}' not found in scene")

    # Update properties
    updated_props = []
    if color is not None:
        light["color"] = color
        updated_props.append(f"color={color}")

    if intensity is not None:
        light["intensity"] = intensity
        updated_props.append(f"intensity={intensity}")

    if position is not None:
        light["position"] = position
        updated_props.append(f"position={position}")

    if cast_shadow is not None:
        light["cast_shadow"] = cast_shadow
        updated_props.append(f"shadows={'on' if cast_shadow else 'off'}")

    storage.save(scene)

    return {
        "scene_id": scene_id,
        "message": f"Updated light '{light_name}': {', '.join(updated_props)}",
        "light": light
    }


def get_lights(scene_id: str) -> Dict[str, Any]:
    """
    Implementation: Get all lights in the scene

    Args:
        scene_id: ID of the scene

    Returns:
        Dictionary with list of all lights
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    lights = scene.get("lights", [])

    return {
        "scene_id": scene_id,
        "lights": lights,
        "count": len(lights)
    }


def update_object_material(
    scene_id: str,
    object_id: str,
    color: Optional[str] = None,
    metalness: Optional[float] = None,
    roughness: Optional[float] = None,
    opacity: Optional[float] = None,
    emissive: Optional[str] = None,
    emissive_intensity: Optional[float] = None
) -> Dict[str, Any]:
    """
    Implementation: Update an object's material properties

    Args:
        scene_id: ID of the scene
        object_id: Object to update
        color: Hex color (optional)
        metalness: 0.0-1.0 (optional)
        roughness: 0.0-1.0 (optional)
        opacity: 0.0-1.0 (optional)
        emissive: Emissive color for glow (optional)
        emissive_intensity: Glow strength (optional)

    Returns:
        Dictionary with updated material and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "objects" not in scene or not scene["objects"]:
        raise ValueError(f"Scene has no objects")

    # Find object
    obj = None
    for o in scene["objects"]:
        if o.get("object_id") == object_id:
            obj = o
            break

    if not obj:
        raise ValueError(f"Object '{object_id}' not found in scene")

    # Ensure material exists
    if "material" not in obj:
        obj["material"] = {}

    # Update material properties
    updated_props = []

    if color is not None:
        obj["material"]["color"] = color
        updated_props.append(f"color={color}")

    if metalness is not None:
        obj["material"]["metalness"] = max(0.0, min(1.0, metalness))
        updated_props.append(f"metalness={metalness}")

    if roughness is not None:
        obj["material"]["roughness"] = max(0.0, min(1.0, roughness))
        updated_props.append(f"roughness={roughness}")

    if opacity is not None:
        obj["material"]["opacity"] = max(0.0, min(1.0, opacity))
        updated_props.append(f"opacity={opacity}")

    if emissive is not None:
        obj["material"]["emissive"] = emissive
        updated_props.append(f"emissive={emissive}")

    if emissive_intensity is not None:
        obj["material"]["emissive_intensity"] = emissive_intensity
        updated_props.append(f"emissive_intensity={emissive_intensity}")

    storage.save(scene)

    return {
        "scene_id": scene_id,
        "object_id": object_id,
        "message": f"Updated material: {', '.join(updated_props)}",
        "material": obj["material"]
    }


def set_background_color(
    scene_id: str,
    color: Optional[str] = None,
    bg_type: str = "solid",
    gradient_top: Optional[str] = None,
    gradient_bottom: Optional[str] = None
) -> Dict[str, Any]:
    """
    Implementation: Set scene background color

    Args:
        scene_id: ID of the scene
        color: Hex color for solid background
        bg_type: "solid" | "gradient"
        gradient_top: Top color for gradient
        gradient_bottom: Bottom color for gradient

    Returns:
        Dictionary with background settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "environment" not in scene:
        scene["environment"] = {}

    if bg_type == "gradient":
        if not gradient_top or not gradient_bottom:
            raise ValueError("gradient_top and gradient_bottom are required for gradient backgrounds")

        scene["environment"]["background_type"] = "gradient"
        scene["environment"]["background_gradient_top"] = gradient_top
        scene["environment"]["background_gradient_bottom"] = gradient_bottom

        message = f"Set background to gradient: {gradient_top} → {gradient_bottom}"
    else:
        if not color:
            raise ValueError("color is required for solid backgrounds")

        scene["environment"]["background_type"] = "solid"
        scene["environment"]["background_color"] = color

        message = f"Set background to {color}"

    storage.save(scene)

    return {
        "scene_id": scene_id,
        "message": message,
        "background": scene["environment"]
    }


def set_fog(
    scene_id: str,
    enabled: bool,
    color: Optional[str] = None,
    near: Optional[float] = None,
    far: Optional[float] = None,
    density: Optional[float] = None
) -> Dict[str, Any]:
    """
    Implementation: Set atmospheric fog

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable fog
        color: Fog color (default: "#aaaaaa")
        near: Start distance for linear fog
        far: End distance for linear fog
        density: Density for exponential fog

    Returns:
        Dictionary with fog settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "environment" not in scene:
        scene["environment"] = {}

    if "fog" not in scene["environment"]:
        scene["environment"]["fog"] = {}

    fog = scene["environment"]["fog"]
    fog["enabled"] = enabled

    if enabled:
        fog["color"] = color if color else "#aaaaaa"

        # Determine fog type
        if density is not None:
            fog["type"] = "exponential"
            fog["density"] = density
            message = f"Enabled exponential fog (density={density}, color={fog['color']})"
        elif near is not None and far is not None:
            fog["type"] = "linear"
            fog["near"] = near
            fog["far"] = far
            message = f"Enabled linear fog (near={near}, far={far}, color={fog['color']})"
        else:
            # Default linear fog
            fog["type"] = "linear"
            fog["near"] = 10
            fog["far"] = 50
            message = f"Enabled linear fog (near=10, far=50, color={fog['color']})"
    else:
        message = "Disabled fog"

    storage.save(scene)

    return {
        "scene_id": scene_id,
        "message": message,
        "fog": fog
    }


# =============================================================================
# Post-Processing Tools
# =============================================================================

def set_bloom(
    scene_id: str,
    enabled: bool,
    strength: float = 1.0,
    radius: float = 0.4,
    threshold: float = 0.8
) -> Dict[str, Any]:
    """
    Configure bloom (glow) post-processing effect.

    Bloom creates a glow effect around bright areas of the scene,
    simulating how cameras capture bright light sources.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable bloom
        strength: Bloom intensity (0.0-3.0, default: 1.0)
        radius: Bloom spread/blur radius (0.0-1.0, default: 0.4)
        threshold: Brightness threshold to trigger bloom (0.0-1.0, default: 0.8)

    Returns:
        Dictionary with bloom settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "post_processing" not in scene:
        scene["post_processing"] = {}

    bloom = {
        "enabled": enabled,
        "strength": max(0.0, min(3.0, strength)),
        "radius": max(0.0, min(1.0, radius)),
        "threshold": max(0.0, min(1.0, threshold))
    }
    scene["post_processing"]["bloom"] = bloom

    storage.save(scene)

    if enabled:
        message = f"Enabled bloom (strength={strength}, radius={radius}, threshold={threshold})"
    else:
        message = "Disabled bloom"

    return {
        "scene_id": scene_id,
        "message": message,
        "bloom": bloom
    }


def set_ssao(
    scene_id: str,
    enabled: bool,
    radius: float = 0.5,
    intensity: float = 1.0,
    bias: float = 0.025
) -> Dict[str, Any]:
    """
    Configure Screen Space Ambient Occlusion (SSAO).

    SSAO adds soft shadows in corners and crevices where ambient light
    would naturally be occluded, adding depth and realism.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable SSAO
        radius: Sample radius in world units (0.1-2.0, default: 0.5)
        intensity: Shadow intensity (0.0-2.0, default: 1.0)
        bias: Depth bias to prevent self-occlusion (0.001-0.1, default: 0.025)

    Returns:
        Dictionary with SSAO settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "post_processing" not in scene:
        scene["post_processing"] = {}

    ssao = {
        "enabled": enabled,
        "radius": max(0.1, min(2.0, radius)),
        "intensity": max(0.0, min(2.0, intensity)),
        "bias": max(0.001, min(0.1, bias))
    }
    scene["post_processing"]["ssao"] = ssao

    storage.save(scene)

    if enabled:
        message = f"Enabled SSAO (radius={radius}, intensity={intensity})"
    else:
        message = "Disabled SSAO"

    return {
        "scene_id": scene_id,
        "message": message,
        "ssao": ssao
    }


def set_color_grading(
    scene_id: str,
    enabled: bool,
    brightness: float = 0.0,
    contrast: float = 1.0,
    saturation: float = 1.0,
    hue: float = 0.0,
    exposure: float = 1.0,
    gamma: float = 1.0
) -> Dict[str, Any]:
    """
    Configure color grading post-processing.

    Adjust overall image colors for cinematic looks or stylized effects.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable color grading
        brightness: Brightness adjustment (-1.0 to 1.0, default: 0.0)
        contrast: Contrast multiplier (0.0-2.0, default: 1.0)
        saturation: Color saturation (0.0=grayscale, 1.0=normal, 2.0=vivid)
        hue: Hue shift in degrees (-180 to 180, default: 0)
        exposure: Exposure adjustment (0.0-3.0, default: 1.0)
        gamma: Gamma correction (0.5-2.5, default: 1.0)

    Returns:
        Dictionary with color grading settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "post_processing" not in scene:
        scene["post_processing"] = {}

    color_grading = {
        "enabled": enabled,
        "brightness": max(-1.0, min(1.0, brightness)),
        "contrast": max(0.0, min(2.0, contrast)),
        "saturation": max(0.0, min(2.0, saturation)),
        "hue": max(-180, min(180, hue)),
        "exposure": max(0.0, min(3.0, exposure)),
        "gamma": max(0.5, min(2.5, gamma))
    }
    scene["post_processing"]["color_grading"] = color_grading

    storage.save(scene)

    if enabled:
        adjustments = []
        if brightness != 0.0:
            adjustments.append(f"brightness={brightness}")
        if contrast != 1.0:
            adjustments.append(f"contrast={contrast}")
        if saturation != 1.0:
            adjustments.append(f"saturation={saturation}")
        if hue != 0.0:
            adjustments.append(f"hue={hue}°")
        if exposure != 1.0:
            adjustments.append(f"exposure={exposure}")
        if gamma != 1.0:
            adjustments.append(f"gamma={gamma}")

        if adjustments:
            message = f"Enabled color grading ({', '.join(adjustments)})"
        else:
            message = "Enabled color grading (default settings)"
    else:
        message = "Disabled color grading"

    return {
        "scene_id": scene_id,
        "message": message,
        "color_grading": color_grading
    }


def set_vignette(
    scene_id: str,
    enabled: bool,
    intensity: float = 0.5,
    smoothness: float = 0.5
) -> Dict[str, Any]:
    """
    Configure vignette effect (darkened edges).

    Vignette darkens the corners and edges of the screen,
    drawing focus to the center of the image.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable vignette
        intensity: Darkness of the vignette (0.0-1.0, default: 0.5)
        smoothness: Softness of the vignette edge (0.0-1.0, default: 0.5)

    Returns:
        Dictionary with vignette settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "post_processing" not in scene:
        scene["post_processing"] = {}

    vignette = {
        "enabled": enabled,
        "intensity": max(0.0, min(1.0, intensity)),
        "smoothness": max(0.0, min(1.0, smoothness))
    }
    scene["post_processing"]["vignette"] = vignette

    storage.save(scene)

    if enabled:
        message = f"Enabled vignette (intensity={intensity}, smoothness={smoothness})"
    else:
        message = "Disabled vignette"

    return {
        "scene_id": scene_id,
        "message": message,
        "vignette": vignette
    }


def get_post_processing(scene_id: str) -> Dict[str, Any]:
    """
    Get all post-processing settings for the scene.

    Args:
        scene_id: ID of the scene

    Returns:
        Dictionary with all post-processing settings
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    post_processing = scene.get("post_processing", {})

    return {
        "scene_id": scene_id,
        "post_processing": post_processing
    }


# =============================================================================
# Camera Effects Tools
# =============================================================================

def set_depth_of_field(
    scene_id: str,
    enabled: bool,
    focus_distance: float = 10.0,
    aperture: float = 0.025,
    max_blur: float = 0.01
) -> Dict[str, Any]:
    """
    Configure depth of field (DoF) camera effect.

    Depth of field blurs objects that are not at the focus distance,
    simulating how real camera lenses focus on a specific plane.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable depth of field
        focus_distance: Distance to the focal plane in units (default: 10.0)
        aperture: Aperture size, affects blur amount (0.001-0.1, default: 0.025)
        max_blur: Maximum blur strength (0.0-0.05, default: 0.01)

    Returns:
        Dictionary with DoF settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "camera_effects" not in scene:
        scene["camera_effects"] = {}

    dof = {
        "enabled": enabled,
        "focus_distance": max(0.1, focus_distance),
        "aperture": max(0.001, min(0.1, aperture)),
        "max_blur": max(0.0, min(0.05, max_blur))
    }
    scene["camera_effects"]["depth_of_field"] = dof

    storage.save(scene)

    if enabled:
        message = f"Enabled depth of field (focus={focus_distance}m, aperture={aperture})"
    else:
        message = "Disabled depth of field"

    return {
        "scene_id": scene_id,
        "message": message,
        "depth_of_field": dof
    }


def set_motion_blur(
    scene_id: str,
    enabled: bool,
    intensity: float = 0.5,
    samples: int = 8
) -> Dict[str, Any]:
    """
    Configure motion blur camera effect.

    Motion blur adds blur in the direction of camera or object movement,
    creating a sense of speed and smooth motion.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable motion blur
        intensity: Blur intensity (0.0-2.0, default: 0.5)
        samples: Quality samples for blur (4-32, default: 8)

    Returns:
        Dictionary with motion blur settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "camera_effects" not in scene:
        scene["camera_effects"] = {}

    motion_blur = {
        "enabled": enabled,
        "intensity": max(0.0, min(2.0, intensity)),
        "samples": max(4, min(32, samples))
    }
    scene["camera_effects"]["motion_blur"] = motion_blur

    storage.save(scene)

    if enabled:
        message = f"Enabled motion blur (intensity={intensity}, samples={samples})"
    else:
        message = "Disabled motion blur"

    return {
        "scene_id": scene_id,
        "message": message,
        "motion_blur": motion_blur
    }


def set_chromatic_aberration(
    scene_id: str,
    enabled: bool,
    intensity: float = 0.005
) -> Dict[str, Any]:
    """
    Configure chromatic aberration effect.

    Chromatic aberration simulates lens imperfection by separating
    color channels at the edges of the screen.

    Args:
        scene_id: ID of the scene
        enabled: Enable/disable chromatic aberration
        intensity: Effect strength (0.0-0.05, default: 0.005)

    Returns:
        Dictionary with chromatic aberration settings and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "camera_effects" not in scene:
        scene["camera_effects"] = {}

    chromatic = {
        "enabled": enabled,
        "intensity": max(0.0, min(0.05, intensity))
    }
    scene["camera_effects"]["chromatic_aberration"] = chromatic

    storage.save(scene)

    if enabled:
        message = f"Enabled chromatic aberration (intensity={intensity})"
    else:
        message = "Disabled chromatic aberration"

    return {
        "scene_id": scene_id,
        "message": message,
        "chromatic_aberration": chromatic
    }


def get_camera_effects(scene_id: str) -> Dict[str, Any]:
    """
    Get all camera effects settings for the scene.

    Args:
        scene_id: ID of the scene

    Returns:
        Dictionary with all camera effects settings
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    camera_effects = scene.get("camera_effects", {})

    return {
        "scene_id": scene_id,
        "camera_effects": camera_effects
    }


# =============================================================================
# Toon/Cel Shading Tools
# =============================================================================

def update_material_to_toon(
    scene_id: str,
    object_id: str,
    enabled: bool = True,
    color: Optional[str] = None,
    gradient_steps: int = 3,
    outline: bool = True,
    outline_color: str = "#000000",
    outline_thickness: float = 0.03
) -> Dict[str, Any]:
    """
    Convert an object's material to toon/cel-shaded style.

    Toon shading creates a cartoon-like appearance with discrete shading bands
    instead of smooth gradients, commonly used in anime and cel-animation styles.

    Args:
        scene_id: ID of the scene
        object_id: ID of the object to update
        enabled: Enable/disable toon shading (True to apply, False to revert to standard)
        color: Base color for toon material (optional, keeps existing if not set)
        gradient_steps: Number of shading steps (2=hard, 3=medium, 5=soft, default: 3)
        outline: Add black outline effect (default: True)
        outline_color: Color of the outline (default: "#000000")
        outline_thickness: Thickness of outline (0.01-0.1, default: 0.03)

    Returns:
        Dictionary with updated material info and message
    """
    scene = storage.get(scene_id)
    if not scene:
        raise ValueError(f"Scene '{scene_id}' not found")

    if "objects" not in scene or not scene["objects"]:
        raise ValueError("Scene has no objects")

    # Find object
    obj = None
    for o in scene["objects"]:
        if o.get("id") == object_id or o.get("object_id") == object_id:
            obj = o
            break

    if not obj:
        raise ValueError(f"Object '{object_id}' not found in scene")

    # Ensure material exists
    if "material" not in obj:
        obj["material"] = {}

    # Update toon properties
    if enabled:
        obj["material"]["toon"] = {
            "enabled": True,
            "gradient_steps": max(2, min(10, gradient_steps)),
            "outline": outline,
            "outline_color": outline_color,
            "outline_thickness": max(0.01, min(0.1, outline_thickness))
        }
        if color:
            obj["material"]["color"] = color

        message = f"Applied toon shading to '{object_id}' ({gradient_steps} steps{', with outline' if outline else ''})"
    else:
        obj["material"]["toon"] = {"enabled": False}
        message = f"Disabled toon shading on '{object_id}' (reverted to standard material)"

    storage.save(scene)

    return {
        "scene_id": scene_id,
        "object_id": object_id,
        "message": message,
        "material": obj["material"]
    }