import math

import bpy

from ... import config
from ...core import Check, Issue, contexts


class ModifiersCheck(Check):
    id = "modifiers"
    label = "Modifiers"
    description = "No modifiers other than Subdivision Surface and Multiresolution."
    category = "Objects"
    contexts = contexts.ASSET - {contexts.CHAR_LINEART}
    fix_description = "Apply the modifiers that are not allowed"
    # Config key holding the allowed modifier types; subclasses change it.
    allowed_config_key = "ALLOWED_MODIFIERS"

    def run(self, ctx):
        allowed = getattr(config, self.allowed_config_key)
        for ob in ctx.objects():
            names = [m.name for m in ob.modifiers if m.type not in allowed]
            if names:
                yield Issue.for_id(
                    f"{ob.name}: {', '.join(names)}",
                    ob,
                    data={"modifiers": names},
                )

    def fix(self, ctx, issues):
        failed = []
        for issue in issues:
            ob = issue.get_id()
            if ob is None:
                continue
            for name in issue.data["modifiers"]:
                try:
                    with bpy.context.temp_override(object=ob, active_object=ob, selected_objects=[ob]):
                        bpy.ops.object.modifier_apply(modifier=name)
                except RuntimeError as exc:
                    failed.append(f"{ob.name} / {name}: {str(exc).strip()}")
        return failed


class ApplyTransformCheck(Check):
    id = "apply_transform"
    label = "Transforms applied"
    description = "Rotation and scale (and location if set in config) of geometry objects are applied."
    category = "Objects"
    contexts = contexts.ASSET
    fix_description = "Apply the transforms (multi-user data is reported, not changed)"

    def run(self, ctx):
        tolerance = config.TRANSFORM_TOLERANCE
        channels = config.APPLY_TRANSFORM
        for ob in ctx.objects(*config.APPLY_TRANSFORM_TYPES):
            loc, rot, scale = ob.matrix_basis.decompose()
            problems = []
            if channels.get("location") and loc.length > tolerance:
                problems.append("location")
            if channels.get("rotation") and min(rot.angle, math.tau - rot.angle) > tolerance:
                problems.append("rotation")
            if channels.get("scale") and any(abs(s - 1.0) > tolerance for s in scale):
                problems.append("scale")
            if problems:
                yield Issue.for_id(f"{ob.name}: {', '.join(problems)} not applied", ob)

    def fix(self, ctx, issues):
        failed = []
        channels = config.APPLY_TRANSFORM
        for issue in issues:
            ob = issue.get_id()
            if ob is None:
                continue
            if ob.data is not None and ob.data.users > 1:
                failed.append(f"{ob.name}: data shared by {ob.data.users} users, apply by hand")
                continue
            try:
                with bpy.context.temp_override(
                    object=ob, active_object=ob, selected_objects=[ob], selected_editable_objects=[ob]
                ):
                    bpy.ops.object.transform_apply(
                        location=bool(channels.get("location")),
                        rotation=bool(channels.get("rotation")),
                        scale=bool(channels.get("scale")),
                    )
            except RuntimeError as exc:
                failed.append(f"{ob.name}: {str(exc).strip()}")
        return failed


class LightCameraCheck(Check):
    id = "lights_cameras"
    label = "Lights & cameras"
    description = "Asset files contain no lights or cameras."
    category = "Objects"
    contexts = contexts.ASSET
    fix_description = "Delete the lights and cameras"

    def run(self, ctx):
        for ob in ctx.objects(*config.FORBIDDEN_ASSET_OBJECT_TYPES):
            yield Issue.for_id(f"{ob.type.capitalize()} '{ob.name}' must be removed", ob)

    def fix(self, ctx, issues):
        for issue in issues:
            ob = issue.get_id()
            if ob is not None:
                bpy.data.objects.remove(ob, do_unlink=True)