from rest_framework import serializers

from .models import (
    NodeAssignment,
    Transition,
    Workflow,
    WorkflowInstance,
    WorkflowNode,
    WorkflowObserver,
)


class WorkflowSerializer(serializers.ModelSerializer):
    created_by_info = serializers.SerializerMethodField()

    class Meta:
        model = Workflow
        fields = [
            "id",
            "slug",
            "name",
            "description",
            "is_active",
            "created_by",
            "created_by_info",
        ]
        read_only_fields = ["id"]

    def get_created_by_info(self, obj):
        if obj.created_by_id:
            return {"id": obj.created_by_id, "display": str(obj.created_by)}
        return None


class WorkflowNodeSerializer(serializers.ModelSerializer):
    workflow_info = serializers.SerializerMethodField()

    class Meta:
        model = WorkflowNode
        fields = [
            "id",
            "workflow",
            "workflow_info",
            "name",
            "node_type",
            "min_approvals",
            "approval_strategy",
            "position_x",
            "position_y",
        ]
        read_only_fields = ["id"]

    def get_workflow_info(self, obj):
        return {"id": obj.workflow_id, "slug": obj.workflow.slug, "name": obj.workflow.name}


class TransitionSerializer(serializers.ModelSerializer):
    from_node_info = serializers.SerializerMethodField()
    to_node_info = serializers.SerializerMethodField()

    class Meta:
        model = Transition
        fields = [
            "id",
            "from_node",
            "from_node_info",
            "to_node",
            "to_node_info",
            "condition_slug",
            "is_default",
        ]
        read_only_fields = ["id"]

    def get_from_node_info(self, obj):
        return {"id": obj.from_node_id, "name": obj.from_node.name}

    def get_to_node_info(self, obj):
        return {"id": obj.to_node_id, "name": obj.to_node.name}


class WorkflowInstanceSerializer(serializers.ModelSerializer):
    workflow_info = serializers.SerializerMethodField()
    current_node_info = serializers.SerializerMethodField()
    owner_info = serializers.SerializerMethodField()

    class Meta:
        model = WorkflowInstance
        fields = [
            "id",
            "workflow",
            "workflow_info",
            "current_node",
            "current_node_info",
            "owner",
            "owner_info",
            "status",
            "started_at",
            "completed_at",
            "metadata",
        ]
        read_only_fields = ["id", "started_at", "completed_at"]

    def get_workflow_info(self, obj):
        return {"id": obj.workflow_id, "slug": obj.workflow.slug, "name": obj.workflow.name}

    def get_current_node_info(self, obj):
        if obj.current_node_id:
            return {"id": obj.current_node_id, "name": obj.current_node.name}
        return None

    def get_owner_info(self, obj):
        if obj.owner_id:
            return {"id": obj.owner_id, "display": str(obj.owner)}
        return None


class NodeAssignmentSerializer(serializers.ModelSerializer):
    instance_info = serializers.SerializerMethodField()
    node_info = serializers.SerializerMethodField()
    user_info = serializers.SerializerMethodField()

    class Meta:
        model = NodeAssignment
        fields = [
            "id",
            "instance",
            "instance_info",
            "node",
            "node_info",
            "user",
            "user_info",
            "visit_number",
            "is_required",
            "has_processed",
            "decision",
            "comments",
            "submitted_data",
            "processed_at",
        ]
        read_only_fields = ["id", "processed_at"]

    def get_instance_info(self, obj):
        return {"id": obj.instance_id}

    def get_node_info(self, obj):
        return {"id": obj.node_id, "name": obj.node.name}

    def get_user_info(self, obj):
        return {"id": obj.user_id, "display": str(obj.user)}


class WorkflowObserverSerializer(serializers.ModelSerializer):
    instance_info = serializers.SerializerMethodField()
    user_info = serializers.SerializerMethodField()

    class Meta:
        model = WorkflowObserver
        fields = ["id", "instance", "instance_info", "user", "user_info"]
        read_only_fields = ["id"]

    def get_instance_info(self, obj):
        return {"id": obj.instance_id}

    def get_user_info(self, obj):
        return {"id": obj.user_id, "display": str(obj.user)}