graphql-schema-diff 0.5.0

use cynic_parser::type_system::SchemaDefinition;

use crate::ChangeKind;

use super::{
    DefinitionOrExtension, INDENTATION,
    directives::{DirectiveContext, patch_directives},
    paths::Paths,
};

pub(super) fn patch_schema_definition<T: AsRef<str>>(
    definition: SchemaDefinition<'_>,
    definition_or_extension: super::DefinitionOrExtension,
    schema: &mut String,
    paths: &Paths<'_, T>,
) {
    let mut new_query_type = None;
    let mut new_mutation_type = None;
    let mut new_subscription_type = None;

    let prefix = match definition_or_extension {
        DefinitionOrExtension::Extension => ":schema[0]",
        DefinitionOrExtension::Definition => ":schema",
    };

    for change in paths.iter_exact([prefix, "", "", ""]) {
        match change.kind() {
            ChangeKind::ChangeQueryType => {
                new_query_type = Some(change.resolved_str());
            }
            ChangeKind::ChangeMutationType => {
                new_mutation_type = Some(change.resolved_str());
            }
            ChangeKind::ChangeSubscriptionType => {
                new_subscription_type = Some(change.resolved_str());
            }
            ChangeKind::RemoveSchemaDefinition if definition_or_extension.is_definition() => return,
            ChangeKind::RemoveSchemaExtension if definition_or_extension.is_extension() => return,
            _ => (),
        }
    }

    if let DefinitionOrExtension::Extension = definition_or_extension {
        schema.push_str("extend ");
    }

    schema.push_str("schema");

    patch_directives(
        definition.directives(),
        schema,
        paths,
        DirectiveContext::Type(":schema"),
    );

    let any_root_type_defined = new_query_type.is_some()
        || new_mutation_type.is_some()
        || new_subscription_type.is_some()
        || definition.query_type().is_some()
        || definition.mutation_type().is_some()
        || definition.subscription_type().is_some();

    if !any_root_type_defined {
        schema.push_str("\n\n");
        return;
    }

    schema.push_str(" {\n");

    for (operation_name, maybe_replacement, in_source) in [
        ("query", new_query_type, definition.query_type()),
        ("mutation", new_mutation_type, definition.mutation_type()),
        ("subscription", new_subscription_type, definition.subscription_type()),
    ] {
        if let Some(type_name) = maybe_replacement
            .or_else(|| in_source.map(|ty| ty.named_type()))
            .filter(|name| !name.is_empty())
        {
            schema.push_str(INDENTATION);
            schema.push_str(operation_name);
            schema.push_str(": ");
            schema.push_str(type_name);
            schema.push('\n')
        }
    }

    schema.push_str("}\n\n");
}