use crate::translation_utils::SignatureIndex;
use cranelift_entity::PrimaryMap;
use std::boxed::Box;

/// Map of signatures to a function's parameter and return types.
pub(crate) type WasmTypes =
    PrimaryMap<SignatureIndex, (Box<[wasmparser::Type]>, Box<[wasmparser::Type]>)>;

/// Contains information decoded from the Wasm module that must be referenced
/// during each Wasm function's translation.
///
/// This is only for data that is maintained by `cranelift-wasm` itself, as
/// opposed to being maintained by the embedder. Data that is maintained by the
/// embedder is represented with `ModuleEnvironment`.
#[derive(Debug)]
pub struct ModuleTranslationState {
    /// A map containing a Wasm module's original, raw signatures.
    ///
    /// This is used for translating multi-value Wasm blocks inside functions,
    /// which are encoded to refer to their type signature via index.
    pub(crate) wasm_types: WasmTypes,
}

impl ModuleTranslationState {
    /// Creates a new empty ModuleTranslationState.
    pub fn new() -> Self {
        Self {
            wasm_types: PrimaryMap::new(),
        }
    }
}