use crate::ffi::{
    ffi_arc_dyn_getter, ffi_vec_stringkey_getters, ffi_vec_value_getters, BorrowedPtr, ExternPointer,
    IdentifiablePointer, NativeResult, OwnedPtr,
};
use crate::static_data::{Form, FormImpl, LearnableMoves, StaticStatisticSet, TypeIdentifier};
use crate::StringKey;
use anyhow::anyhow;
use hashbrown::HashSet;
use std::ffi::{c_char, CStr, CString};
use std::ptr::drop_in_place;
use std::sync::Arc;

/// Instantiates a new form.
#[no_mangle]
unsafe extern "C" fn form_new(
    name: *const c_char,
    height: f32,
    weight: f32,
    base_experience: u32,
    types: *const TypeIdentifier,
    types_length: usize,
    base_stats: OwnedPtr<StaticStatisticSet<u16>>,
    abilities: *const BorrowedPtr<c_char>,
    abilities_length: usize,
    hidden_abilities: *const BorrowedPtr<c_char>,
    hidden_abilities_length: usize,
    moves: OwnedPtr<Box<dyn LearnableMoves>>,
    flags: *const *const c_char,
    flags_length: usize,
) -> NativeResult<IdentifiablePointer<Arc<dyn Form>>> {
    let name: StringKey = match CStr::from_ptr(name).to_str() {
        Ok(name) => name.into(),
        Err(_) => return NativeResult::err(anyhow!("Unable to convert name to string")),
    };

    let abilities = std::slice::from_raw_parts(abilities, abilities_length);
    let mut abilities_vec = Vec::with_capacity(abilities_length);
    for ability in abilities {
        abilities_vec.push(CStr::from_ptr(*ability).into())
    }
    let hidden_abilities = std::slice::from_raw_parts(hidden_abilities, hidden_abilities_length);
    let mut hidden_abilities_vec = Vec::with_capacity(hidden_abilities_length);
    for ability in hidden_abilities {
        hidden_abilities_vec.push(CStr::from_ptr(*ability).into())
    }

    let flags = std::slice::from_raw_parts(flags, flags_length);
    let mut flags_set: HashSet<StringKey> = HashSet::with_capacity(flags_length);
    for flag in flags {
        let flag = match CStr::from_ptr(*flag).to_str() {
            Ok(flag) => flag,
            Err(_) => return NativeResult::err(anyhow!("Unable to convert flag to string")),
        };
        flags_set.insert(flag.into());
    }

    let a: Arc<dyn Form> = Arc::new(FormImpl::new(
        &name,
        height,
        weight,
        base_experience,
        std::slice::from_raw_parts(types, types_length).to_vec(),
        *Box::from_raw(base_stats),
        abilities_vec,
        hidden_abilities_vec,
        *Box::from_raw(moves),
        flags_set,
    ));
    NativeResult::ok(a.into())
}

/// Drops a reference count for a form.
#[no_mangle]
unsafe extern "C" fn form_drop(ptr: OwnedPtr<Arc<dyn Form>>) {
    drop_in_place(ptr)
}

/// The name of the form.
#[no_mangle]
unsafe extern "C" fn form_name(ptr: ExternPointer<Arc<dyn Form>>) -> NativeResult<OwnedPtr<c_char>> {
    let name = ptr.as_ref().name();
    match CString::new(name.str()) {
        Ok(name) => NativeResult::ok(name.into_raw()),
        Err(_) => NativeResult::err(anyhow!("Unable to convert name `{}` to CString", name.str())),
    }
}

ffi_arc_dyn_getter!(Form, height, f32);
ffi_arc_dyn_getter!(Form, weight, f32);
ffi_arc_dyn_getter!(Form, base_experience, u32);

ffi_vec_value_getters!(Form, dyn Form, types, TypeIdentifier);

/// The inherent values of a form of species that are used for the stats of a Pokemon.
#[no_mangle]
unsafe extern "C" fn form_base_stats(
    ptr: ExternPointer<Arc<dyn Form>>,
) -> IdentifiablePointer<Arc<StaticStatisticSet<u16>>> {
    ptr.as_ref().base_stats().clone().into()
}

ffi_vec_stringkey_getters!(Form, abilities);
ffi_vec_stringkey_getters!(Form, hidden_abilities);

/// The moves a Pokemon with this form can learn.
#[no_mangle]
extern "C" fn form_moves(ptr: ExternPointer<Arc<dyn Form>>) -> BorrowedPtr<Box<dyn LearnableMoves>> {
    ptr.as_ref().moves() as *const Box<dyn LearnableMoves>
}

/// Check if the form has a specific flag set.
#[no_mangle]
unsafe extern "C" fn form_has_flag(ptr: ExternPointer<Arc<dyn Form>>, flag: *const c_char) -> u8 {
    let flag = CStr::from_ptr(flag).into();
    u8::from(ptr.as_ref().has_flag(&flag))
}