/*
 * The MIT License (MIT)
 * Copyright (C) 2024 Huawei Device Co., Ltd.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 */

use std::mem;
use std::ops::{Deref, DerefMut};
use std::ptr;

use super::{Value, ValueType};
use crate::bindgen_runtime::ValidateNapiValue;
use crate::{
  bindgen_runtime::TypeName, check_status, sys, Error, JsUnknown, NapiValue, Ref, Result, Status,
};

pub struct JsBuffer(pub(crate) Value);

impl TypeName for JsBuffer {
  fn type_name() -> &'static str {
    "Buffer"
  }

  fn value_type() -> ValueType {
    ValueType::Object
  }
}

impl ValidateNapiValue for JsBuffer {
  unsafe fn validate(env: sys::napi_env, napi_val: sys::napi_value) -> Result<sys::napi_value> {
    let mut is_buffer = false;
    check_status!(unsafe { sys::napi_is_buffer(env, napi_val, &mut is_buffer) })?;
    if !is_buffer {
      return Err(Error::new(
        Status::InvalidArg,
        "Value is not a buffer".to_owned(),
      ));
    }
    Ok(ptr::null_mut())
  }
}

pub struct JsBufferValue {
  pub(crate) value: JsBuffer,
  data: mem::ManuallyDrop<Vec<u8>>,
}

impl JsBuffer {
  pub fn into_value(self) -> Result<JsBufferValue> {
    let mut data = ptr::null_mut();
    let mut len: usize = 0;
    check_status!(unsafe {
      sys::napi_get_buffer_info(self.0.env, self.0.value, &mut data, &mut len)
    })?;
    Ok(JsBufferValue {
      data: mem::ManuallyDrop::new(unsafe { Vec::from_raw_parts(data as *mut _, len, len) }),
      value: self,
    })
  }

  pub fn into_ref(self) -> Result<Ref<JsBufferValue>> {
    Ref::new(self.0, 1, self.into_value()?)
  }
}

impl JsBufferValue {
  pub fn new(value: JsBuffer, data: mem::ManuallyDrop<Vec<u8>>) -> Self {
    JsBufferValue { value, data }
  }

  pub fn into_raw(self) -> JsBuffer {
    self.value
  }

  pub fn into_unknown(self) -> JsUnknown {
    unsafe { JsUnknown::from_raw_unchecked(self.value.0.env, self.value.0.value) }
  }
}

impl AsRef<[u8]> for JsBufferValue {
  fn as_ref(&self) -> &[u8] {
    self.data.as_slice()
  }
}

impl AsMut<[u8]> for JsBufferValue {
  fn as_mut(&mut self) -> &mut [u8] {
    self.data.as_mut_slice()
  }
}

impl Deref for JsBufferValue {
  type Target = [u8];

  fn deref(&self) -> &Self::Target {
    self.data.as_slice()
  }
}

impl DerefMut for JsBufferValue {
  fn deref_mut(&mut self) -> &mut Self::Target {
    self.data.as_mut_slice()
  }
}