use crate::{
    error::{ArrayError, SizeError},
    C_STRING_FAILURE,
};

use std::ffi::CString;

/// Gets the size of an array by its name from the pd patch which is loaded.
///
/// # Example
/// ```no_run
/// use libpd_rs::array::array_size;
///
/// let size = array_size("my_array").unwrap();
/// ```
///
/// # Errors
///
/// A list of errors that can occur:
/// - [`CouldNotDetermine`](crate::error::SizeError::CouldNotDetermine)
pub fn array_size<T: AsRef<str>>(name: T) -> Result<i32, SizeError> {
    unsafe {
        let name = CString::new(name.as_ref()).expect(C_STRING_FAILURE);
        // Returns size or negative error code if non-existent
        let result = libpd_sys::libpd_arraysize(name.as_ptr());
        if result >= 0 {
            return Ok(result);
        }
        Err(SizeError::CouldNotDetermine)
    }
}

/// Resizes an array found by its name from the pd patch which is loaded.
///
/// Sizes `<= 0` or `> size limit` are clipped to `1`
///
/// # Example
/// ```no_run
/// use libpd_rs::array::{array_size, resize_array};
///
/// resize_array("my_array", 1024).unwrap();
/// let size = array_size("my_array").unwrap();
/// assert_eq!(size, 1024);
///
/// resize_array("my_array", 0).unwrap();
/// let size = array_size("my_array").unwrap();
/// assert_eq!(size, 1);
/// ```
///
/// # Errors
///
/// A list of errors that can occur:
/// - [`CouldNotDetermine`](crate::error::SizeError::CouldNotDetermine)
pub fn resize_array<T: AsRef<str>>(name: T, size: i32) -> Result<(), SizeError> {
    // The size argument is a `long` but bindgen interprets it as i64
    //
    // Also libpd has this,
    // if (MSVC)
    // set(CMAKE_C_FLAGS  "${CMAKE_C_FLAGS} -DHAVE_STRUCT_TIMESPEC")
    // add_definitions("/D_CRT_SECURE_NO_WARNINGS /wd4091 /wd4996")
    // if(${CMAKE_SIZEOF_VOID_P} EQUAL 8)
    //     # Select appropriate long int type on 64-bit Windows
    //     set(CMAKE_C_FLAGS  "${CMAKE_C_FLAGS} -DPD_LONGINTTYPE=\"long long\"")
    // endif()
    // else()
    // set(CMAKE_C_FLAGS         "${CMAKE_C_FLAGS} -Wno-int-to-pointer-cast -Wno-pointer-to-int-cast")
    // set(CMAKE_C_FLAGS_RELEASE "${CMAKE_C_FLAGS} -ffast-math -funroll-loops -fomit-frame-pointer -O3")
    // set(CMAKE_C_FLAGS_DEBUG   "${CMAKE_C_FLAGS} -g -O0")
    // if(NOT APPLE AND NOT WIN32)
    //     set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -Wl,-Bsymbolic")
    // endif()
    // endif()
    //
    // TODO: Find the right approach here. Low-priority
    unsafe {
        let name = CString::new(name.as_ref()).expect(C_STRING_FAILURE);
        // returns 0 on success or negative error code if non-existent
        #[cfg(target_os = "macos")]
        match libpd_sys::libpd_resize_array(name.as_ptr(), i64::from(size)) {
            0 => Ok(()),
            _ => Err(SizeError::CouldNotDetermine),
        }
        #[cfg(target_os = "linux")]
        match libpd_sys::libpd_resize_array(name.as_ptr(), i64::from(size)) {
            0 => Ok(()),
            _ => Err(SizeError::CouldNotDetermine),
        }
        #[cfg(target_os = "windows")]
        match libpd_sys::libpd_resize_array(name.as_ptr(), size) {
            0 => Ok(()),
            _ => Err(SizeError::CouldNotDetermine),
        }
    }
}

/// Reads a named array from pd to a mutable slice of `f32`.
///
/// Reads values as much as `source_read_amount` from the array which is specified with the `source_name` argument
/// starting from `source_read_offset` and writes them to `destination`.
///
/// # Example
/// ```no_run
/// use libpd_rs::array::read_float_array_from;
///
/// let mut destination = [0.0_f32; 64];
/// read_float_array_from("my_array", 32, 32, &mut destination).unwrap();
/// ```
/// # Errors
/// This function performs no bounds checking on the destination.
///
/// If `destination_offset` + `read_amount` is greater than the size of the `destination` or
/// the array which we're trying to read from is not existent it will return an error.
///
/// A list of errors that can occur:
/// - [`OutOfBounds`](crate::error::ArrayError::OutOfBounds)
/// - [`FailedToFindArray`](crate::error::ArrayError::FailedToFindArray)
pub fn read_float_array_from<T: AsRef<str>>(
    source_name: T,
    source_read_offset: i32,
    source_read_amount: i32,
    destination: &mut [f32],
) -> Result<(), ArrayError> {
    unsafe {
        let name = CString::new(source_name.as_ref()).expect(C_STRING_FAILURE);
        // Returns 0 on success or a negative error code if the array is non-existent
        // or offset + n exceeds range of array

        if source_read_offset + source_read_amount
            > array_size(source_name.as_ref()).map_err(|_| ArrayError::FailedToFindArray)? as i32
            || source_read_amount < 0
        {
            return Err(ArrayError::OutOfBounds);
        }

        match libpd_sys::libpd_read_array(
            destination.as_mut_ptr(),
            name.as_ptr(),
            source_read_offset,
            source_read_amount,
        ) {
            0 => Ok(()),
            _ => Err(ArrayError::FailedToFindArray),
        }
    }
}

/// Writes a slice of `f32` to a pd named array.
///
/// Reads values as much as `read_amount` from the array which is given as the `source` argument
/// and writes them to a named array in pd which is specified with `destination_name` argument starting at `destination_write_offset`.
///
/// # Example
/// ```no_run
/// use libpd_rs::array::write_float_array_to;
///
/// let mut source = [1.0_f32; 64];
/// write_float_array_to("my_array", 32, &source, 32).unwrap();
/// ```
/// # Errors
/// This function performs no bounds checking on the destination.
///
/// If `destination_offset` + `read_amount` is greater than the size of the `destination` or
/// the array which we're trying to read from is not existent it will return an error.
///
/// A list of errors that can occur:
/// - [`OutOfBounds`](crate::error::ArrayError::OutOfBounds)
/// - [`FailedToFindArray`](crate::error::ArrayError::FailedToFindArray)
pub fn write_float_array_to<T: AsRef<str>>(
    destination_name: T,
    destination_write_offset: i32,
    source: &[f32],
    source_read_amount: i32,
) -> Result<(), ArrayError> {
    unsafe {
        let name = CString::new(destination_name.as_ref()).expect(C_STRING_FAILURE);
        // Returns 0 on success or a negative error code if the array is non-existent
        // or offset + n exceeds range of array

        // We check this manually in the predicate.
        #[allow(clippy::cast_sign_loss)]
        if destination_write_offset + source_read_amount
            > array_size(destination_name.as_ref()).map_err(|_| ArrayError::FailedToFindArray)?
                as i32
            || source_read_amount < 0
            || source_read_amount as usize > source.len()
        {
            return Err(ArrayError::OutOfBounds);
        }

        match libpd_sys::libpd_write_array(
            name.as_ptr(),
            destination_write_offset,
            source.as_ptr(),
            source_read_amount,
        ) {
            0 => Ok(()),
            _ => Err(ArrayError::FailedToFindArray),
        }
    }
}

/// Reads a named array from pd to a mutable slice of `f64`.
///
/// Reads values as much as `source_read_amount` from the array which is specified with the `source_name` argument
/// starting from `source_read_offset` and writes them to `destination`.
///
/// # Example
/// ```no_run
/// use libpd_rs::array::read_double_array_from;
///
/// let mut destination = [0.0_f64; 64];
/// read_double_array_from("my_array", 32, 32, &mut destination).unwrap();
/// ```
/// # Errors
/// This function performs no bounds checking on the destination.
///
/// If `destination_offset` + `read_amount` is greater than the size of the `destination` or
/// the array which we're trying to read from is not existent it will return an error.
///
/// A list of errors that can occur:
/// - [`OutOfBounds`](crate::error::ArrayError::OutOfBounds)
/// - [`FailedToFindArray`](crate::error::ArrayError::FailedToFindArray)
pub fn read_double_array_from<T: AsRef<str>>(
    source_name: T,
    source_read_offset: i32,
    source_read_amount: i32,
    destination: &mut [f64],
) -> Result<(), ArrayError> {
    unsafe {
        let name = CString::new(source_name.as_ref()).expect(C_STRING_FAILURE);
        // Returns 0 on success or a negative error code if the array is non-existent
        // or offset + n exceeds range of array

        if source_read_offset + source_read_amount
            > array_size(source_name.as_ref()).map_err(|_| ArrayError::FailedToFindArray)? as i32
            || source_read_amount < 0
        {
            return Err(ArrayError::OutOfBounds);
        }

        match libpd_sys::libpd_read_array_double(
            destination.as_mut_ptr(),
            name.as_ptr(),
            source_read_offset,
            source_read_amount,
        ) {
            0 => Ok(()),
            _ => Err(ArrayError::FailedToFindArray),
        }
    }
}

/// Writes a slice of `f64` to a pd named array.
///
/// Reads values as much as `read_amount` from the array which is given as the `source` argument
/// and writes them to a named array in pd which is specified with `destination_name` argument starting at `destination_write_offset`.
///
/// # Example
/// ```no_run
/// use libpd_rs::array::write_double_array_to;
///
/// let source = [1.0_f64; 64];
/// write_double_array_to("my_array", 32, &source, 32).unwrap();
/// ```
/// # Errors
/// This function performs no bounds checking on the destination.
///
/// If `destination_offset` + `read_amount` is greater than the size of the `destination` or
/// the array which we're trying to read from is not existent it will return an error.
///
/// A list of errors that can occur:
/// - [`OutOfBounds`](crate::error::ArrayError::OutOfBounds)
/// - [`FailedToFindArray`](crate::error::ArrayError::FailedToFindArray)
pub fn write_double_array_to<T: AsRef<str>>(
    destination_name: T,
    destination_write_offset: i32,
    source: &[f64],
    source_read_amount: i32,
) -> Result<(), ArrayError> {
    unsafe {
        let name = CString::new(destination_name.as_ref()).expect(C_STRING_FAILURE);
        // Returns 0 on success or a negative error code if the array is non-existent
        // or offset + n exceeds range of array

        // We check this manually in the predicate.
        #[allow(clippy::cast_sign_loss)]
        if destination_write_offset + source_read_amount
            > array_size(destination_name.as_ref()).map_err(|_| ArrayError::FailedToFindArray)?
                as i32
            || source_read_amount < 0
            || source_read_amount as usize > source.len()
        {
            return Err(ArrayError::OutOfBounds);
        }

        match libpd_sys::libpd_write_array_double(
            name.as_ptr(),
            destination_write_offset,
            source.as_ptr(),
            source_read_amount,
        ) {
            0 => Ok(()),
            _ => Err(ArrayError::FailedToFindArray),
        }
    }
}