use super::*;

// here may be a interesting part for lab
pub trait MemoryHandler: Debug + Send + Sync + 'static {
    fn box_clone(&self) -> Box<MemoryHandler>;

    /// Map `addr` in the page table
    /// Should set page flags here instead of in page_fault_handler
    fn map(&self, pt: &mut PageTable, addr: VirtAddr, attr: &MemoryAttr);

    /// Unmap `addr` in the page table
    fn unmap(&self, pt: &mut PageTable, addr: VirtAddr);

    /// Clone map `addr` from one page table to another.
    /// `pt` is the current active page table.
    /// `with` is the `InactivePageTable::with` function.
    /// Call `with` then use `pt` as target page table inside.
    fn clone_map(
        &self,
        pt: &mut PageTable,
        with: &Fn(&mut FnMut()),
        addr: VirtAddr,
        attr: &MemoryAttr,
    );

    /// Handle page fault on `addr`
    /// Return true if success, false if error
    fn handle_page_fault(&self, pt: &mut PageTable, addr: VirtAddr) -> bool;
}

impl Clone for Box<MemoryHandler> {
    fn clone(&self) -> Box<MemoryHandler> {
        self.box_clone()
    }
}

pub trait FrameAllocator: Debug + Clone + Send + Sync + 'static {
    fn alloc(&self) -> Option<PhysAddr>;
    fn dealloc(&self, target: PhysAddr);
}

mod byframe;
mod delay;
mod linear;
mod file;
//mod swap;

pub use self::byframe::ByFrame;
pub use self::delay::Delay;
pub use self::linear::Linear;
pub use self::file::{File, Read};