use std::ops::Range;

use crate::architecture::Architecture;
use crate::basicblock::{BasicBlock, BlockContext};

use super::*;

pub struct BlockIter<'func, A, M, F>
where
    A: 'func + Architecture,
    M: FunctionMutability,
    F: FunctionForm,
{
    function: &'func Function<A, M, F>,
    range: Range<u64>,
}

impl<'func, A, M, F> Iterator for BlockIter<'func, A, M, F>
where
    A: 'func + Architecture,
    M: FunctionMutability,
    F: FunctionForm,
{
    type Item = Instruction<'func, A, M, F>;

    fn next(&mut self) -> Option<Self::Item> {
        self.range.next().map(|i| Instruction {
            function: self.function,
            instr_idx: i as usize,
        })
    }
}



pub struct Block<'func, A, M, F>
where
    A: 'func + Architecture,
    M: FunctionMutability,
    F: FunctionForm,
{
    pub(crate) function: &'func Function<A, M, F>,
}

impl<'func, A, M, F> fmt::Debug for Block<'func, A, M, F>
where
    A: 'func + Architecture,
    M: FunctionMutability,
    F: FunctionForm,
{
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "llil_bb {:?}", self.function)
    }
}

impl<'func, A, M, F> BlockContext for Block<'func, A, M, F>
where
    A: 'func + Architecture,
    M: FunctionMutability,
    F: FunctionForm,
{
    type Iter = BlockIter<'func, A, M, F>;
    type Instruction = Instruction<'func, A, M, F>;

    fn start(&self, block: &BasicBlock<Self>) -> Instruction<'func, A, M, F> {
        Instruction {
            function: self.function,
            instr_idx: block.raw_start() as usize,
        }
    }

    fn iter(&self, block: &BasicBlock<Self>) -> BlockIter<'func, A, M, F> {
        BlockIter {
            function: self.function,
            range: block.raw_start() .. block.raw_end(),
        }
    }
}

impl<'func, A, M, F> Clone for Block<'func, A, M, F>
where
    A: 'func + Architecture,
    M: FunctionMutability,
    F: FunctionForm,
{
    fn clone(&self) -> Self {
        Block { function: self.function }
    }
}