use crate::constants_table::ConstantsTable;
use crate::ir::assemble::{Assemble, InstructionsBuilder};
use crate::ir::ir_assign::IrAssign;
use crate::ir::ir_call::IrCall;
use crate::ir::ir_return::IrReturn;
use crate::ir::ir_variable::IrVrVariableDescriptor;
use crate::ir::register_allocation::{OffsetCounter, VrUser};
use std::collections::{HashMap, HashSet};
use std::fmt::{Display, Formatter};

pub enum IrStatement {
    Assign(IrAssign),
    Call(IrCall),
    Return(IrReturn),
}

impl VrUser for IrStatement {
    fn vr_definitions(&self) -> HashSet<IrVrVariableDescriptor> {
        match self {
            IrStatement::Assign(ir_assign) => ir_assign.vr_definitions(),
            IrStatement::Call(ir_call) => ir_call.vr_definitions(),
            IrStatement::Return(ir_return) => ir_return.vr_definitions(),
        }
    }

    fn vr_uses(&self) -> HashSet<IrVrVariableDescriptor> {
        match self {
            IrStatement::Assign(ir_assign) => ir_assign.vr_uses(),
            IrStatement::Call(ir_call) => ir_call.vr_uses(),
            IrStatement::Return(ir_return) => ir_return.vr_uses(),
        }
    }

    fn propagate_spills(&mut self, spills: &HashSet<IrVrVariableDescriptor>) {
        match self {
            IrStatement::Assign(ir_assign) => {
                ir_assign.propagate_spills(spills);
            }
            IrStatement::Call(ir_call) => {
                ir_call.propagate_spills(spills);
            }
            IrStatement::Return(ir_return) => {
                ir_return.propagate_spills(spills);
            }
        }
    }

    fn propagate_register_assignments(
        &mut self,
        assignments: &HashMap<IrVrVariableDescriptor, usize>,
    ) {
        match self {
            IrStatement::Assign(ir_assign) => {
                ir_assign.propagate_register_assignments(assignments);
            }
            IrStatement::Call(ir_call) => {
                ir_call.propagate_register_assignments(assignments);
            }
            IrStatement::Return(ir_return) => {
                ir_return.propagate_register_assignments(assignments);
            }
        }
    }

    fn propagate_stack_offsets(&mut self, counter: &mut OffsetCounter) {
        match self {
            IrStatement::Assign(ir_assign) => {
                ir_assign.propagate_stack_offsets(counter);
            }
            IrStatement::Call(ir_call) => {
                ir_call.propagate_stack_offsets(counter);
            }
            IrStatement::Return(ir_return) => {
                ir_return.propagate_stack_offsets(counter);
            }
        }
    }
}

impl Assemble for IrStatement {
    fn assemble(&self, builder: &mut InstructionsBuilder, constants_table: &mut ConstantsTable) {
        match self {
            IrStatement::Assign(ir_assign) => {
                ir_assign.assemble(builder, constants_table);
            }
            IrStatement::Call(ir_call) => {
                ir_call.assemble(builder, constants_table);
            }
            IrStatement::Return(ir_return) => {
                ir_return.assemble(builder, constants_table);
            }
        }
    }
}

impl Display for IrStatement {
    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
        match self {
            IrStatement::Assign(ir_assign) => {
                write!(f, "{}", ir_assign)
            }
            IrStatement::Call(ir_call) => {
                write!(f, "{}", ir_call)
            }
            IrStatement::Return(ir_return) => {
                write!(f, "{}", ir_return)
            }
        }
    }
}