rsleigh 0.4.0

use std::ops::Range;

use crate::{
    AttachNumberId, AttachVarnodeId, Number, NumberNonZeroUnsigned, NumberUnsigned, Sleigh, Span,
};

use super::{
    disassembly, BitrangeId, ContextId, InstNext, InstStart, SpaceId, TableId, TokenFieldId,
    UserFunctionId, VarnodeId,
};

#[derive(Clone, Copy, Debug)]
pub enum ExportLen {
    /// value that is known at Dissassembly time
    Const(NumberNonZeroUnsigned),
    /// value that can be know at execution time
    Value(NumberNonZeroUnsigned),
    /// References/registers and other mem locations, all with the same size
    Reference(NumberNonZeroUnsigned),
    /// If each table exports a diferent type, could happen in individual
    /// constructors, if it exports a sub_table that export Multiple
    Multiple(NumberNonZeroUnsigned),
}

impl ExportLen {
    pub fn len(&self) -> NumberNonZeroUnsigned {
        match self {
            Self::Const(len) | Self::Value(len) | Self::Reference(len) | Self::Multiple(len) => {
                *len
            }
        }
    }
}

#[derive(Clone, Debug)]
pub struct Execution {
    pub(crate) variables: Box<[Variable]>,
    pub(crate) blocks: Box<[Block]>,
    pub(crate) export: Option<ExportLen>,

    // TODO make this a const, the first block is always the entry block
    //entry_block have no name and is not on self.labels
    pub entry_block: BlockId,
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
pub struct BlockId(pub usize);

#[derive(Clone, Debug)]
pub struct Block {
    //None is entry block, NOTE name may not be unique due to macro expansions
    pub name: Option<Box<str>>,
    pub next: Option<BlockId>,
    pub statements: Box<[Statement]>,
}

#[derive(Clone, Debug)]
pub enum Statement {
    Delayslot(NumberUnsigned),
    Export(Export),
    CpuBranch(CpuBranch),
    LocalGoto(LocalGoto),
    UserCall(UserCall),
    Build(Build),
    Declare(VariableId),
    Assignment(Assignment),
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, Hash)]
pub struct VariableId(pub usize);

#[derive(Clone, Debug)]
pub struct Variable {
    pub(crate) name: Box<str>,
    pub len_bits: NumberNonZeroUnsigned,
    pub location: Option<Span>,
}

#[derive(Clone, Debug)]
pub enum Expr {
    Value(ExprElement),
    Op(ExprBinaryOp),
}
impl Expr {
    pub fn len_bits(&self, sleigh: &Sleigh, execution: &Execution) -> NumberNonZeroUnsigned {
        match self {
            Expr::Value(value) => value.len_bits(sleigh, execution),
            Expr::Op(op) => op.len_bits,
        }
    }
}

#[derive(Clone, Debug)]
pub struct ExprBinaryOp {
    pub location: Span,
    pub len_bits: NumberNonZeroUnsigned,
    pub op: Binary,
    pub left: Box<Expr>,
    pub right: Box<Expr>,
}

#[derive(Clone, Debug)]
pub enum ExprElement {
    Value { location: Span, value: ExprValue },
    UserCall(UserCall),
    Reference(Reference),
    Op(ExprUnaryOp),
    New(ExprNew),
    CPool(ExprCPool),
}
impl ExprElement {
    fn len_bits(&self, sleigh: &Sleigh, execution: &Execution) -> NumberNonZeroUnsigned {
        match self {
            Self::Value { value, .. } => value.len_bits(sleigh, execution),
            Self::UserCall(_x) => {
                // User functions don't declare return size in SLEIGH;
                // default to address size.
                NumberNonZeroUnsigned::new(sleigh.addr_bytes().get() as u64 * 8).unwrap()
            }
            Self::Reference(x) => x.len_bits,
            Self::Op(x) => x.len_bits(sleigh, execution),
            Self::New(_x) => {
                // ExprNew only appears in JVM/WASM specs — default to 64 bits.
                NumberNonZeroUnsigned::new(64).unwrap()
            }
            Self::CPool(_x) => {
                // ExprCPool only appears in JVM/WASM specs — default to 64 bits.
                NumberNonZeroUnsigned::new(64).unwrap()
            }
        }
    }
}

#[derive(Clone, Debug)]
pub struct Reference {
    pub location: Span,
    pub len_bits: NumberNonZeroUnsigned,
    pub value: ReferencedValue,
}

#[derive(Clone, Debug)]
pub struct ExprUnaryOp {
    pub location: Span,
    pub op: Unary,
    pub input: Box<Expr>,
}

impl ExprUnaryOp {
    pub fn len_bits(&self, sleigh: &Sleigh, execution: &Execution) -> NumberNonZeroUnsigned {
        match &self.op {
            Unary::TakeLsb(len) => (len.get() * 8).try_into().unwrap(),
            Unary::TrunkLsb { trunk: _, bits } => *bits,
            Unary::BitRange { range: _, bits } => *bits,
            Unary::Dereference(mem) => mem.len_bytes,
            Unary::Zext(bits)
            | Unary::Sext(bits)
            | Unary::Popcount(bits)
            | Unary::Lzcount(bits)
            | Unary::FloatNan(bits)
            | Unary::SignTrunc(bits)
            | Unary::Float2Float(bits)
            | Unary::Int2Float(bits) => *bits,
            Unary::Negation
            | Unary::BitNegation
            | Unary::Negative
            | Unary::FloatNegative
            | Unary::FloatAbs
            | Unary::FloatSqrt
            | Unary::FloatCeil
            | Unary::FloatFloor
            | Unary::FloatRound => self.input.len_bits(sleigh, execution),
        }
    }
}

#[derive(Clone, Debug)]
pub struct ExprNew {
    pub location: Span,
    pub first: Box<Expr>,
    pub second: Option<Box<Expr>>,
}

#[derive(Clone, Debug)]
pub struct ExprCPool {
    pub location: Span,
    pub params: Box<[Expr]>,
}

#[derive(Clone, Debug)]
pub struct UserCall {
    pub location: Span,
    pub function: UserFunctionId,
    pub params: Box<[Expr]>,
}

#[derive(Clone, Debug)]
pub enum ExprValue {
    /// Simple Int value
    Int(ExprNumber),
    /// Context/TokenField value translated into a Int
    IntDynamic(ExprDynamicInt),
    InstStart(InstStart),
    InstNext(InstNext),
    /// simple TokenField, no attachment
    TokenField(ExprTokenField),
    /// simple Context, no attachment
    Context(ExprContext),
    /// A Varnode Value
    Varnode(VarnodeId),
    /// A Context/TokenField translated into a varnode
    VarnodeDynamic(ExprVarnodeDynamic),
    /// Dynamic Int from Context or TokenField
    Bitrange(ExprBitrange),
    Table(TableId),
    DisVar(ExprDisVar),
    ExeVar(VariableId),
}

impl ExprValue {
    pub fn len_bits(&self, sleigh: &Sleigh, execution: &Execution) -> NumberNonZeroUnsigned {
        match self {
            Self::Int(x) => x.size,
            Self::TokenField(x) => x.size,
            Self::InstStart(_) | Self::InstNext(_) => {
                (sleigh.addr_bytes().get() * 8).try_into().unwrap()
            }
            Self::Varnode(x) => (sleigh.varnode(*x).len_bytes.get() * 8).try_into().unwrap(),
            Self::Context(x) => sleigh.context(x.id).bitrange.bits.len(),
            Self::Bitrange(x) => sleigh.bitrange(x.id).bits.len(),
            Self::Table(x) => sleigh.table(*x).export.unwrap().len(),
            Self::DisVar(x) => x.size,
            Self::ExeVar(x) => execution.variable(*x).len_bits,
            Self::IntDynamic(ExprDynamicInt { bits, .. }) => *bits,
            Self::VarnodeDynamic(ExprVarnodeDynamic { attach_id, .. }) => {
                sleigh.attach_varnode(*attach_id).len_bytes(sleigh)
            }
        }
    }
}

#[derive(Clone, Debug)]
pub struct ExprNumber {
    pub size: NumberNonZeroUnsigned,
    pub number: Number,
}

#[derive(Clone, Debug)]
pub struct ExprDynamicInt {
    pub attach_id: AttachNumberId,
    pub attach_value: DynamicValueType,
    pub bits: NumberNonZeroUnsigned,
}

#[derive(Clone, Debug)]
pub struct ExprVarnodeDynamic {
    pub attach_id: AttachVarnodeId,
    pub attach_value: DynamicValueType,
}

#[derive(Clone, Debug)]
pub struct ExprTokenField {
    pub size: NumberNonZeroUnsigned,
    pub id: TokenFieldId,
}

#[derive(Clone, Debug)]
pub enum ExprVarnode {
    Static(VarnodeId),
    Dynamic {
        attach_id: AttachVarnodeId,
        attach_value: DynamicValueType,
    },
}

/// Only used for types with attachment values to Varnodes/Ints
#[derive(Copy, Clone, Debug)]
pub enum DynamicValueType {
    TokenField(TokenFieldId),
    Context(ContextId),
}

#[derive(Clone, Debug)]
pub struct ExprContext {
    pub size: NumberNonZeroUnsigned,
    pub id: ContextId,
}

#[derive(Clone, Debug)]
pub struct ExprBitrange {
    pub size: NumberNonZeroUnsigned,
    pub id: BitrangeId,
}

#[derive(Clone, Debug)]
pub struct ExprDisVar {
    pub size: NumberNonZeroUnsigned,
    pub id: disassembly::VariableId,
}

#[derive(Clone, Debug)]
pub enum ReferencedValue {
    //only if translate into varnode
    TokenField(RefTokenField),
    InstStart(RefInstStart),
    InstNext(RefInstNext),
    Table(RefTable),
}

#[derive(Clone, Debug)]
pub struct RefTokenField {
    pub location: Span,
    pub id: TokenFieldId,
}

#[derive(Clone, Debug)]
pub struct RefInstStart {
    pub location: Span,
    pub data: InstStart,
}

#[derive(Clone, Debug)]
pub struct RefInstNext {
    pub location: Span,
    pub data: InstNext,
}

#[derive(Clone, Debug)]
pub struct RefTable {
    pub location: Span,
    pub id: TableId,
}

#[derive(Clone, Debug)]
pub struct CpuBranch {
    pub cond: Option<Expr>,
    pub call: BranchCall,
    pub direct: bool,
    pub dst: Expr,
}

#[derive(Clone, Debug, Copy)]
pub enum BranchCall {
    Goto,
    Call,
    Return,
}

#[derive(Clone, Debug)]
pub struct LocalGoto {
    pub cond: Option<Expr>,
    pub dst: BlockId,
}

#[derive(Clone, Debug)]
pub struct Assignment {
    /// assigment location
    pub location: Span,
    /// left side of the assignment location
    pub var: AssignmentWrite,
    pub right: Expr,
}

#[derive(Clone, Debug)]
pub enum AssignmentWrite {
    Variable {
        value: AssignmentWriteVariable,
        op: Option<AssignmentOp>,
    },
    Memory {
        mem: MemoryLocation,
        addr: Expr,
    },
    // write to memory based on the table export
    TableExport {
        table_id: TableId,
        op: Option<AssignmentOp>,
        // number of bytes to write in case of memory reference
        size: Option<NumberNonZeroUnsigned>,
    },
}

#[derive(Clone, Debug)]
pub enum AssignmentWriteVariable {
    Varnode(VarnodeId),
    Bitrange(BitrangeId),
    DynVarnode {
        value_id: DynamicValueType,
        attach_id: AttachVarnodeId,
    },
    Variable(VariableId),
}

#[derive(Clone, Debug)]
pub enum AssignmentOp {
    TakeLsb(NumberNonZeroUnsigned),
    TrunkLsb(NumberUnsigned),
    BitRange(Range<NumberUnsigned>),
}

#[derive(Clone, Debug)]
pub struct Build {
    pub location: Span,
    pub table: TableId,
}

#[derive(Clone, Debug)]
pub enum Export {
    /// Reference to a memory
    /// NOTE not the same as deref a memory address
    /// a regular Expr Deref exports the result on a deref.
    /// a Export Deref export the location itself, and read/write is done a demand
    Reference { addr: Expr, memory: MemoryLocation },
    /// a value that translate into a varnode (AKA reference with extra steps)
    AttachVarnode {
        location: Span,
        attach_value: DynamicValueType,
        attach_id: AttachVarnodeId,
    },
    /// a subtable re-exported
    Table { location: Span, table_id: TableId },

    /// other complex expressions
    Value(Expr),
}

impl Export {
    pub fn len_bits(&self, sleigh: &Sleigh, execution: &Execution) -> NumberNonZeroUnsigned {
        match self {
            Export::Value(value) => value.len_bits(sleigh, execution),
            Export::Reference { addr: _, memory } => {
                (memory.len_bytes.get() * 8).try_into().unwrap()
            }
            Export::AttachVarnode { attach_id, .. } => {
                (sleigh.attach_varnodes_len_bytes(*attach_id).get() * 8)
                    .try_into()
                    .unwrap()
            }
            Export::Table { table_id, .. } => {
                let table = sleigh.table(*table_id);
                table.export.unwrap().len()
            }
        }
    }
}

#[derive(Clone, Debug)]
pub struct MemoryLocation {
    pub location: Span,
    pub space: SpaceId,
    pub len_bytes: NumberNonZeroUnsigned,
}

#[derive(Clone, Debug)]
pub enum Unary {
    TakeLsb(NumberNonZeroUnsigned),
    TrunkLsb {
        trunk: NumberUnsigned,
        bits: NumberNonZeroUnsigned,
    },
    // BitRange have an auto Sext to it
    BitRange {
        range: Range<NumberUnsigned>,
        bits: NumberNonZeroUnsigned,
    },
    Dereference(MemoryLocation),
    //Reference(AddrReference),
    Zext(NumberNonZeroUnsigned),
    Sext(NumberNonZeroUnsigned),
    Popcount(NumberNonZeroUnsigned),
    Lzcount(NumberNonZeroUnsigned),
    FloatNan(NumberNonZeroUnsigned),
    /// NOTE don't confuse signed truncation with regular truncation
    /// sleigh `trunc` function converts float into interger
    SignTrunc(NumberNonZeroUnsigned),
    Float2Float(NumberNonZeroUnsigned),
    Int2Float(NumberNonZeroUnsigned),

    /// output size is just the input size
    Negation,
    BitNegation,
    Negative,
    FloatNegative,
    FloatAbs,
    FloatSqrt,
    FloatCeil,
    FloatFloor,
    FloatRound,
}

#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum Binary {
    //Binary Arithmetic
    Mult,
    Div,
    SigDiv,
    Rem,
    FloatDiv,
    FloatMult,
    Add,
    Sub,
    FloatAdd,
    FloatSub,
    Lsl,
    Lsr,
    Asr,
    BitAnd,
    BitXor,
    BitOr,
    //Binary Logical
    SigLess,
    SigGreater,
    SigRem,
    SigLessEq,
    SigGreaterEq,
    Less,
    Greater,
    LessEq,
    GreaterEq,
    FloatLess,
    FloatGreater,
    FloatLessEq,
    FloatGreaterEq,
    And,
    Xor,
    Or,
    Eq,
    Ne,
    FloatEq,
    FloatNe,
    //call functions
    Carry,
    SCarry,
    SBorrow,
}

impl Variable {
    pub fn name(&self) -> &str {
        &self.name
    }
}

impl Execution {
    pub fn variables(&self) -> &[Variable] {
        &self.variables
    }

    pub fn blocks(&self) -> &[Block] {
        &self.blocks
    }

    pub fn block(&self, id: BlockId) -> &Block {
        &self.blocks[id.0]
    }

    pub fn export_len(&self) -> Option<ExportLen> {
        self.export
    }

    pub fn export(&self) -> impl Iterator<Item = &Export> {
        self.blocks.iter().filter_map(|block| {
            block
                .statements
                .last()
                .and_then(|statement| match statement {
                    Statement::Export(export) => Some(export),
                    _ => None,
                })
        })
    }

    pub fn variable(&self, var: VariableId) -> &Variable {
        &self.variables[var.0]
    }
}