#ifndef LPYTHON_SEMANTICS_COMPTIME_EVAL_H

#define LPYTHON_SEMANTICS_COMPTIME_EVAL_H

#include <complex>

#include <string>

#include <cstring>

#include <cmath>

#include <sstream>

#include <algorithm>

#include <iterator>

#include <libasr/asr.h>

#include <lpython/ast.h>

#include <lpython/bigint.h>

#include <libasr/string_utils.h>

#include <lpython/utils.h>

#include <lpython/semantics/semantic_exception.h>

namespace LFortran {

struct PythonIntrinsicProcedures {

const std::string m_builtin = "lpython_builtin";

typedef ASR::expr_t* (*comptime_eval_callback)(Allocator &, const Location &, Vec<ASR::expr_t*> &);

// Table of intrinsics

// The callback is only called if all arguments have compile time `value`

// which is always one of the `Constant*` expression ASR nodes, so inside

// the callback one can assume that.

std::map<std::string, std::tuple<std::string, comptime_eval_callback>> comptime_eval_map;

PythonIntrinsicProcedures() {

comptime_eval_map = {

{"abs", {m_builtin, &eval_abs}},

{"str", {m_builtin, &eval_str}},

{"bool", {m_builtin, &eval_bool}},

{"chr", {m_builtin, &eval_chr}},

{"ord", {m_builtin, &eval_ord}},

{"len", {m_builtin, &eval_len}},

{"pow", {m_builtin, &eval_pow}},

{"int", {m_builtin, &eval_int}},

{"float", {m_builtin, &eval_float}},

{"bin", {m_builtin, &eval_bin}},

{"hex", {m_builtin, &eval_hex}},

{"oct", {m_builtin, &eval_oct}},

};

}

// Return `true` if `name` is in the table of intrinsics

bool is_intrinsic(std::string name) const {

auto search = comptime_eval_map.find(name);

if (search != comptime_eval_map.end()) {

return true;

} else {

return false;

}

}

// Looks up `name` in the table of intrinsics and returns the corresponding

// module name; Otherwise rises an exception

std::string get_module(std::string name, const Location &loc) const {

auto search = comptime_eval_map.find(name);

if (search != comptime_eval_map.end()) {

std::string module_name = std::get<0>(search->second);

return module_name;

} else {

throw SemanticError("Function '" + name

+ "' not found among intrinsic procedures",

loc);

}

}

// Evaluates the intrinsic function `name` at compile time

ASR::expr_t *comptime_eval(std::string name, Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) const {

auto search = comptime_eval_map.find(name);

if (search != comptime_eval_map.end()) {

comptime_eval_callback cb = std::get<1>(search->second);

Vec<ASR::expr_t*> arg_values = ASRUtils::get_arg_values(al, args);

if (arg_values.size() != args.size()) {

// Not all arguments have compile time values; we do not call the callback

return nullptr;

}

return cb(al, loc, arg_values);

} else {

throw SemanticError("Intrinsic function '" + name

+ "' compile time evaluation is not implemented yet",

loc);

}

}

static ASR::expr_t *eval_abs(Allocator &al, const Location &loc,

Vec<ASR::expr_t*> &args

) {

LFORTRAN_ASSERT(ASRUtils::all_args_evaluated(args));

if (args.size() != 1) {

throw SemanticError("Intrinsic abs function accepts exactly 1 argument", loc);

}

ASR::expr_t* trig_arg = args[0];

ASR::ttype_t* t = ASRUtils::expr_type(args[0]);

if (ASR::is_a<ASR::Real_t>(*t)) {

double rv = ASR::down_cast<ASR::ConstantReal_t>(trig_arg)->m_r;

double val = std::abs(rv);

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantReal_t(al, loc, val, t));

} else if (ASR::is_a<ASR::Integer_t>(*t)) {

int64_t rv = ASR::down_cast<ASR::ConstantInteger_t>(trig_arg)->m_n;

int64_t val = std::abs(rv);

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantInteger_t(al, loc, val, t));

} else if (ASR::is_a<ASR::Complex_t>(*t)) {

double re = ASR::down_cast<ASR::ConstantComplex_t>(trig_arg)->m_re;

double im = ASR::down_cast<ASR::ConstantComplex_t>(trig_arg)->m_im;

std::complex<double> x(re, im);

double result = std::abs(x);

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantReal_t(al, loc, result, t));

} else {

throw SemanticError("Argument of the abs function must be Integer, Real or Complex", loc);

}

}

static ASR::expr_t *eval_str(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

ASR::ttype_t* str_type = ASRUtils::TYPE(ASR::make_Character_t(al,

loc, 1, 1, nullptr, nullptr, 0));

if (args.size() == 0) { // create an empty string

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantString_t(al, loc, s2c(al, ""), str_type));

}

ASR::expr_t* arg = ASRUtils::expr_value(args[0]);

ASR::ttype_t* arg_type = ASRUtils::expr_type(arg);

if (ASRUtils::is_integer(*arg_type)) {

int64_t ival = ASR::down_cast<ASR::ConstantInteger_t>(arg)->m_n;

std::string s = std::to_string(ival);

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantString_t(al, loc, s2c(al, s), str_type));

} else if (ASRUtils::is_real(*arg_type)) {

double rval = ASR::down_cast<ASR::ConstantReal_t>(arg)->m_r;

std::string s = std::to_string(rval);

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantString_t(al, loc, s2c(al, s), str_type));

} else if (ASRUtils::is_logical(*arg_type)) {

bool rv = ASR::down_cast<ASR::ConstantLogical_t>(arg)->m_value;

std::string s = rv ? "True" : "False";

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantString_t(al, loc, s2c(al, s), str_type));

} else if (ASRUtils::is_character(*arg_type)) {

char* c = ASR::down_cast<ASR::ConstantString_t>(arg)->m_s;

std::string s = std::string(c);

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantString_t(al, loc, s2c(al, s), str_type));

} else {

throw SemanticError("str() argument must be real, integer, logical, or a string, not '" +

ASRUtils::type_to_str(arg_type) + "'", loc);

}

}

static ASR::expr_t *eval_bool(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

if (args.size() != 1) {

throw SemanticError("bool() takes exactly one argument (" +

std::to_string(args.size()) + " given)", loc);

}

ASR::ttype_t *type = ASRUtils::TYPE(ASR::make_Logical_t(al, loc,

1, nullptr, 0));

ASR::expr_t* arg = ASRUtils::expr_value(args[0]);

ASR::ttype_t* t = ASRUtils::expr_type(arg);

bool result;

if (ASRUtils::is_real(*t)) {

double rv = ASR::down_cast<ASR::ConstantReal_t>(arg)->m_r;

result = rv ? true : false;

} else if (ASRUtils::is_integer(*t)) {

int64_t rv = ASR::down_cast<ASR::ConstantInteger_t>(arg)->m_n;

result = rv ? true : false;

} else if (ASRUtils::is_complex(*t)) {

double re = ASR::down_cast<ASR::ConstantComplex_t>(arg)->m_re;

double im = ASR::down_cast<ASR::ConstantComplex_t>(arg)->m_im;

std::complex<double> c(re, im);

result = (re || im) ? true : false;

} else if (ASRUtils::is_logical(*t)) {

bool rv = ASR::down_cast<ASR::ConstantLogical_t>(arg)->m_value;

result = rv;

} else if (ASRUtils::is_character(*t)) {

char* c = ASR::down_cast<ASR::ConstantString_t>(ASRUtils::expr_value(arg))->m_s;

result = strlen(s2c(al, std::string(c))) ? true : false;

} else {

throw SemanticError("bool() must have one real, integer, character,"

" complex, or logical argument, not '" + ASRUtils::type_to_str(t) + "'", loc);

}

return ASR::down_cast<ASR::expr_t>(make_ConstantLogical_t(al, loc, result, type));

}

static ASR::expr_t *eval_chr(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

LFORTRAN_ASSERT(ASRUtils::all_args_evaluated(args));

ASR::expr_t* arg = args[0];

ASR::ttype_t* type = ASRUtils::expr_type(arg);

if (ASR::is_a<ASR::Integer_t>(*type)) {

int64_t c = ASR::down_cast<ASR::ConstantInteger_t>(arg)->m_n;

ASR::ttype_t* str_type =

ASRUtils::TYPE(ASR::make_Character_t(al,

loc, 1, 1, nullptr, nullptr, 0));

if (! (c >= 0 && c <= 127) ) {

throw SemanticError("The argument 'x' in chr(x) must be in the range 0 <= x <= 127.", loc);

}

char cc = c;

std::string svalue;

svalue += cc;

return ASR::down_cast<ASR::expr_t>(

ASR::make_ConstantString_t(al, loc, s2c(al, svalue), str_type));

} else {

throw SemanticError("chr() must have one integer argument.", loc);

}

}

static ASR::expr_t *eval_ord(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

LFORTRAN_ASSERT(ASRUtils::all_args_evaluated(args));

ASR::expr_t* char_expr = args[0];

ASR::ttype_t* char_type = ASRUtils::expr_type(char_expr);

if (ASRUtils::is_character(*char_type)) {

char* c = ASR::down_cast<ASR::ConstantString_t>(ASRUtils::expr_value(char_expr))->m_s;

ASR::ttype_t* int_type =

ASRUtils::TYPE(ASR::make_Integer_t(al, loc, 4, nullptr, 0));

return ASR::down_cast<ASR::expr_t>(

ASR::make_ConstantInteger_t(al, loc, c[0], int_type));

} else {

throw SemanticError("ord() must have one character argument", loc);

}

}

static ASR::expr_t *eval_len(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

if (args.size() != 1) {

throw SemanticError("len() takes exactly one argument (" +

std::to_string(args.size()) + " given)", loc);

}

ASR::expr_t *arg = ASRUtils::expr_value(args[0]);

ASR::ttype_t *type = ASRUtils::TYPE(ASR::make_Integer_t(al, loc, 4, nullptr, 0));

if (arg->type == ASR::exprType::ConstantString) {

char* str_value = ASR::down_cast<ASR::ConstantString_t>(arg)->m_s;

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc,

(int64_t)strlen(s2c(al, std::string(str_value))), type));

} else if (arg->type == ASR::exprType::ConstantArray) {

return ASR::down_cast<ASR::expr_t>(ASR::make_ConstantInteger_t(al, loc,

(int64_t)ASR::down_cast<ASR::ConstantArray_t>(arg)->n_args, type));

} else if (arg->type == ASR::exprType::ConstantTuple) {

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc,

(int64_t)ASR::down_cast<ASR::ConstantTuple_t>(arg)->n_elements, type));

} else if (arg->type == ASR::exprType::ConstantDictionary) {

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc,

(int64_t)ASR::down_cast<ASR::ConstantDictionary_t>(arg)->n_keys, type));

} else if (arg->type == ASR::exprType::ConstantSet) {

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc,

(int64_t)ASR::down_cast<ASR::ConstantSet_t>(arg)->n_elements, type));

} else {

throw SemanticError("len() only works on strings, lists, tuples, dictionaries and sets",

loc);

}

}

static ASR::expr_t *eval_pow(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

LFORTRAN_ASSERT(ASRUtils::all_args_evaluated(args));

ASR::expr_t* arg1 = ASRUtils::expr_value(args[0]);

ASR::expr_t* arg2 = ASRUtils::expr_value(args[1]);

ASR::ttype_t* arg1_type = ASRUtils::expr_type(arg1);

ASR::ttype_t* arg2_type = ASRUtils::expr_type(arg2);

ASR::ttype_t *int_type = ASRUtils::TYPE(ASR::make_Integer_t(al, loc, 4, nullptr, 0));

ASR::ttype_t *real_type = ASRUtils::TYPE(ASR::make_Real_t(al, loc, 8, nullptr, 0));

if (!ASRUtils::check_equal_type(arg1_type, arg2_type)) {

throw SemanticError("The arguments to pow() must have the same type.", loc);

}

if (ASRUtils::is_integer(*arg1_type) && ASRUtils::is_integer(*arg2_type)) {

int64_t a = ASR::down_cast<ASR::ConstantInteger_t>(arg1)->m_n;

int64_t b = ASR::down_cast<ASR::ConstantInteger_t>(arg2)->m_n;

if (a == 0 && b < 0) { // Zero Division

throw SemanticError("0.0 cannot be raised to a negative power.", loc);

}

if (b < 0) // Negative power

return ASR::down_cast<ASR::expr_t>(make_ConstantReal_t(al, loc,

pow(a, b), real_type));

else // Positive power

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc,

(int64_t)pow(a, b), int_type));

} else {

throw SemanticError("The arguments to pow() must be of type integers for now.", loc);

}

}

static ASR::expr_t *eval_int(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

ASR::ttype_t *type = ASRUtils::TYPE(ASR::make_Integer_t(al, loc, 4, nullptr, 0));

if (args.size() == 0) {

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc, 0, type));

}

ASR::expr_t* int_expr = ASRUtils::expr_value(args[0]);

ASR::ttype_t* int_type = ASRUtils::expr_type(int_expr);

if (ASRUtils::is_integer(*int_type)) {

int64_t ival = ASR::down_cast<ASR::ConstantInteger_t>(int_expr)->m_n;

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc, ival, type));

} else if (ASRUtils::is_character(*int_type)) {

// convert a string to an int

char* c = ASR::down_cast<ASR::ConstantString_t>(int_expr)->m_s;

std::string str = std::string(c);

int64_t ival = std::stoll(str);

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc, ival, type));

} else if (ASRUtils::is_real(*int_type)) {

int64_t ival = ASR::down_cast<ASR::ConstantReal_t>(int_expr)->m_r;

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc, ival, type));

} else if (ASRUtils::is_logical(*int_type)) {

bool rv = ASR::down_cast<ASR::ConstantLogical_t>(int_expr)->m_value;

int8_t val = rv ? 1 : 0;

return ASR::down_cast<ASR::expr_t>(make_ConstantInteger_t(al, loc, val, type));

} else {

throw SemanticError("int() argument must be real, integer, logical, or a string, not '" +

ASRUtils::type_to_str(int_type) + "'", loc);

}

}

static ASR::expr_t *eval_float(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

ASR::ttype_t* type = ASRUtils::TYPE(ASR::make_Real_t(al, loc, 8, nullptr, 0));

if (args.size() == 0) {

return ASR::down_cast<ASR::expr_t>(make_ConstantReal_t(al, loc, 0.0, type));

}

ASR::expr_t* expr = ASRUtils::expr_value(args[0]);

ASR::ttype_t* float_type = ASRUtils::expr_type(expr);

if (ASRUtils::is_real(*float_type)) {

float rv = ASR::down_cast<ASR::ConstantReal_t>(expr)->m_r;

return ASR::down_cast<ASR::expr_t>(make_ConstantReal_t(al, loc, rv, type));

} else if (ASRUtils::is_integer(*float_type)) {

double rv = ASR::down_cast<ASR::ConstantInteger_t>(expr)->m_n;

return ASR::down_cast<ASR::expr_t>(make_ConstantReal_t(al, loc, rv, type));

} else if (ASRUtils::is_logical(*float_type)) {

bool rv = ASR::down_cast<ASR::ConstantLogical_t>(expr)->m_value;

float val = rv ? 1.0 : 0.0;

return ASR::down_cast<ASR::expr_t>(make_ConstantReal_t(al, loc, val, type));

} else if (ASRUtils::is_character(*float_type)) {

// convert a string to a float

char* c = ASR::down_cast<ASR::ConstantString_t>(expr)->m_s;

std::string str = std::string(c);

float rv = std::stof(str);

return ASR::down_cast<ASR::expr_t>(make_ConstantReal_t(al, loc, rv, type));

} else {

throw SemanticError("float() argument must be real, integer, logical, or a string, not '" +

ASRUtils::type_to_str(float_type) + "'", loc);

}

}

static ASR::expr_t *eval_bin(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

if (args.size() != 1) {

throw SemanticError("bin() takes exactly one argument (" +

std::to_string(args.size()) + " given)", loc);

}

ASR::expr_t* expr = ASRUtils::expr_value(args[0]);

ASR::ttype_t* type = ASRUtils::expr_type(expr);

if (ASRUtils::is_integer(*type)) {

int64_t n = ASR::down_cast<ASR::ConstantInteger_t>(expr)->m_n;

ASR::ttype_t* str_type = ASRUtils::TYPE(ASR::make_Character_t(al,

loc, 1, 1, nullptr, nullptr, 0));

std::string str, prefix;

prefix = n > 0 ? "0b" : "-0b";

str += std::bitset<64>(std::abs(n)).to_string();

str.erase(0, str.find_first_not_of('0'));

str.insert(0, prefix);

return ASR::down_cast<ASR::expr_t>(make_ConstantString_t(al, loc, s2c(al, str), str_type));

} else {

throw SemanticError("bin() argument must be an integer, not '" +

ASRUtils::type_to_str(type) + "'", loc);

}

}

static ASR::expr_t *eval_hex(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

if (args.size() != 1) {

throw SemanticError("hex() takes exactly one argument (" +

std::to_string(args.size()) + " given)", loc);

}

ASR::expr_t* expr = ASRUtils::expr_value(args[0]);

ASR::ttype_t* type = ASRUtils::expr_type(expr);

if (ASRUtils::is_integer(*type)) {

int64_t n = ASR::down_cast<ASR::ConstantInteger_t>(expr)->m_n;

ASR::ttype_t* str_type = ASRUtils::TYPE(ASR::make_Character_t(al,

loc, 1, 1, nullptr, nullptr, 0));

std::string str, prefix;

std::stringstream ss;

prefix = n > 0 ? "0x" : "-0x";

ss << std::hex << std::abs(n);

str += ss.str();

str.insert(0, prefix);

return ASR::down_cast<ASR::expr_t>(make_ConstantString_t(al, loc, s2c(al, str), str_type));

} else {

throw SemanticError("hex() argument must be an integer, not '" +

ASRUtils::type_to_str(type) + "'", loc);

}

}

static ASR::expr_t *eval_oct(Allocator &al, const Location &loc, Vec<ASR::expr_t*> &args) {

if (args.size() != 1) {

throw SemanticError("oct() takes exactly one argument (" +

std::to_string(args.size()) + " given)", loc);

}

ASR::expr_t* expr = ASRUtils::expr_value(args[0]);

ASR::ttype_t* type = ASRUtils::expr_type(expr);

if (ASRUtils::is_integer(*type)) {

int64_t n = ASR::down_cast<ASR::ConstantInteger_t>(expr)->m_n;

ASR::ttype_t* str_type = ASRUtils::TYPE(ASR::make_Character_t(al,

loc, 1, 1, nullptr, nullptr, 0));

std::string str, prefix;

std::stringstream ss;

prefix = n > 0 ? "0o" : "-0o";

ss << std::oct << std::abs(n);

str += ss.str();

str.insert(0, prefix);

return ASR::down_cast<ASR::expr_t>(make_ConstantString_t(al, loc, s2c(al, str), str_type));

} else {

throw SemanticError("oct() argument must be an integer, not '" +

ASRUtils::type_to_str(type) + "'", loc);

}

}

}; // ComptimeEval

} // namespace LFortran

#endif /* LPYTHON_SEMANTICS_COMPTIME_EVAL_H */