/*
Copyright (c) 2013 Microsoft Corporation. All rights reserved.
Released under Apache 2.0 license as described in the file LICENSE.

Author: Leonardo de Moura
*/
#include "lean_operator_info.h"
#include "rc.h"

namespace lean {
/** \brief Actual implementation of operator_info */
struct operator_info::imp {
    void dealloc() { delete this;  }
    MK_LEAN_RC();
    fixity        m_fixity;
    unsigned      m_precedence;
    list<name>    m_op_parts;  // operator parts, > 1 only if the operator is mixfix.
    list<expr>    m_exprs;     // possible interpretations for the operator.

    imp(name const & op, fixity f, unsigned p):
        m_rc(1), m_fixity(f), m_precedence(p), m_op_parts(cons(op, list<name>())) {}

    imp(unsigned num_parts, name const * parts, fixity f, unsigned p):
        m_rc(1), m_fixity(f), m_precedence(p), m_op_parts(copy_to_list<name const *, name>(parts, parts + num_parts)) {
        lean_assert(num_parts > 0);
    }

    imp(imp const & s):
        m_rc(1), m_fixity(s.m_fixity), m_precedence(s.m_precedence), m_op_parts(s.m_op_parts), m_exprs(s.m_exprs) {
    }

    bool is_eq(imp const & other) const {
        return
            m_fixity == other.m_fixity &&
            m_precedence == other.m_precedence &&
            m_op_parts == other.m_op_parts;
    }

};

operator_info::operator_info(imp * p):m_ptr(p) {}

operator_info::operator_info(operator_info const & info):m_ptr(info.m_ptr) { if (m_ptr) m_ptr->inc_ref(); }

operator_info::operator_info(operator_info && info):m_ptr(info.m_ptr) { info.m_ptr = nullptr; }

operator_info::~operator_info() { if (m_ptr) m_ptr->dec_ref(); }

operator_info & operator_info::operator=(operator_info const & s) { LEAN_COPY_REF(operator_info, s); }

operator_info & operator_info::operator=(operator_info && s) { LEAN_MOVE_REF(operator_info, s); }

void operator_info::add_expr(expr const & d) { lean_assert(m_ptr); m_ptr->m_exprs = cons(d, m_ptr->m_exprs); }

bool operator_info::is_overloaded() const { return m_ptr && !is_nil(m_ptr->m_exprs) && !is_nil(cdr(m_ptr->m_exprs)); }

list<expr> const & operator_info::get_denotations() const { lean_assert(m_ptr); return m_ptr->m_exprs; }

fixity operator_info::get_fixity() const { lean_assert(m_ptr); return m_ptr->m_fixity; }

unsigned operator_info::get_precedence() const { lean_assert(m_ptr); return m_ptr->m_precedence; }

name const & operator_info::get_op_name() const { lean_assert(m_ptr); return car(m_ptr->m_op_parts); }

list<name> const & operator_info::get_op_name_parts() const { lean_assert(m_ptr); return m_ptr->m_op_parts; }

operator_info operator_info::copy() const { return operator_info(new imp(*m_ptr)); }

bool operator==(operator_info const & op1, operator_info const & op2) {
    if ((op1.m_ptr == nullptr) != (op2.m_ptr == nullptr))
        return false;
    if (op1.m_ptr)
        return op1.m_ptr->is_eq(*(op2.m_ptr));
    else
        return true;
}

operator_info infix(name const & op, unsigned precedence) {
    return operator_info(new operator_info::imp(op, fixity::Infix, precedence));
}
operator_info infixr(name const & op, unsigned precedence) {
    return operator_info(new operator_info::imp(op, fixity::Infixr, precedence));
}
operator_info infixl(name const & op, unsigned precedence) {
    return operator_info(new operator_info::imp(op, fixity::Infixl, precedence));
}
operator_info prefix(name const & op, unsigned precedence) {
    return operator_info(new operator_info::imp(op, fixity::Prefix, precedence));
}
operator_info postfix(name const & op, unsigned precedence) {
    return operator_info(new operator_info::imp(op, fixity::Postfix, precedence));
}
operator_info mixfixl(unsigned num_parts, name const * parts, unsigned precedence) {
    lean_assert(num_parts > 1); return operator_info(new operator_info::imp(num_parts, parts, fixity::Mixfixl, precedence));
}
operator_info mixfixr(unsigned num_parts, name const * parts, unsigned precedence) {
    lean_assert(num_parts > 1); return operator_info(new operator_info::imp(num_parts, parts, fixity::Mixfixr, precedence));
}
operator_info mixfixc(unsigned num_parts, name const * parts, unsigned precedence) {
    lean_assert(num_parts > 1); return operator_info(new operator_info::imp(num_parts, parts, fixity::Mixfixc, precedence));
}
operator_info mixfixo(unsigned num_parts, name const * parts, unsigned precedence) {
    lean_assert(num_parts > 1); return operator_info(new operator_info::imp(num_parts, parts, fixity::Mixfixo, precedence));
}

char const * to_string(fixity f) {
    switch (f) {
    case fixity::Infix:   return "Infix";
    case fixity::Infixl:  return "Infixl";
    case fixity::Infixr:  return "Infixr";
    case fixity::Prefix:  return "Prefix";
    case fixity::Postfix: return "Postfix";
    case fixity::Mixfixl: return "Mixfixl";
    case fixity::Mixfixr: return "Mixfixr";
    case fixity::Mixfixc: return "Mixfixc";
    case fixity::Mixfixo: return "Mixfixo";
    }
    lean_unreachable();
    return 0;
}

format pp(operator_info const & o) {
    format r;
    switch (o.get_fixity()) {
    case fixity::Infix:
    case fixity::Infixl:
    case fixity::Infixr:
        r = highlight_command(format(to_string(o.get_fixity())));
        if (o.get_precedence() > 1)
            r += format{space(), format(o.get_precedence())};
        r += format{space(), format(o.get_op_name())};
        return r;
    case fixity::Prefix:
    case fixity::Postfix:
    case fixity::Mixfixl:
    case fixity::Mixfixr:
    case fixity::Mixfixc:
    case fixity::Mixfixo:
        r = highlight_command(format("Notation"));
        if (o.get_precedence() > 1)
            r += format{space(), format(o.get_precedence())};
        switch (o.get_fixity()) {
        case fixity::Prefix:
            r += format{space(), format(o.get_op_name()), space(), format("_")};
            return r;
        case fixity::Postfix:
            r += format{space(), format("_"), space(), format(o.get_op_name())};
            return r;
        case fixity::Mixfixl:
            for (auto p : o.get_op_name_parts())
                r += format{space(), format(p), space(), format("_")};
            return r;
        case fixity::Mixfixr:
            for (auto p : o.get_op_name_parts())
                r += format{space(), format("_"), space(), format(p)};
            return r;
        case fixity::Mixfixc: {
            auto parts = o.get_op_name_parts();
            r += format{space(), format(head(parts))};
            for (auto p : tail(parts))
                r += format{space(), format("_"), space(), format(p)};
            return r;
        }
        case fixity::Mixfixo:
            for (auto p : o.get_op_name_parts())
                r += format{space(), format("_"), space(), format(p)};
            r += format{space(), format("_")};
            return r;
        default: lean_unreachable(); break;
        }
    }
    lean_unreachable();
    return format();
}

char const * notation_declaration::keyword() const {
    return to_string(m_op.get_fixity());
}

std::ostream & operator<<(std::ostream & out, operator_info const & o) {
    out << pp(o);
    return out;
}
}