/*
 * Copyright (c) 2015-2016, Intel Corporation
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of Intel Corporation nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef MCCLELLANCOMPILE_H
#define MCCLELLANCOMPILE_H

#include "rdfa.h"
#include "ue2common.h"
#include "util/alloc.h"
#include "util/charreach.h"
#include "util/ue2_containers.h"

#include <memory>
#include <vector>
#include <set>

struct NFA;

namespace ue2 {

struct CompileContext;

struct raw_report_info {
    raw_report_info();
    virtual ~raw_report_info();
    virtual u32 getReportListSize() const = 0; /* in bytes */
    virtual size_t size() const = 0; /* number of lists */
    virtual void fillReportLists(NFA *n, size_t base_offset,
                                 std::vector<u32> &ro /* out */) const = 0;
};

struct escape_info {
    CharReach outs;
    CharReach outs2_single;
    flat_set<std::pair<u8, u8>> outs2;
    bool outs2_broken = false;
    u32 offset = 0;
    u32 outs2_offset = 0;
};

class dfa_build_strat {
public:
    virtual ~dfa_build_strat();
    virtual raw_dfa &get_raw() const = 0;
    virtual std::unique_ptr<raw_report_info> gatherReports(
                               std::vector<u32> &reports /* out */,
                               std::vector<u32> &reports_eod /* out */,
                               u8 *isSingleReport /* out */,
                               ReportID *arbReport  /* out */) const = 0;
    virtual escape_info find_escape_strings(dstate_id_t this_idx) const = 0;
    virtual size_t accelSize(void) const = 0;
    virtual void buildAccel(dstate_id_t this_idx, const escape_info &info,
                            void *accel_out) = 0;
};

class mcclellan_build_strat : public dfa_build_strat {
public:
    explicit mcclellan_build_strat(raw_dfa &r) : rdfa(r) {}
    raw_dfa &get_raw() const override { return rdfa; }
    std::unique_ptr<raw_report_info> gatherReports(
                                  std::vector<u32> &reports /* out */,
                                  std::vector<u32> &reports_eod /* out */,
                                  u8 *isSingleReport /* out */,
                                  ReportID *arbReport  /* out */) const override;
    escape_info find_escape_strings(dstate_id_t this_idx) const override;
    size_t accelSize(void) const override;
    void buildAccel(dstate_id_t this_idx,const escape_info &info,
                    void *accel_out) override;
    virtual u32 max_allowed_offset_accel() const;

private:
    raw_dfa &rdfa;
};

/* accel_states: (optional) on success, is filled with the set of accelerable
 * states */
ue2::aligned_unique_ptr<NFA>
mcclellanCompile(raw_dfa &raw, const CompileContext &cc,
                 std::set<dstate_id_t> *accel_states = nullptr);

/* used internally by mcclellan/haig/gough compile process */
ue2::aligned_unique_ptr<NFA>
mcclellanCompile_i(raw_dfa &raw, dfa_build_strat &strat,
                   const CompileContext &cc,
                   std::set<dstate_id_t> *accel_states = nullptr);

/**
 * \brief Returns the width of the character reach at start.
 */
u32 mcclellanStartReachSize(const raw_dfa *raw);

std::set<ReportID> all_reports(const raw_dfa &rdfa);

bool has_accel_dfa(const NFA *nfa);

} // namespace ue2

#endif