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/**
 * @file
 *   This file implements methods for a signed preference value and its 2-bit unsigned representation.
 */

#include "preference.hpp"

namespace ot {

uint8_t Preference::To2BitUint(int8_t aPrf) { return (aPrf == 0) ? k2BitMedium : ((aPrf > 0) ? k2BitHigh : k2BitLow); }

int8_t Preference::From2BitUint(uint8_t a2BitUint)
{
    static const int8_t kPreferences[] = {
        /* 0 (00)  -> */ kMedium,
        /* 1 (01)  -> */ kHigh,
        /* 2 (10)  -> */ kMedium, // Per RFC-4191, the reserved value (10) MUST be treated as (00)
        /* 3 (11)  -> */ kLow,
    };

    return kPreferences[a2BitUint & k2BitMask];
}

bool Preference::IsValid(int8_t aPrf) { return (aPrf == kHigh) || (aPrf == kMedium) || (aPrf == kLow); }

const char *Preference::ToString(int8_t aPrf) { return (aPrf == 0) ? "medium" : ((aPrf > 0) ? "high" : "low"); }

} // namespace ot