include/graphics/SkTDict.h

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef SkTDict_DEFINED
#define SkTDict_DEFINED

#include "SkChunkAlloc.h"
#include "SkTSearch.h"
#include "SkTDArray.h"

template <typename T> class SkTDict : SkNoncopyable {
public:
    SkTDict(size_t minStringAlloc) : fStrings(minStringAlloc) {}

    void reset()
    {
        fArray.reset();
        fStrings.reset();
    }

    int count() const { return fArray.count(); }

    bool set(const char name[], const T& value)
    {
        return set(name, strlen(name), value);
    }

    bool set(const char name[], size_t len, const T& value)
    {
        SkASSERT(name);

        int index = this->find_index(name, len);

        if (index >= 0)
        {
            fArray[index].fValue = value;
            return false;
        }
        else
        {
            Pair*   pair = fArray.insert(~index);
            char*   copy = (char*)fStrings.alloc(len + 1, SkChunkAlloc::kThrow_AllocFailType);
            memcpy(copy, name, len);
            copy[len] = '\0';
            pair->fName = copy;
            pair->fValue = value;
            return true;
        }
    }

    bool find(const char name[]) const
    {
        return this->find_index(name) >= 0;
    }

    bool find(const char name[], size_t len) const
    {
        return this->find_index(name, len) >= 0;
    }

    bool find(const char name[], T* value) const
    {
        return find(name, strlen(name), value);
    }

    bool find(const char name[], size_t len, T* value) const
    {
        int index = this->find_index(name, len);

        if (index >= 0)
        {
            if (value)
                *value = fArray[index].fValue;
            return true;
        }
        return false;
    }

    bool findKey(T& value, const char** name) const
    {
        Pair* end = fArray.end();
        for (Pair* pair = fArray.begin(); pair < end; pair++) {
            if (pair->fValue != value)
                continue;
            *name = pair->fName;
            return true;
        }
        return false;
    }

public:
    struct Pair {
        const char* fName;
        T           fValue;

        friend int operator<(const Pair& a, const Pair& b)
        {
            return strcmp(a.fName, b.fName);
        }
        friend int operator!=(const Pair& a, const Pair& b)
        {
            return strcmp(a.fName, b.fName);
        }
    };
    friend class Iter;

public:
    class Iter {
    public:
        Iter(const SkTDict<T>& dict)
        {
            fIter = dict.fArray.begin();
            fStop = dict.fArray.end();
        }
        const char* next(T* value)
        {
            const char* name = NULL;
            if (fIter < fStop)
            {
                name = fIter->fName;
                if (value)
                    *value = fIter->fValue;
                fIter += 1;
            }
            return name;
        }
    private:
        Pair*   fIter;
        Pair*   fStop;
    };

private:
    SkTDArray<Pair> fArray;
    SkChunkAlloc    fStrings;

    int find_index(const char name[]) const
    {
        return find_index(name, strlen(name));
    }

    int find_index(const char name[], size_t len) const
    {
        SkASSERT(name);

        int count = fArray.count();
        int index = ~0;

        if (count)
            index = SkStrSearch(&fArray.begin()->fName, count, name, len, sizeof(Pair));
        return index;
    }
    friend class Iter;
};

#endif