// © 2017 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html

// bytesinkutil.h
// created: 2017sep14 Markus W. Scherer

#include "unicode/utypes.h"
#include "unicode/bytestream.h"
#include "unicode/edits.h"
#include "cmemory.h"
#include "uassert.h"

U_NAMESPACE_BEGIN

class ByteSink;
class CharString;
class Edits;

class U_COMMON_API ByteSinkUtil {
public:
    ByteSinkUtil() = delete;  // all static

    /** (length) bytes were mapped to valid (s16, s16Length). */
    static UBool appendChange(int32_t length,
                              const char16_t *s16, int32_t s16Length,
                              ByteSink &sink, Edits *edits, UErrorCode &errorCode);

    /** The bytes at [s, limit[ were mapped to valid (s16, s16Length). */
    static UBool appendChange(const uint8_t *s, const uint8_t *limit,
                              const char16_t *s16, int32_t s16Length,
                              ByteSink &sink, Edits *edits, UErrorCode &errorCode);

    /** (length) bytes were mapped/changed to valid code point c. */
    static void appendCodePoint(int32_t length, UChar32 c, ByteSink &sink, Edits *edits = nullptr);

    /** The few bytes at [src, nextSrc[ were mapped/changed to valid code point c. */
    static inline void appendCodePoint(const uint8_t *src, const uint8_t *nextSrc, UChar32 c,
                                       ByteSink &sink, Edits *edits = nullptr) {
        appendCodePoint((int32_t)(nextSrc - src), c, sink, edits);
    }

    /** Append the two-byte character (U+0080..U+07FF). */
    static void appendTwoBytes(UChar32 c, ByteSink &sink);

    static UBool appendUnchanged(const uint8_t *s, int32_t length,
                                 ByteSink &sink, uint32_t options, Edits *edits,
                                 UErrorCode &errorCode) {
        if (U_FAILURE(errorCode)) { return false; }
        if (length > 0) { appendNonEmptyUnchanged(s, length, sink, options, edits); }
        return true;
    }

    static UBool appendUnchanged(const uint8_t *s, const uint8_t *limit,
                                 ByteSink &sink, uint32_t options, Edits *edits,
                                 UErrorCode &errorCode);

private:
    static void appendNonEmptyUnchanged(const uint8_t *s, int32_t length,
                                        ByteSink &sink, uint32_t options, Edits *edits);
};

class U_COMMON_API CharStringByteSink : public ByteSink {
public:
    CharStringByteSink(CharString* dest);
    ~CharStringByteSink() override;

    CharStringByteSink() = delete;
    CharStringByteSink(const CharStringByteSink&) = delete;
    CharStringByteSink& operator=(const CharStringByteSink&) = delete;

    void Append(const char* bytes, int32_t n) override;

    char* GetAppendBuffer(int32_t min_capacity,
                          int32_t desired_capacity_hint,
                          char* scratch,
                          int32_t scratch_capacity,
                          int32_t* result_capacity) override;

private:
    CharString& dest_;
};

U_NAMESPACE_END