pdf2htmlEX/src/HTMLRenderer/TextLineBuffer.h

#ifndef TEXTLINEBUFFER_H__
#define TEXTLINEBUFFER_H__

#include <iostream>
#include <vector>

namespace pdf2htmlEX {

/*
 * Store a series of 
 *  - Text
 *  - Shift
 *  - State change
 * within a line
 */
class HTMLRenderer;
class HTMLRenderer::TextLineBuffer
{
public:
    TextLineBuffer (HTMLRenderer * renderer) : renderer(renderer) { }

    class State {
    public:
        // before output
        void begin(std::ostream & out, const State * prev_state);
        // after output
        void end(std::ostream & out) const;
        // calculate the hash code
        void hash(void);
        // calculate the difference between another State
        int diff(const State & s) const;
        // the offset cause by a single ' ' char
        double single_space_offset(void) const;
        // calculate em_size of this state
        double em_size(void) const;

        enum {
            FONT_ID,
            FONT_SIZE_ID,
            FILL_COLOR_ID,
            STROKE_COLOR_ID,
            LETTER_SPACE_ID,
            WORD_SPACE_ID,
            RISE_ID,

            ID_COUNT
        };

        static long long umask_by_id(int id);

        long long ids[ID_COUNT];

        const FontInfo * font_info;
        double draw_font_size;
        double letter_space;
        double word_space;

        size_t start_idx; // index of the first Text using this state
        // for optimzation
        long long hash_value;
        long long hash_umask; // some states may not be actually used
        bool need_close;

        static const char * const css_class_names []; // class names for each id
    };


    class Offset {
    public:
        size_t start_idx; // should put this Offset right before text[start_idx];
        double width;
    };

    void set_pos(GfxState * state);
    void append_unicodes(const Unicode * u, int l);
    void append_offset(double width);
    void append_state(void);
    void flush(void);

private:
    // retrieve state from renderer
    void set_state(State & state);

    void optimize(void);

    HTMLRenderer * renderer;

    double x, y;
    long long tm_id;

    std::vector<State> states;
    std::vector<Offset> offsets;
    std::vector<Unicode> text;

    // for flush
    std::vector<State*> stack;
};

} // namespace pdf2htmlEX
#endif //TEXTLINEBUFFER_H__