#pragma once

#include <cstddef>
#include <cstdint>
#include <string>
#include <vector>

namespace roro::gemini {

// A page's text, kept as lines in 4 KB chunks: no large contiguous block (with IRC connected the
// largest free block is about 31 KB) and no copy when it grows. About 4 bytes per line on top of
// the text itself. Bytes are fed as they arrive; lines end at LF, a CR before it is dropped.
class TextBuffer {
   public:
    static constexpr size_t kChunk = 4096;

    void append(const char* data, size_t len);
    void finish();  // the last line, if it has no line end
    size_t lineCount() const { return lines_.size(); }
    std::string line(size_t i) const;
    size_t bytes() const { return bytes_; }
    void clear();

   private:
    struct Ref {
        uint16_t chunk;
        uint16_t offset;
        uint16_t length;
    };
    void endLine();

    std::vector<std::string> chunks_;
    std::vector<Ref> lines_;
    std::string partial_;  // the line being received
    size_t bytes_ = 0;
};

}  // namespace roro::gemini