#include "JsonHighlighter.h"
#include "Buffer.h"
#include <cctype>

namespace kte {

static bool is_digit(char c) { return c >= '0' && c <= '9'; }

void JSONHighlighter::HighlightLine(const Buffer &buf, int row, std::vector<HighlightSpan> &out) const
{
    const auto &rows = buf.Rows();
    if (row < 0 || static_cast<std::size_t>(row) >= rows.size()) return;
    std::string s = static_cast<std::string>(rows[static_cast<std::size_t>(row)]);
    int n = static_cast<int>(s.size());
    auto push = [&](int a, int b, TokenKind k){ if (b> a) out.push_back({a,b,k}); };

    int i = 0;
    while (i < n) {
        char c = s[i];
        if (c == ' ' || c == '\t') { int j=i+1; while (j<n && (s[j]==' '||s[j]=='\t')) ++j; push(i,j,TokenKind::Whitespace); i=j; continue; }
        if (c == '"') {
            int j = i+1; bool esc=false; while (j < n) { char d = s[j++]; if (esc) { esc=false; continue; } if (d == '\\') { esc=true; continue; } if (d == '"') break; }
            push(i, j, TokenKind::String); i = j; continue;
        }
        if (is_digit(c) || (c=='-' && i+1<n && is_digit(s[i+1]))) {
            int j=i+1; while (j<n && (std::isdigit(static_cast<unsigned char>(s[j]))||s[j]=='.'||s[j]=='e'||s[j]=='E'||s[j]=='+'||s[j]=='-'||s[j]=='_')) ++j; push(i,j,TokenKind::Number); i=j; continue;
        }
        // booleans/null
        if (std::isalpha(static_cast<unsigned char>(c))) {
            int j=i+1; while (j<n && std::isalpha(static_cast<unsigned char>(s[j]))) ++j;
            std::string id = s.substr(i, j-i);
            if (id == "true" || id == "false" || id == "null") push(i,j,TokenKind::Constant); else push(i,j,TokenKind::Identifier);
            i=j; continue;
        }
        // punctuation
        if (c=='{'||c=='}'||c=='['||c==']'||c==','||c==':' ) { push(i,i+1,TokenKind::Punctuation); ++i; continue; }
        // fallback
        push(i,i+1,TokenKind::Default); ++i;
    }
}

} // namespace kte