#include "gemini_response.h"

#include <cctype>

namespace roro::gemini {

namespace {
std::string trim(const std::string& s) {
    size_t a = s.find_first_not_of(" \t"), b = s.find_last_not_of(" \t");
    return a == std::string::npos ? "" : s.substr(a, b - a + 1);
}
std::string lower(std::string s) {
    for (auto& c : s) c = static_cast<char>(std::tolower(static_cast<unsigned char>(c)));
    return s;
}
}  // namespace

bool parseHeader(const std::string& line, Header& out) {
    if (line.size() < 2 || !std::isdigit(static_cast<unsigned char>(line[0])) ||
        !std::isdigit(static_cast<unsigned char>(line[1])))
        return false;
    if (line.size() > 2 && line[2] != ' ') return false;
    std::string meta = line.size() > 3 ? line.substr(3) : "";
    if (meta.size() > 1024) return false;
    out.status = (line[0] - '0') * 10 + (line[1] - '0');
    out.meta = meta;
    return true;
}

Category Header::category() const {
    switch (status / 10) {
        case 1: return Category::Input;
        case 2: return Category::Success;
        case 3: return Category::Redirect;
        case 4: return Category::TemporaryFailure;
        case 5: return Category::PermanentFailure;
        case 6: return Category::ClientCertificate;
        default: return Category::Unknown;
    }
}

std::string Header::mimeType() const {
    std::string type = lower(trim(meta.substr(0, meta.find(';'))));
    return type.empty() ? "text/gemini" : type;
}

std::string Header::parameter(const std::string& name) const {
    size_t pos = meta.find(';');
    while (pos != std::string::npos) {
        size_t next = meta.find(';', pos + 1);
        std::string item = trim(meta.substr(pos + 1, next == std::string::npos ? std::string::npos : next - pos - 1));
        size_t eq = item.find('=');
        if (eq != std::string::npos && lower(trim(item.substr(0, eq))) == lower(name)) return trim(item.substr(eq + 1));
        pos = next;
    }
    return "";
}

}  // namespace roro::gemini