/*
 * clipboard.hpp
 * Simple plain-text clipboard helpers for MontaukOS GUI apps
 * Copyright (c) 2026 Daniel Hammer
 */

#pragma once

#include <montauk/syscall.h>
#include <montauk/string.h>
#include <montauk/heap.h>
#include <montauk/utf8.h>

namespace gui {

    // The clipboard carries UTF-8. Text that is not well-formed (legacy
    // Windows-1252 bytes) is converted on the way in and on the way out, so
    // every reader can assume valid UTF-8.
    inline char* clipboard_utf8_copy(const char* text, int len, int* out_len) {
        int cap = len * 3 + 1;   // each stray byte grows to at most 3
        char* out = (char*)montauk::malloc(cap);
        if (!out) return nullptr;
        *out_len = montauk::utf8::normalize(text, len, out, cap);
        return out;
    }

    inline bool clipboard_set_text(const char* text, int len) {
        if (len < 0) return false;
        if (len > 0 && text == nullptr) return false;
        if (len > 0 && !montauk::utf8::valid(text, len)) {
            int fixed_len = 0;
            char* fixed = clipboard_utf8_copy(text, len, &fixed_len);
            if (!fixed) return false;
            bool ok = montauk::clipboard_set_text(fixed, (uint32_t)fixed_len) == 0;
            montauk::mfree(fixed);
            return ok;
        }
        return montauk::clipboard_set_text(text, (uint32_t)len) == 0;
    }

    inline bool clipboard_set_text(const char* text) {
        return clipboard_set_text(text, text ? montauk::slen(text) : 0);
    }

    inline bool clipboard_get_info(montauk::abi::ClipboardInfo* out) {
        if (out == nullptr) return false;
        return montauk::clipboard_get_info(out) == 0;
    }

    inline bool clipboard_has_text() {
        montauk::abi::ClipboardInfo info = {};
        return clipboard_get_info(&info) && info.textBytes > 0;
    }

    inline char* clipboard_get_text_alloc(int* out_len = nullptr, uint64_t* out_serial = nullptr) {
        if (out_len) *out_len = 0;
        if (out_serial) *out_serial = 0;

        montauk::abi::ClipboardInfo info = {};
        if (!clipboard_get_info(&info) || info.textBytes == 0)
            return nullptr;

        uint32_t cap = info.textBytes + 1;
        char* text = (char*)montauk::malloc(cap);
        if (text == nullptr) return nullptr;

        uint32_t actual_len = 0;
        uint64_t serial = 0;
        if (montauk::clipboard_get_text(text, info.textBytes, &actual_len, &serial) != 0 ||
            actual_len > info.textBytes) {
            montauk::mfree(text);
            return nullptr;
        }

        text[actual_len] = '\0';
        if (!montauk::utf8::valid(text, (int)actual_len)) {
            int fixed_len = 0;
            char* fixed = clipboard_utf8_copy(text, (int)actual_len, &fixed_len);
            montauk::mfree(text);
            if (!fixed) return nullptr;
            text = fixed;
            actual_len = (uint32_t)fixed_len;
        }
        if (out_len) *out_len = (int)actual_len;
        if (out_serial) *out_serial = serial;
        return text;
    }

    inline bool clipboard_clear() {
        return montauk::clipboard_clear() == 0;
    }

}