#include "editor.h"
#include "common/processing.h"
#include "common/library.h"
#include "util/stringUtils.h"
#include "util/path.h"
#include "util/binary.h"

#include <stdlib.h>

#ifdef _WIN32
static inline char* realpath(const char* restrict file_name, char* restrict resolved_name)
{
    assert(resolved_name != NULL);
    return _fullpath(resolved_name, file_name, _MAX_PATH);
}
#endif

static bool extractNvimVersionFromBinary(const char* str, FF_MAYBE_UNUSED uint32_t len, void* userdata)
{
    if (!ffStrStartsWith(str, "NVIM v")) return true;
    ffStrbufSetS((FFstrbuf*) userdata, str + strlen("NVIM v"));
    return false;
}

static bool extractVimVersionFromBinary(const char* str, FF_MAYBE_UNUSED uint32_t len, void* userdata)
{
    if (!ffStrStartsWith(str, "VIM - Vi IMproved ")) return true;
    ffStrbufSetS((FFstrbuf*) userdata, str + strlen("VIM - Vi IMproved "));
    ffStrbufSubstrBeforeFirstC(userdata, ' ');
    return false;
}

static bool extractNanoVersionFromBinary(const char* str, FF_MAYBE_UNUSED uint32_t len, void* userdata)
{
    if (!ffStrStartsWith(str, "GNU nano ")) return true;
    ffStrbufSetS((FFstrbuf*) userdata, str + strlen("GNU nano "));
    return false;
}

const char* ffDetectEditor(FFEditorResult* result)
{
    ffStrbufSetS(&result->name, getenv("VISUAL"));
    if (result->name.length)
        result->type = "Visual";
    else
    {
        ffStrbufSetS(&result->name, getenv("EDITOR"));
        if (result->name.length)
            result->type = "Editor";
        else
            return "$VISUAL or $EDITOR not set";
    }

    if (ffIsAbsolutePath(result->name.chars))
        ffStrbufSet(&result->path, &result->name);
    else
    {
        const char* error = ffFindExecutableInPath(result->name.chars, &result->path);
        if (error) return NULL;
    }

    {
        char buf[PATH_MAX + 1];
        if (!realpath(result->path.chars, buf))
            return NULL;

        // WIN32: Should we handle scoop shim exe here?

        #ifdef __linux__
        if (!ffStrEndsWith(buf, "/snap"))
        #endif
            ffStrbufSetS(&result->path, buf);
    }

    {
        uint32_t index = ffStrbufLastIndexC(&result->path,
            #ifndef _WIN32
            '/'
            #else
            '\\'
            #endif
        );
        if (index == result->path.length)
            return NULL;
        ffStrbufSetS(&result->exe, &result->path.chars[index + 1]);
        if (!result->exe.length)
            return NULL;

        #ifdef _WIN32
        if (ffStrbufEndsWithS(&result->exe, ".exe"))
            ffStrbufSubstrBefore(&result->exe, result->exe.length - 4);
        #endif
    }

    if (!instance.config.general.detectVersion) return NULL;

    if (ffStrbufEqualS(&result->exe, "nvim"))
        ffBinaryExtractStrings(result->path.chars, extractNvimVersionFromBinary, &result->version, (uint32_t) strlen("NVIM v0.0.0"));
    else if (ffStrbufEqualS(&result->exe, "vim") || ffStrbufStartsWithS(&result->exe, "vim."))
        ffBinaryExtractStrings(result->path.chars, extractVimVersionFromBinary, &result->version, (uint32_t) strlen("VIM - Vi IMproved 0.0"));
    else if (ffStrbufEqualS(&result->exe, "nano"))
        ffBinaryExtractStrings(result->path.chars, extractNanoVersionFromBinary, &result->version, (uint32_t) strlen("GNU nano 0.0"));

    if (result->version.length > 0) return NULL;

    const char* param = NULL;
    if (
        ffStrbufEqualS(&result->exe, "nano") ||
        ffStrbufEqualS(&result->exe, "vim") ||
        ffStrbufStartsWithS(&result->exe, "vim.") || // vim.basic/vim.tiny
        ffStrbufEqualS(&result->exe, "nvim") ||
        ffStrbufEqualS(&result->exe, "micro") ||
        ffStrbufEqualS(&result->exe, "emacs") ||
        ffStrbufStartsWithS(&result->exe, "emacs-") || // emacs-29.3
        ffStrbufEqualS(&result->exe, "hx") ||
        ffStrbufEqualS(&result->exe, "code") ||
        ffStrbufEqualS(&result->exe, "pluma") ||
        ffStrbufEqualS(&result->exe, "sublime_text")
    ) param = "--version";
    else if (
        ffStrbufEqualS(&result->exe, "kak") ||
        ffStrbufEqualS(&result->exe, "pico")
    ) param = "-version";
    else if (
        ffStrbufEqualS(&result->exe, "ne")
    ) param = "-h";
    else return NULL;

    ffProcessAppendStdOut(&result->version, (char* const[]){
        result->path.chars,
        (char*) param,
        NULL,
    });

    if (result->version.length == 0)
        return NULL;

    ffStrbufSubstrBeforeFirstC(&result->version, '\n');
    const char* versionStart = strpbrk(result->version.chars, "0123456789");
    if (versionStart != NULL) {
        const char* versionEnd = strpbrk(versionStart, " \t\v\f\r");
        if (versionEnd != NULL)
            ffStrbufSubstrBefore(&result->version, (uint32_t)(versionEnd - result->version.chars));

        if (versionStart != result->version.chars)
            ffStrbufSubstrAfter(&result->version, (uint32_t)(versionStart - result->version.chars - 1));
    }

    return NULL;
}