#define UNICODE
#define _UNICODE
#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <wchar.h>
#include <stdarg.h>
#include <sys/stat.h>

#define MAX_LINE 2048
#define BUF_SIZE 131072
#define PATH_BUF 32768

typedef struct {
    double silence_db;
    int silence_min_ms;
    double padding_sec;
    double target_lufs;
    double true_peak_db;
    char mp3_bitrate[32];
    int skip_existing;
    int recursive;
} Config;

static Config g_cfg = {-45.0,300,1.0,-14.0,-1.0,"320k",1,1};
static wchar_t g_ffmpeg[PATH_BUF];
static wchar_t g_ffprobe[PATH_BUF];
static FILE *g_log = NULL;
static long g_done = 0, g_total = 0;

static void trim(char *s) {
    char *p=s;
    while (*p==' '||*p=='\t'||*p=='\r'||*p=='\n') p++;
    if (p!=s) memmove(s,p,strlen(p)+1);
    size_t n=strlen(s);
    while(n && (s[n-1]==' '||s[n-1]=='\t'||s[n-1]=='\r'||s[n-1]=='\n')) s[--n]=0;
}
static int ieq(const char *a,const char *b){
    while(*a&&*b){
        char ca=*a,cb=*b;
        if(ca>='A'&&ca<='Z')ca+=32;
        if(cb>='A'&&cb<='Z')cb+=32;
        if(ca!=cb)return 0;
        a++;b++;
    }
    return *a==0&&*b==0;
}
static void load_config_from(const wchar_t *exe_dir){
    wchar_t path[PATH_BUF];
    _snwprintf(path,PATH_BUF-1,L"%ls\\config.ini",exe_dir);
    path[PATH_BUF-1]=0;
    FILE *f=_wfopen(path,L"rb");
    if(!f) return;
    char line[MAX_LINE];
    while(fgets(line,sizeof(line),f)){
        trim(line);
        if(!line[0]||line[0]=='#'||line[0]==';') continue;
        char *eq=strchr(line,'=');
        if(!eq) continue;
        *eq=0;
        char *k=line,*v=eq+1;
        trim(k); trim(v);
        if(ieq(k,"silence_db")) g_cfg.silence_db=strtod(v,NULL);
        else if(ieq(k,"silence_min_ms")) g_cfg.silence_min_ms=atoi(v);
        else if(ieq(k,"padding_sec")) g_cfg.padding_sec=strtod(v,NULL);
        else if(ieq(k,"target_lufs")) g_cfg.target_lufs=strtod(v,NULL);
        else if(ieq(k,"true_peak_db")) g_cfg.true_peak_db=strtod(v,NULL);
        else if(ieq(k,"mp3_bitrate")){
            strncpy(g_cfg.mp3_bitrate,v,sizeof(g_cfg.mp3_bitrate)-1);
            g_cfg.mp3_bitrate[sizeof(g_cfg.mp3_bitrate)-1]=0;
        }
        else if(ieq(k,"skip_existing")) g_cfg.skip_existing=atoi(v)!=0;
        else if(ieq(k,"recursive")) g_cfg.recursive=atoi(v)!=0;
    }
    fclose(f);
}
static int has_ext(const wchar_t *name){
    const wchar_t *p=wcsrchr(name,L'.');
    if(!p) return 0;
    p++;
    const wchar_t *ok[]={L"mp3",L"flac",L"wav",L"m4a",L"aac",L"ogg",L"opus",L"wma",NULL};
    for(int i=0;ok[i];i++) if(_wcsicmp(p,ok[i])==0) return 1;
    return 0;
}
static void path_join(wchar_t *out,size_t cap,const wchar_t *a,const wchar_t *b){
    size_t n=wcslen(a);
    _snwprintf(out,cap-1,L"%ls%ls%ls",a,(n&&a[n-1]==L'\\')?L"":L"\\",b);
    out[cap-1]=0;
}
static int file_exists(const wchar_t *p){
    DWORD a=GetFileAttributesW(p);
    return a!=INVALID_FILE_ATTRIBUTES && !(a&FILE_ATTRIBUTE_DIRECTORY);
}
static int dir_exists(const wchar_t *p){
    DWORD a=GetFileAttributesW(p);
    return a!=INVALID_FILE_ATTRIBUTES && (a&FILE_ATTRIBUTE_DIRECTORY);
}
/* Create parent directories only. IMPORTANT: never create the output filename as a directory. */
static int ensure_dir(const wchar_t *path){
    wchar_t tmp[PATH_BUF];
    wcsncpy(tmp,path,PATH_BUF-1); tmp[PATH_BUF-1]=0;
    size_t n=wcslen(tmp);
    while(n>0 && (tmp[n-1]==L'\\'||tmp[n-1]==L'/')) tmp[--n]=0;
    if(!tmp[0]) return 1;

    size_t start=0;
    if(n>=3 && tmp[1]==L':' && (tmp[2]==L'\\'||tmp[2]==L'/')) start=3;
    for(size_t i=start;i<n;i++){
        if(tmp[i]==L'\\'||tmp[i]==L'/'){
            wchar_t c=tmp[i]; tmp[i]=0;
            if(tmp[0] && !CreateDirectoryW(tmp,NULL)){
                DWORD e=GetLastError();
                if(e!=ERROR_ALREADY_EXISTS) return 0;
            }
            tmp[i]=c;
        }
    }
    if(!CreateDirectoryW(tmp,NULL)){
        DWORD e=GetLastError();
        if(e!=ERROR_ALREADY_EXISTS) return 0;
    }
    return 1;
}
static int ensure_parent_dir(const wchar_t *file){
    wchar_t p[PATH_BUF];
    wcsncpy(p,file,PATH_BUF-1); p[PATH_BUF-1]=0;
    wchar_t *q=wcsrchr(p,L'\\');
    if(!q) q=wcsrchr(p,L'/');
    if(!q) return 1;
    *q=0;
    return ensure_dir(p);
}
static void logw(const wchar_t *fmt,...){
    if(!g_log) return;
    va_list ap; va_start(ap,fmt);
    vfwprintf(g_log,fmt,ap);
    fwprintf(g_log,L"\n");
    fflush(g_log);
    va_end(ap);
}
static void find_tools(const wchar_t *exe_dir){
    path_join(g_ffmpeg,PATH_BUF,exe_dir,L"ffmpeg.exe");
    path_join(g_ffprobe,PATH_BUF,exe_dir,L"ffprobe.exe");
    if(!file_exists(g_ffmpeg)) wcscpy(g_ffmpeg,L"ffmpeg.exe");
    if(!file_exists(g_ffprobe)) wcscpy(g_ffprobe,L"ffprobe.exe");
}
static int run_capture(const wchar_t *cmd, char *out, size_t cap){
    FILE *fp=_wpopen(cmd,L"r");
    if(!fp) return -1;
    size_t n=0; int c;
    while((c=fgetc(fp))!=EOF && n+1<cap) out[n++]=(char)c;
    out[n]=0;
    return _pclose(fp);
}
static int run_cmd(const wchar_t *cmd){
    return _wsystem(cmd);
}
static double parse_hms_duration(const char *p){
    int h=0,m=0; double sec=0.0;
    if(!p) return 0.0;
    if(sscanf(p,"%d:%d:%lf",&h,&m,&sec)==3){
        if(h>=0 && m>=0 && m<60 && sec>=0.0 && sec<60.0)
            return (double)h*3600.0+(double)m*60.0+sec;
    }
    return 0.0;
}

static double get_duration(const wchar_t *in){
    wchar_t cmd[PATH_BUF];
    char buf[8192]={0};

    /* First choice: ffprobe.  Use a format that returns only the number. */
    if(file_exists(g_ffprobe)){
        _snwprintf(cmd,PATH_BUF-1,
            L"\"%ls\" -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 \"%ls\" 2>NUL",
            g_ffprobe,in);
        cmd[PATH_BUF-1]=0;
        if(run_capture(cmd,buf,sizeof(buf))>=0){
            char *p=buf;
            while(*p==' '||*p=='\t'||*p=='\r'||*p=='\n') p++;
            double d=strtod(p,NULL);
            if(d>0.0) return d;
        }
    }

    /*
     * Fallback: ffmpeg itself always knows the input duration and prints it
     * as "Duration: HH:MM:SS.xx".  This also makes the program work when a
     * user has only ffmpeg.exe next to SilenceTrim.exe.
     */
    if(file_exists(g_ffmpeg)){
        memset(buf,0,sizeof(buf));
        _snwprintf(cmd,PATH_BUF-1,
            L"\"%ls\" -hide_banner -i \"%ls\" -f null NUL 2>&1",
            g_ffmpeg,in);
        cmd[PATH_BUF-1]=0;
        if(run_capture(cmd,buf,sizeof(buf))>=0){
            char *p=strstr(buf,"Duration:");
            if(p){
                double d=parse_hms_duration(p+9);
                if(d>0.0) return d;
            }
        }
    }

    return 0.0;
}

/*
 * silencedetect reports every silent section, including silence in the middle.
 * Only accept a leading section whose start is essentially zero, and a trailing
 * section whose end is essentially the file duration. This prevents an internal
 * pause from being mistaken for the beginning/end of a song.
 */
static void detect_edges(const wchar_t *in,double dur,double *start,double *end){
    *start=0; *end=dur;
    if(dur<=0) return;

    wchar_t cmd[PATH_BUF];
    char buf[BUF_SIZE]={0};
    _snwprintf(cmd,PATH_BUF-1,
        L"\"%ls\" -hide_banner -nostats -i \"%ls\" -af silencedetect=noise=%.2fdB:d=%.3f -f null NUL 2>&1",
        g_ffmpeg,in,g_cfg.silence_db,g_cfg.silence_min_ms/1000.0);
    cmd[PATH_BUF-1]=0;
    if(run_capture(cmd,buf,sizeof(buf))<0) return;

    double first_start=-1.0, last_end=-1.0;
    char *p=buf;
    while((p=strstr(p,"silence_start:"))){
        double x=strtod(p+14,NULL);
        if(first_start<0) first_start=x;
        p+=14;
    }
    p=buf;
    while((p=strstr(p,"silence_end:"))){
        char *q=p+12;
        double x=strtod(q,NULL);
        last_end=x;
        p+=12;
    }

    double tol=0.25;
    if(first_start>=0 && first_start<=tol) *start=first_start;
    if(last_end>=0 && last_end>=dur-tol) *end=last_end;

    if(*start<0 || *start>dur) *start=0;
    if(*end<0 || *end>dur) *end=dur;
    if(*end<*start){*start=0;*end=dur;}
}
static const wchar_t *codec_args(const wchar_t *ext,wchar_t *buf,size_t cap){
    if(_wcsicmp(ext,L"mp3")==0){
        _snwprintf(buf,cap-1,L"-c:a libmp3lame -b:a %hs",g_cfg.mp3_bitrate);
    } else if(_wcsicmp(ext,L"flac")==0) wcscpy(buf,L"-c:a flac");
    else if(_wcsicmp(ext,L"wav")==0) wcscpy(buf,L"-c:a pcm_s16le");
    else if(_wcsicmp(ext,L"m4a")==0||_wcsicmp(ext,L"aac")==0) wcscpy(buf,L"-c:a aac -b:a 256k");
    else if(_wcsicmp(ext,L"ogg")==0) wcscpy(buf,L"-c:a libvorbis -q:a 6");
    else if(_wcsicmp(ext,L"opus")==0) wcscpy(buf,L"-c:a libopus -b:a 160k");
    else if(_wcsicmp(ext,L"wma")==0) wcscpy(buf,L"-c:a wmav2 -b:a 192k");
    else wcscpy(buf,L"-c:a libmp3lame -b:a 320k");
    buf[cap-1]=0;
    return buf;
}
static int process_file(const wchar_t *in,const wchar_t *out){
    double dur=get_duration(in);
    if(dur<=0){
        logw(L"ERROR|%ls|duration unavailable",in);
        return -1;
    }

    double ss=0,ee=dur;
    detect_edges(in,dur,&ss,&ee);

    double kept=ee-ss;
    if(kept<0.01){ ss=0; ee=dur; }

    wchar_t ext[16]=L"mp3";
    const wchar_t *dot=wcsrchr(in,L'.');
    if(dot) { wcsncpy(ext,dot+1,15); ext[15]=0; }

    if(!ensure_parent_dir(out)){
        logw(L"ERROR|%ls|cannot create output directory",in);
        return -1;
    }

    wchar_t tmp[PATH_BUF];
    _snwprintf(tmp,PATH_BUF-1,L"%ls.__stmp_%lu_%lu.%ls",
        out,(unsigned long)GetCurrentProcessId(),(unsigned long)GetTickCount(),ext);
    tmp[PATH_BUF-1]=0;

    wchar_t filter[8192];
    /*
     * Add padding after edge trimming. The middle of the song is untouched.
     * aresample is before loudnorm so all formats have a predictable sample rate.
     */
    _snwprintf(filter,8191,
        L"[0:a]atrim=start=%.6f:end=%.6f,asetpts=PTS-STARTPTS[a];"
        L"anullsrc=r=48000:cl=stereo:d=%.6f[pre];"
        L"anullsrc=r=48000:cl=stereo:d=%.6f[post];"
        L"[pre][a][post]concat=n=3:v=0:a=1,aresample=48000,"
        L"loudnorm=I=%.2f:TP=%.2f:LRA=11:linear=true",
        ss,ee,g_cfg.padding_sec,g_cfg.padding_sec,g_cfg.target_lufs,g_cfg.true_peak_db);
    filter[8191]=0;

    wchar_t cargs[256];
    codec_args(ext,cargs,256);

    wchar_t cmd[PATH_BUF];
    _snwprintf(cmd,PATH_BUF-1,
        L"\"%ls\" -hide_banner -nostats -loglevel error -y -i \"%ls\" "
        L"-filter_complex \"%ls\" %ls \"%ls\"",
        g_ffmpeg,in,filter,cargs,tmp);
    cmd[PATH_BUF-1]=0;

    int rc=run_cmd(cmd);
    if(rc!=0){
        DeleteFileW(tmp);
        logw(L"ERROR|%ls|ffmpeg rc=%d|trim %.3f-%.3f",in,rc,ss,ee);
        return -1;
    }
    if(!MoveFileExW(tmp,out,MOVEFILE_REPLACE_EXISTING)){
        DWORD e=GetLastError();
        DeleteFileW(tmp);
        logw(L"ERROR|%ls|move failed Win32=%lu",in,(unsigned long)e);
        return -1;
    }

    logw(L"OK|%ls|trim %.3f-%.3f|pad %.3f|target %.2f|tp %.2f",
        in,ss,ee,g_cfg.padding_sec,g_cfg.target_lufs,g_cfg.true_peak_db);
    return 1;
}
static long count_files(const wchar_t *dir){
    WIN32_FIND_DATAW fd;
    wchar_t pat[PATH_BUF];
    path_join(pat,PATH_BUF,dir,L"*");
    HANDLE h=FindFirstFileW(pat,&fd);
    if(h==INVALID_HANDLE_VALUE) return 0;
    long n=0;
    do{
        if(!wcscmp(fd.cFileName,L".")||!wcscmp(fd.cFileName,L"..")) continue;
        wchar_t p[PATH_BUF];
        path_join(p,PATH_BUF,dir,fd.cFileName);
        if(fd.dwFileAttributes&FILE_ATTRIBUTE_DIRECTORY){
            if(g_cfg.recursive) n+=count_files(p);
        } else if(has_ext(fd.cFileName)) n++;
    }while(FindNextFileW(h,&fd));
    FindClose(h);
    return n;
}
static void process_dir(const wchar_t *in,const wchar_t *root_in,const wchar_t *root_out){
    WIN32_FIND_DATAW fd;
    wchar_t pat[PATH_BUF];
    path_join(pat,PATH_BUF,in,L"*");
    HANDLE h=FindFirstFileW(pat,&fd);
    if(h==INVALID_HANDLE_VALUE) return;

    do{
        if(!wcscmp(fd.cFileName,L".")||!wcscmp(fd.cFileName,L"..")) continue;
        wchar_t src[PATH_BUF];
        path_join(src,PATH_BUF,in,fd.cFileName);

        if(fd.dwFileAttributes&FILE_ATTRIBUTE_DIRECTORY){
            if(g_cfg.recursive) process_dir(src,root_in,root_out);
            continue;
        }
        if(!has_ext(fd.cFileName)) continue;

        const wchar_t *relptr=src+wcslen(root_in);
        while(*relptr==L'\\'||*relptr==L'/') relptr++;

        wchar_t dst[PATH_BUF];
        path_join(dst,PATH_BUF,root_out,relptr);

        if(g_cfg.skip_existing && file_exists(dst)){
            g_done++;
            wprintf(L"[%ld/%ld] SKIP %ls\n",g_done,g_total,src);
            logw(L"SKIP|%ls|already exists",src);
            continue;
        }

        g_done++;
        wprintf(L"[%ld/%ld] %ls\n",g_done,g_total,src);
        int r=process_file(src,dst);
        if(r<0) wprintf(L"  ERROR (see silencetrim.log)\n");
        else wprintf(L"  OK\n");
    }while(FindNextFileW(h,&fd));
    FindClose(h);
}
int wmain(int argc,wchar_t **argv){
    SetConsoleOutputCP(CP_UTF8);

    wchar_t exe_path[PATH_BUF], exe_dir[PATH_BUF];
    GetModuleFileNameW(NULL,exe_path,PATH_BUF);
    exe_path[PATH_BUF-1]=0;
    wcsncpy(exe_dir,exe_path,PATH_BUF-1); exe_dir[PATH_BUF-1]=0;
    wchar_t *slash=wcsrchr(exe_dir,L'\\');
    if(slash) *slash=0; else wcscpy(exe_dir,L".");

    load_config_from(exe_dir);
    find_tools(exe_dir);

    if(argc<2){
        wprintf(L"SilenceTrim.exe INPUT_FOLDER [OUTPUT_FOLDER]\n");
        return 1;
    }

    wchar_t in[PATH_BUF],out[PATH_BUF];
    if(!GetFullPathNameW(argv[1],PATH_BUF,in,NULL)){
        wprintf(L"Input path error.\n"); return 2;
    }
    if(argc>=3){
        if(!GetFullPathNameW(argv[2],PATH_BUF,out,NULL)){
            wprintf(L"Output path error.\n"); return 2;
        }
    } else {
        _snwprintf(out,PATH_BUF-1,L"%ls_Trimmed",in);
        out[PATH_BUF-1]=0;
    }

    if(!dir_exists(in)){
        wprintf(L"Input folder not found: %ls\n",in);
        return 2;
    }

    if(!ensure_dir(out)){
        wprintf(L"Cannot create output folder: %ls\n",out);
        return 3;
    }

    g_total=count_files(in);
    g_done=0;

    wchar_t logp[PATH_BUF];
    path_join(logp,PATH_BUF,out,L"silencetrim.log");
    g_log=_wfopen(logp,L"a, ccs=UTF-8");

    wprintf(L"SilenceTrim (fixed)\n"
            L"Input : %ls\n"
            L"Output: %ls\n"
            L"Files : %ld\n"
            L"Pad   : %.2f sec\n"
            L"LUFS  : %.2f\n"
            L"TP    : %.2f dBTP\n\n",
            in,out,g_total,g_cfg.padding_sec,g_cfg.target_lufs,g_cfg.true_peak_db);
    logw(L"--- start --- files=%ld",g_total);

    if(g_total==0) {
        wprintf(L"No supported audio files found.\n");
    } else {
        process_dir(in,in,out);
    }

    logw(L"--- end --- processed=%ld",g_done);
    if(g_log) fclose(g_log);

    wprintf(L"\nFinished. %ld/%ld entries handled.\n",g_done,g_total);
    return 0;
}