/*
    SDL - Simple DirectMedia Layer
    Copyright (C) 1997-2009 Sam Lantinga

    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

    Carsten Griwodz
    griff@kom.tu-darmstadt.de

    based on linux/SDL_syscdrom.c by Sam Lantinga
*/
#include "SDL_config.h"

#ifdef SDL_CDROM_AIX

/* Functions for system-level CD-ROM audio control */

/*#define DEBUG_CDROM 1*/

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>

#include <sys/ioctl.h>
#include <sys/devinfo.h>
#include <sys/mntctl.h>
#include <sys/statfs.h>
#include <sys/vmount.h>
#include <fstab.h>
#include <sys/scdisk.h>

#include "SDL_cdrom.h"
#include "../SDL_syscdrom.h"

/* The maximum number of CD-ROM drives we'll detect */
#define MAX_DRIVES	16

/* A list of available CD-ROM drives */
static char *SDL_cdlist[MAX_DRIVES];
static dev_t SDL_cdmode[MAX_DRIVES];

/* The system-dependent CD control functions */
static const char *SDL_SYS_CDName(int drive);
static int SDL_SYS_CDOpen(int drive);
static int SDL_SYS_CDGetTOC(SDL_CD * cdrom);
static CDstatus SDL_SYS_CDStatus(SDL_CD * cdrom, int *position);
static int SDL_SYS_CDPlay(SDL_CD * cdrom, int start, int length);
static int SDL_SYS_CDPause(SDL_CD * cdrom);
static int SDL_SYS_CDResume(SDL_CD * cdrom);
static int SDL_SYS_CDStop(SDL_CD * cdrom);
static int SDL_SYS_CDEject(SDL_CD * cdrom);
static void SDL_SYS_CDClose(SDL_CD * cdrom);
static int SDL_SYS_CDioctl(int id, int command, void *arg);

/* Check a drive to see if it is a CD-ROM */
static int
CheckDrive(char *drive, struct stat *stbuf)
{
    int is_cd;
    int cdfd;
    int ret;
    struct devinfo info;

    /* If it doesn't exist, return -1 */
    if (stat(drive, stbuf) < 0) {
        return -1;
    }

    /* If it does exist, verify that it's an available CD-ROM */
    is_cd = 0;
    if (S_ISCHR(stbuf->st_mode) || S_ISBLK(stbuf->st_mode)) {
        cdfd = open(drive, (O_RDONLY | O_EXCL | O_NONBLOCK), 0);
        if (cdfd >= 0) {
            ret = SDL_SYS_CDioctl(cdfd, IOCINFO, &info);
            if (ret < 0) {
                /* Some kind of error */
                is_cd = 0;
            } else {
                if (info.devtype == DD_CDROM) {
                    is_cd = 1;
                } else {
                    is_cd = 0;
                }
            }
            close(cdfd);
        }
#ifdef DEBUG_CDROM
        else {
            fprintf(stderr, "Could not open drive %s (%s)\n", drive,
                    strerror(errno));
        }
#endif
    }
    return is_cd;
}

/* Add a CD-ROM drive to our list of valid drives */
static void
AddDrive(char *drive, struct stat *stbuf)
{
    int i;

    if (SDL_numcds < MAX_DRIVES) {
        /* Check to make sure it's not already in our list.
           This can happen when we see a drive via symbolic link.
         */
        for (i = 0; i < SDL_numcds; ++i) {
            if (stbuf->st_rdev == SDL_cdmode[i]) {
#ifdef DEBUG_CDROM
                fprintf(stderr, "Duplicate drive detected: %s == %s\n",
                        drive, SDL_cdlist[i]);
#endif
                return;
            }
        }

        /* Add this drive to our list */
        i = SDL_numcds;
        SDL_cdlist[i] = SDL_strdup(drive);
        if (SDL_cdlist[i] == NULL) {
            SDL_OutOfMemory();
            return;
        }
        SDL_cdmode[i] = stbuf->st_rdev;
        ++SDL_numcds;
#ifdef DEBUG_CDROM
        fprintf(stderr, "Added CD-ROM drive: %s\n", drive);
#endif
    }
}

static void
CheckMounts()
{
    char *buffer;
    int bufsz;
    struct vmount *ptr;
    int ret;

    buffer = (char *) SDL_malloc(10);
    bufsz = 10;
    if (buffer == NULL) {
        fprintf(stderr,
                "Could not allocate 10 bytes in aix/SDL_syscdrom.c:CheckMounts\n");
        exit(-10);
    }

    do {
        /* mntctrl() returns an array of all mounted filesystems */
        ret = mntctl(MCTL_QUERY, bufsz, buffer);
        if (ret == 0) {
            /* Buffer was too small, realloc.    */
            bufsz = *(int *) buffer;    /* Required size is in first word.   */
            /* (whatever a word is in AIX 4.3.3) */
            /* int seems to be OK in 32bit mode. */
            SDL_free(buffer);
            buffer = (char *) SDL_malloc(bufsz);
            if (buffer == NULL) {
                fprintf(stderr,
                        "Could not allocate %d bytes in aix/SDL_syscdrom.c:CheckMounts\n",
                        bufsz);
                exit(-10);
            }
        } else if (ret < 0) {
#ifdef DEBUG_CDROM
            fprintf(stderr, "Error reading vmount structures\n");
#endif
            return;
        }
    } while (ret == 0);

#ifdef DEBUG_CDROM
    fprintf(stderr, "Read %d vmount structures\n", ret);
#endif
    ptr = (struct vmount *) buffer;
    do {
        switch (ptr->vmt_gfstype) {
        case MNT_CDROM:
            {
                struct stat stbuf;
                char *text;

                text = (char *) ptr + ptr->vmt_data[VMT_OBJECT].vmt_off;
#ifdef DEBUG_CDROM
                fprintf(stderr,
                        "Checking mount path: %s mounted on %s\n", text,
                        (char *) ptr + ptr->vmt_data[VMT_STUB].vmt_off);
#endif
                if (CheckDrive(text, &stbuf) > 0) {
                    AddDrive(text, &stbuf);
                }
            }
            break;
        default:
            break;
        }
        ptr = (struct vmount *) ((char *) ptr + ptr->vmt_length);
        ret--;
    } while (ret > 0);

    free(buffer);
}

static int
CheckNonmounts()
{
#ifdef _THREAD_SAFE
    AFILE_t fsFile = NULL;
    int passNo = 0;
    int ret;
    struct fstab entry;
    struct stat stbuf;

    ret = setfsent_r(&fsFile, &passNo);
    if (ret != 0)
        return -1;
    do {
        ret = getfsent_r(&entry, &fsFile, &passNo);
        if (ret == 0) {
            char *l = SDL_strrchr(entry.fs_spec, '/');
            if (l != NULL) {
                if (!SDL_strncmp("cd", ++l, 2)) {
#ifdef DEBUG_CDROM
                    fprintf(stderr,
                            "Found unmounted CD ROM drive with device name %s\n",
                            entry.fs_spec);
#endif
                    if (CheckDrive(entry.fs_spec, &stbuf) > 0) {
                        AddDrive(entry.fs_spec, &stbuf);
                    }
                }
            }
        }
    } while (ret == 0);
    ret = endfsent_r(&fsFile);
    if (ret != 0)
        return -1;
    return 0;
#else
    struct fstab *entry;
    struct stat stbuf;

    setfsent();
    do {
        entry = getfsent();
        if (entry != NULL) {
            char *l = SDL_strrchr(entry->fs_spec, '/');
            if (l != NULL) {
                if (!SDL_strncmp("cd", ++l, 2)) {
#ifdef DEBUG_CDROM
                    fprintf(stderr,
                            "Found unmounted CD ROM drive with device name %s",
                            entry->fs_spec);
#endif
                    if (CheckDrive(entry->fs_spec, &stbuf) > 0) {
                        AddDrive(entry->fs_spec, &stbuf);
                    }
                }
            }
        }
    } while (entry != NULL);
    endfsent();
#endif
}

int
SDL_SYS_CDInit(void)
{
    char *SDLcdrom;
    struct stat stbuf;

    /* Fill in our driver capabilities */
    SDL_CDcaps.Name = SDL_SYS_CDName;
    SDL_CDcaps.Open = SDL_SYS_CDOpen;
    SDL_CDcaps.GetTOC = SDL_SYS_CDGetTOC;
    SDL_CDcaps.Status = SDL_SYS_CDStatus;
    SDL_CDcaps.Play = SDL_SYS_CDPlay;
    SDL_CDcaps.Pause = SDL_SYS_CDPause;
    SDL_CDcaps.Resume = SDL_SYS_CDResume;
    SDL_CDcaps.Stop = SDL_SYS_CDStop;
    SDL_CDcaps.Eject = SDL_SYS_CDEject;
    SDL_CDcaps.Close = SDL_SYS_CDClose;

    /* Look in the environment for our CD-ROM drive list */
    SDLcdrom = SDL_getenv("SDL_CDROM"); /* ':' separated list of devices */
    if (SDLcdrom != NULL) {
        char *cdpath, *delim;
        size_t len = SDL_strlen(SDLcdrom) + 1;
        cdpath = SDL_stack_alloc(char, len);
        if (cdpath != NULL) {
            SDL_strlcpy(cdpath, SDLcdrom, len);
            SDLcdrom = cdpath;
            do {
                delim = SDL_strchr(SDLcdrom, ':');
                if (delim) {
                    *delim++ = '\0';
                }
#ifdef DEBUG_CDROM
                fprintf(stderr,
                        "Checking CD-ROM drive from SDL_CDROM: %s\n",
                        SDLcdrom);
#endif
                if (CheckDrive(SDLcdrom, &stbuf) > 0) {
                    AddDrive(SDLcdrom, &stbuf);
                }
                if (delim) {
                    SDLcdrom = delim;
                } else {
                    SDLcdrom = NULL;
                }
            } while (SDLcdrom);
            SDL_stack_free(cdpath);
        }

        /* If we found our drives, there's nothing left to do */
        if (SDL_numcds > 0) {
            return (0);
        }
    }

    CheckMounts();
    CheckNonmounts();

    return 0;
}

/* General ioctl() CD-ROM command function */
static int
SDL_SYS_CDioctl(int id, int command, void *arg)
{
    int retval;

    retval = ioctl(id, command, arg);
    if (retval < 0) {
        SDL_SetError("ioctl() error: %s", strerror(errno));
    }
    return retval;
}

static const char *
SDL_SYS_CDName(int drive)
{
    return (SDL_cdlist[drive]);
}

static int
SDL_SYS_CDOpen(int drive)
{
    int fd;
    char *lastsl;
    char *cdromname;
    size_t len;

    /*
     * We found /dev/cd? drives and that is in our list. But we can
     * open only the /dev/rcd? versions of those devices for Audio CD.
     */
    len = SDL_strlen(SDL_cdlist[drive]) + 2;
    cdromname = (char *) SDL_malloc(len);
    SDL_strlcpy(cdromname, SDL_cdlist[drive], len);
    lastsl = SDL_strrchr(cdromname, '/');
    if (lastsl) {
        *lastsl = 0;
        SDL_strlcat(cdromname, "/r", len);
        lastsl = SDL_strrchr(SDL_cdlist[drive], '/');
        if (lastsl) {
            lastsl++;
            SDL_strlcat(cdromname, lastsl, len);
        }
    }
#ifdef DEBUG_CDROM
    fprintf(stderr, "Should open drive %s, opening %s\n", SDL_cdlist[drive],
            cdromname);
#endif

    /*
     * Use exclusive access. Don't use SC_DIAGNOSTICS as xmcd does because they
     * require root priviledges, and we don't want that. SC_SINGLE provides
     * exclusive access with less trouble.
     */
    fd = openx(cdromname, O_RDONLY, NULL, SC_SINGLE);
    if (fd < 0) {
#ifdef DEBUG_CDROM
        fprintf(stderr, "Could not open drive %s (%s)\n", cdromname,
                strerror(errno));
#endif
    } else {
        struct mode_form_op cdMode;
        int ret;
#ifdef DEBUG_CDROM
        cdMode.action = CD_GET_MODE;
        ret = SDL_SYS_CDioctl(fd, DK_CD_MODE, &cdMode);
        if (ret < 0) {
            fprintf(stderr,
                    "Could not get drive mode for %s (%s)\n",
                    cdromname, strerror(errno));
        } else {
            switch (cdMode.cd_mode_form) {
            case CD_MODE1:
                fprintf(stderr,
                        "Drive mode for %s is %s\n",
                        cdromname, "CD-ROM Data Mode 1");
                break;
            case CD_MODE2_FORM1:
                fprintf(stderr,
                        "Drive mode for %s is %s\n",
                        cdromname, "CD-ROM XA Data Mode 2 Form 1");
                break;
            case CD_MODE2_FORM2:
                fprintf(stderr,
                        "Drive mode for %s is %s\n",
                        cdromname, "CD-ROM XA Data Mode 2 Form 2");
                break;
            case CD_DA:
                fprintf(stderr,
                        "Drive mode for %s is %s\n", cdromname, "CD-DA");
                break;
            default:
                fprintf(stderr,
                        "Drive mode for %s is %s\n", cdromname, "unknown");
                break;
            }
        }
#endif

        cdMode.action = CD_CHG_MODE;
        cdMode.cd_mode_form = CD_DA;
        ret = SDL_SYS_CDioctl(fd, DK_CD_MODE, &cdMode);
        if (ret < 0) {
#ifdef DEBUG_CDROM
            fprintf(stderr,
                    "Could not set drive mode for %s (%s)\n",
                    cdromname, strerror(errno));
#endif
            SDL_SetError
                ("ioctl() error: Could not set CD drive mode, %s",
                 strerror(errno));
        } else {
#ifdef DEBUG_CDROM
            fprintf(stderr, "Drive mode for %s set to CD_DA\n", cdromname);
#endif
        }
    }
    SDL_free(cdromname);
    return fd;
}

static int
SDL_SYS_CDGetTOC(SDL_CD * cdrom)
{
    struct cd_audio_cmd cmd;
    struct cd_audio_cmd entry;
    int i;
    int okay;

    cmd.audio_cmds = CD_TRK_INFO_AUDIO;
    cmd.msf_flag = FALSE;
    if (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd) < 0) {
        return -1;
    }

    okay = 0;
    cdrom->numtracks = cmd.indexing.track_index.last_track
        - cmd.indexing.track_index.first_track + 1;
    if (cdrom->numtracks > SDL_MAX_TRACKS) {
        cdrom->numtracks = SDL_MAX_TRACKS;
    }

    /* Read all the track TOC entries */
    for (i = 0; i <= cdrom->numtracks; ++i) {
        if (i == cdrom->numtracks) {
            cdrom->track[i].id = 0xAA;;
        } else {
            cdrom->track[i].id = cmd.indexing.track_index.first_track + i;
        }
        entry.audio_cmds = CD_GET_TRK_MSF;
        entry.indexing.track_msf.track = cdrom->track[i].id;
        if (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &entry) < 0) {
            break;
        } else {
            cdrom->track[i].type = 0;   /* don't know how to detect 0x04 data track */
            cdrom->track[i].offset =
                MSF_TO_FRAMES(entry.indexing.track_msf.mins,
                              entry.indexing.track_msf.secs,
                              entry.indexing.track_msf.frames);
            cdrom->track[i].length = 0;
            if (i > 0) {
                cdrom->track[i - 1].length = cdrom->track[i].offset
                    - cdrom->track[i - 1].offset;
            }
        }
    }
    if (i == (cdrom->numtracks + 1)) {
        okay = 1;
    }
    return (okay ? 0 : -1);
}

/* Get CD-ROM status */
static CDstatus
SDL_SYS_CDStatus(SDL_CD * cdrom, int *position)
{
    CDstatus status;
    struct cd_audio_cmd cmd;
    cmd.audio_cmds = CD_INFO_AUDIO;

    if (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd) < 0) {
#ifdef DEBUG_CDROM
        fprintf(stderr, "ioctl failed in SDL_SYS_CDStatus (%s)\n",
                SDL_GetError());
#endif
        status = CD_ERROR;
    } else {
        switch (cmd.status) {
        case CD_NO_AUDIO:
        case CD_COMPLETED:
            status = CD_STOPPED;
            break;
        case CD_PLAY_AUDIO:
            status = CD_PLAYING;
            break;
        case CD_PAUSE_AUDIO:
            status = CD_PAUSED;
            break;
        case CD_NOT_VALID:
#ifdef DEBUG_CDROM
            fprintf(stderr, "cdStatus failed with CD_NOT_VALID\n");
#endif
            status = CD_ERROR;
            break;
        case CD_STATUS_ERROR:
#ifdef DEBUG_CDROM
            fprintf(stderr, "cdStatus failed with CD_STATUS_ERROR\n");
#endif
            status = CD_ERROR;
            break;
        default:
#ifdef DEBUG_CDROM
            fprintf(stderr, "cdStatus failed with unknown error\n");
#endif
            status = CD_ERROR;
            break;
        }
    }
    if (position) {
        if (status == CD_PLAYING || (status == CD_PAUSED)) {
            *position =
                MSF_TO_FRAMES(cmd.indexing.info_audio.current_mins,
                              cmd.indexing.info_audio.current_secs,
                              cmd.indexing.info_audio.current_frames);
        } else {
            *position = 0;
        }
    }
    return status;
}

/* Start play */
static int
SDL_SYS_CDPlay(SDL_CD * cdrom, int start, int length)
{
    struct cd_audio_cmd cmd;

    /*
     * My CD Rom is muted by default. I think I read that this is new with
     * AIX 4.3. SDL does not change the volume, so I need a kludge. Maybe
     * its better to do this elsewhere?
     */
    cmd.audio_cmds = CD_PLAY_AUDIO | CD_SET_VOLUME;
    cmd.msf_flag = TRUE;
    FRAMES_TO_MSF(start,
                  &cmd.indexing.msf.first_mins,
                  &cmd.indexing.msf.first_secs,
                  &cmd.indexing.msf.first_frames);
    FRAMES_TO_MSF(start + length,
                  &cmd.indexing.msf.last_mins,
                  &cmd.indexing.msf.last_secs, &cmd.indexing.msf.last_frames);
    cmd.volume_type = CD_VOLUME_ALL;
    cmd.all_channel_vol = 255;  /* This is a uchar. What is a good value? No docu! */
    cmd.out_port_0_sel = CD_AUDIO_CHNL_0;
    cmd.out_port_1_sel = CD_AUDIO_CHNL_1;
    cmd.out_port_2_sel = CD_AUDIO_CHNL_2;
    cmd.out_port_3_sel = CD_AUDIO_CHNL_3;

#ifdef DEBUG_CDROM
    fprintf(stderr, "Trying to play from %d:%d:%d to %d:%d:%d\n",
            cmd.indexing.msf.first_mins,
            cmd.indexing.msf.first_secs,
            cmd.indexing.msf.first_frames,
            cmd.indexing.msf.last_mins,
            cmd.indexing.msf.last_secs, cmd.indexing.msf.last_frames);
#endif
    return (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd));
}

/* Pause play */
static int
SDL_SYS_CDPause(SDL_CD * cdrom)
{
    struct cd_audio_cmd cmd;
    cmd.audio_cmds = CD_PAUSE_AUDIO;
    return (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd));
}

/* Resume play */
static int
SDL_SYS_CDResume(SDL_CD * cdrom)
{
    struct cd_audio_cmd cmd;
    cmd.audio_cmds = CD_RESUME_AUDIO;
    return (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd));
}

/* Stop play */
static int
SDL_SYS_CDStop(SDL_CD * cdrom)
{
    struct cd_audio_cmd cmd;
    cmd.audio_cmds = CD_STOP_AUDIO;
    return (SDL_SYS_CDioctl(cdrom->id, DKAUDIO, &cmd));
}

/* Eject the CD-ROM */
static int
SDL_SYS_CDEject(SDL_CD * cdrom)
{
    return (SDL_SYS_CDioctl(cdrom->id, DKEJECT, 0));
}

/* Close the CD-ROM handle */
static void
SDL_SYS_CDClose(SDL_CD * cdrom)
{
    close(cdrom->id);
}

void
SDL_SYS_CDQuit(void)
{
    int i;

    if (SDL_numcds > 0) {
        for (i = 0; i < SDL_numcds; ++i) {
            SDL_free(SDL_cdlist[i]);
        }
        SDL_numcds = 0;
    }
}

#endif /* SDL_CDROM_AIX */
/* vi: set ts=4 sw=4 expandtab: */