/* 
 $ gcc -o firewire_changer firewire_changer.c -lraw1394 -lavc1394
 jwestfall@surrealistic.net
*/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <libavc1394/rom1394.h>
#include <libavc1394/avc1394.h>
#include <libraw1394/raw1394.h>

#define AVC1394_PANEL_OPERATION_TUNE 0x67
#define AVC1394_TUNE_COMMAND_LENGTH  0x04

#define AVC1394_TUNE      AVC1394_CTYPE_CONTROL | AVC1394_SUBUNIT_TYPE_PANEL | \
                          AVC1394_PANEL_COMMAND_PASS_THROUGH | \
                          AVC1394_PANEL_OPERATION_TUNE

#define AVC1394_KEY_PRESS AVC1394_CTYPE_CONTROL | AVC1394_SUBUNIT_TYPE_PANEL | \
                          AVC1394_PANEL_COMMAND_PASS_THROUGH | \
                          AVC1394_PANEL_OPERATION_0

#define CHANGE_METHOD_KEY_PRESS 0
#define CHANGE_METHOD_TUNE      1

int  check_device(raw1394handle_t handle, int port, int node);
void method_key_press(raw1394handle_t handle, int port, int node, int channel);
void method_tune(raw1394handle_t handle, int port, int node, int channel);
void usage(void);

int verbose = 0;

int main(int argc, char **argv) 
{
    raw1394handle_t handle;
    int node = -1, channel = -1, port = 0;
    int method = CHANGE_METHOD_KEY_PRESS;
    int c;

    opterr = 0;
    while((c = getopt(argc, argv, "tkn:p:v")) != -1)
    {
        switch(c)
        {
            case 't':
                method = CHANGE_METHOD_TUNE;
                break;
            case 'k':
                method = CHANGE_METHOD_KEY_PRESS;
                break;
            case 'n':
                node = atoi(optarg);
                if (node < 0)
                {
                    printf("invalid node: %d\n", node);
                    exit(1);
                }
                break;
            case 'p':
                port = atoi(optarg);
                if (port < 0)
                {
                    printf("invalid port: %d\n", port);
                    exit(1);
                }
                break;
            case 'v':
                verbose = 1;
                break;
            default:
                printf("bad command line argument: %c\n", optopt);
                usage();
                exit(1);
        }    
    }

    if (optind != argc - 1)
    {
        usage();
        exit(1);
    }

    if (node == -1)
    {
        printf("-n NODE option required\n");
        usage();
        exit(1);
    }

    channel = atoi(argv[optind]);
    if (channel < 0 || channel > 999)
    {
        printf("invalid channel: %d\n", channel);
        exit(1);
    }    

    handle = raw1394_new_handle_on_port(port);
    if (!handle)
    {
        printf("Failed to get raw1394 handle, Port: %d\n", port);
        exit(1);
    }

    if (!check_device(handle, port, node))
    {
        printf("Device Check FAILED, exiting\n");
        exit(1);
    }

    switch (method)
    {
        case CHANGE_METHOD_KEY_PRESS:
            method_key_press(handle, port, node, channel);
            break;
        case CHANGE_METHOD_TUNE:
            method_tune(handle, port, node, channel);
            break;
    }
    
    exit(0);
}

void method_key_press(raw1394handle_t handle, int port, int node, int channel)
{
    quadlet_t cmd[2], *response;
    int i, dig[3];

    dig[2] = (channel % 10);
    dig[1] = (channel % 100)  / 10;
    dig[0] = (channel % 1000) / 100;

    if (verbose)
    {
        printf("Method: Key Press\n");
        printf("Channel: %d, Port: %d, Node: %d\n", channel, port, node);
    }

    for (i = 0; i < 3; i++)
    {
        cmd[0] = AVC1394_KEY_PRESS | dig[i];
        cmd[1] = 0x0;
        
        if (verbose)
            printf("Sending Command (Digit: %d): 0x%08X 0x%08X\n", 
                   dig[i], cmd[0], cmd[1]);
        
        response = avc1394_transaction_block(handle, node, cmd, 2, 1);
        if (response)
        {
            if (AVC1394_MASK_RESPONSE(response[0]) == AVC1394_RESPONSE_ACCEPTED)
            {
                if (verbose)
                    printf("Success, Response: 0x%08X 0x%08X\n", 
                           response[0], response[1]);
            }
            else
            {
                printf("Command Failed (Digit %d), Response: 0x%08X 0x%08X\n",
                        dig[i], response[0], response[1]);
                // add retry instead of exit
                exit(1);
            }
        }
        else
        {
            printf("Command Failed (Digit %d), No Response\n", dig[i]);
            // add retry instead of exit
            exit(1);
        }
        usleep(500000);
    }
}

void method_tune(raw1394handle_t handle, int port, int node, int channel)
{
    quadlet_t cmd[3], *response;

    cmd[0] = AVC1394_TUNE;
    cmd[1] = (AVC1394_TUNE_COMMAND_LENGTH << 24) | (channel << 8);
    cmd[2] = 0x0;

    if (verbose)
    {
        printf("Method: Tune\n");
        printf("Channel: %d, Port: %d, Node: %d\n", channel, port, node);
        printf("Sending Command: 0x%08X 0x%08X 0x%08X\n",
                cmd[0], cmd[1], cmd[2]);
    }

    response = avc1394_transaction_block(handle, node, cmd, 3, 1);
    if (response)
    {
        if (AVC1394_MASK_RESPONSE(response[0]) == AVC1394_RESPONSE_ACCEPTED)
        {
            if (verbose)
                printf("Success, Response: 0x%08X 0x%08X 0x%08X\n", 
                       response[0], response[1], response[2]);
        }
        else
        {
            printf("Command Failed, Response: 0x%08X 0x%08X 0x%08X\n",
                   response[0], response[1], response[2]);
            // add retry instead of exit
            exit(1);
        }
    }
    else
    {
        printf("Command Failed, No Response\n");
        // add retry instead of exit
        exit(1);
    }
}

// verify the device looks like something we could change the channel on
int check_device(raw1394handle_t handle, int port, int node)
{
    if (verbose)
        printf("Checking Device, Port: %d, Node: %d\n  Subunit Type Panel: ",
               port, node);

    if (!avc1394_check_subunit_type(handle, node, AVC1394_SUBUNIT_TYPE_PANEL))
    {
        if (verbose)
            printf("Failed\n");
        return 0;
    }
   
    if (verbose)
        printf("Passed\n  Subunit Type Tuner: ");

    if (!avc1394_check_subunit_type(handle, node, AVC1394_SUBUNIT_TYPE_TUNER))
    {
        if (verbose)
            printf("Failed\n");
        return 0;
    }

   if (verbose)
       printf("Passed\n");

   return 1;
}

void usage(void)
{
    printf("Usage: firewire_changer -k|-t -n NODE [-v] [-p PORT] <channel>\n");
    printf("  -k       use key press method (default)\n");
    printf("  -t       use tune method\n");
    printf("  -n NODE  use node NODE, (required)\n");
    printf("  -p PORT  use adapter PORT, (default:0)\n");
    printf("  -v       be verbose\n");
}