/* 
 * Copyright (C) 2004 Andrew Beekhof <andrew@beekhof.net>
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 * 
 * This software 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
 * General Public License for more details.
 * 
 * You should have received a copy of the GNU 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
 */

#include <crm_internal.h>

#include <sys/param.h>

#include <crm/crm.h>

#include <stdio.h>
#include <sys/types.h>
#include <unistd.h>

#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#include <crm/msg_xml.h>
#include <crm/common/xml.h>

#include <crm/common/ipc.h>

#include <crm/cib.h>

int exit_code = cib_ok;
GMainLoop *mainloop = NULL;
IPC_Channel *crmd_channel = NULL;

const char *host = NULL;
void usage(const char *cmd, int exit_status);

int command_options = cib_sync_call;
const char *cib_action = NULL;

cib_t *real_cib = NULL;

int dump_data_element(int depth, char **buffer, int *max, int *offset, const char *prefix,
                      xmlNode * data, gboolean formatted);

void print_xml_diff(FILE * where, xmlNode * diff);

static int force_flag = 0;
static int batch_flag = 0;

static char *
get_shadow_prompt(const char *name)
{
    int len = 16;
    char *prompt = NULL;

    CRM_ASSERT(name != NULL);

    len += strlen(name);
    crm_malloc0(prompt, len);

    snprintf(prompt, len, "shadow[%s] # ", name);
    return prompt;
}

static void
shadow_setup(char *name, gboolean do_switch)
{
    const char *prompt = getenv("PS1");
    const char *shell = getenv("SHELL");
    char *new_prompt = get_shadow_prompt(name);

    printf("Setting up shadow instance\n");

    if (safe_str_eq(new_prompt, prompt)) {
        /* nothing to do */
        goto done;

    } else if (batch_flag == FALSE && shell != NULL) {
        setenv("PS1", new_prompt, 1);
        setenv("CIB_shadow", name, 1);
        printf("Type Ctrl-D to exit the crm_shadow shell\n");

        if (strstr(shell, "bash")) {
            execl(shell, "--norc", "--noprofile", NULL);
        } else {
            execl(shell, "--noprofile", NULL);
        }

    } else if (do_switch) {
        printf("To switch to the named shadow instance, paste the following into your shell:\n");

    } else {
        printf
            ("A new shadow instance was created.  To begin using it paste the following into your shell:\n");
    }
    printf("  CIB_shadow=%s ; export CIB_shadow\n", name);

  done:
    crm_free(new_prompt);
}

static void
shadow_teardown(char *name)
{
    const char *prompt = getenv("PS1");
    char *our_prompt = get_shadow_prompt(name);

    if (prompt != NULL && strstr(prompt, our_prompt)) {
        printf("Now type Ctrl-D to exit the crm_shadow shell\n");

    } else {
        printf
            ("Please remember to unset the CIB_shadow variable by pasting the following into your shell:\n");
        printf("  unset CIB_shadow\n");
    }
    crm_free(our_prompt);
}

/* *INDENT-OFF* */
static struct crm_option long_options[] = {
    /* Top-level Options */
    {"help",    0, 0, '?', "\t\tThis text"},
    {"version", 0, 0, '$', "\t\tVersion information"  },
    {"verbose", 0, 0, 'V', "\t\tIncrease debug output"},
    
    {"-spacer-",	1, 0, '-', "\nQueries:"},
    {"which",   no_argument,       NULL, 'w', "\t\tIndicate the active shadow copy"},
    {"display", no_argument,       NULL, 'p', "\t\tDisplay the contents of the active shadow copy"},
    {"edit",    no_argument,       NULL, 'E', "\t\tEdit the contents of the active shadow copy with your favorite $EDITOR"},
    {"diff",    no_argument,       NULL, 'd', "\t\tDisplay the changes in the active shadow copy\n"},
    {"file",    no_argument,       NULL, 'F', "\t\tDisplay the location of the active shadow copy file\n"},

    {"-spacer-",	1, 0, '-', "\nCommands:"},
    {"create",		required_argument, NULL, 'c', "\tCreate the named shadow copy of the active cluster configuration"},
    {"create-empty",	required_argument, NULL, 'e', "Create the named shadow copy with an empty cluster configuration"},
    {"commit",  required_argument, NULL, 'C', "\tUpload the contents of the named shadow copy to the cluster"},
    {"delete",  required_argument, NULL, 'D', "\tDelete the contents of the named shadow copy"},
    {"reset",   required_argument, NULL, 'r', "\tRecreate the named shadow copy from the active cluster configuration"},
    {"switch",  required_argument, NULL, 's', "\t(Advanced) Switch to the named shadow copy"},
    
    {"-spacer-",	1, 0, '-', "\nAdditional Options:"},
    {"force",	no_argument, NULL, 'f', "\t\t(Advanced) Force the action to be performed"},
    {"batch",   no_argument, NULL, 'b', "\t\t(Advanced) Don't spawn a new shell" },
    {"all",     no_argument, NULL, 'a', "\t\t(Advanced) Upload the entire CIB, including status, with --commit" },

    {"-spacer-",	1, 0, '-', "\nExamples:", pcmk_option_paragraph},
    {"-spacer-",	1, 0, '-', "Create a blank shadow configuration:", pcmk_option_paragraph},
    {"-spacer-",	1, 0, '-', " crm_shadow --create-empty myShadow", pcmk_option_example},
    {"-spacer-",	1, 0, '-', "Create a shadow configuration from the running cluster:", pcmk_option_paragraph},
    {"-spacer-",	1, 0, '-', " crm_shadow --create myShadow", pcmk_option_example},
    {"-spacer-",	1, 0, '-', "Display the current shadow configuration:", pcmk_option_paragraph},
    {"-spacer-",	1, 0, '-', " crm_shadow --display", pcmk_option_example},
    {"-spacer-",	1, 0, '-', "Discard the current shadow configuration (named myShadow):", pcmk_option_paragraph},
    {"-spacer-",	1, 0, '-', " crm_shadow --delete myShadow", pcmk_option_example},
    {"-spacer-",	1, 0, '-', "Upload the current shadow configuration (named myShadow) to the running cluster:", pcmk_option_paragraph},
    {"-spacer-",	1, 0, '-', " crm_shadow --commit myShadow", pcmk_option_example},
    
    {0, 0, 0, 0}
};
/* *INDENT-ON* */

int
main(int argc, char **argv)
{
    int rc = 0;
    int flag;
    int argerr = 0;
    static int command = '?';
    char *shadow = NULL;
    char *shadow_file = NULL;
    gboolean full_upload = FALSE;
    gboolean dangerous_cmd = FALSE;
    struct stat buf;
    int option_index = 0;

    crm_log_init("crm_shadow", LOG_CRIT, FALSE, FALSE, argc, argv);
    crm_set_options(NULL, "(query|command) [modifiers]", long_options,
                    "Perform configuration changes in a sandbox before updating the live cluster."
                    "\n\nSets up an environment in which configuration tools (cibadmin, crm_resource, etc) work"
                    " offline instead of against a live cluster, allowing changes to be previewed and tested"
                    " for side-effects.\n");

    if (argc < 2) {
        crm_help('?', LSB_EXIT_EINVAL);
    }

    while (1) {
        flag = crm_get_option(argc, argv, &option_index);
        if (flag == -1 || flag == 0)
            break;

        switch (flag) {
            case 'a':
                full_upload = TRUE;
                break;
            case 'd':
            case 'E':
            case 'p':
            case 'w':
            case 'F':
                command = flag;
                crm_free(shadow);
                shadow = crm_strdup(getenv("CIB_shadow"));
                break;
            case 'e':
            case 'c':
            case 's':
            case 'r':
                command = flag;
                crm_free(shadow);
                shadow = crm_strdup(optarg);
                break;
            case 'C':
            case 'D':
                command = flag;
                dangerous_cmd = TRUE;
                crm_free(shadow);
                shadow = crm_strdup(optarg);
                break;
            case 'V':
                command_options = command_options | cib_verbose;
                crm_bump_log_level();
                break;
            case '$':
            case '?':
                crm_help(flag, LSB_EXIT_OK);
                break;
            case 'f':
                command_options |= cib_quorum_override;
                force_flag = 1;
                break;
            case 'b':
                batch_flag = 1;
                break;
            default:
                printf("Argument code 0%o (%c)" " is not (?yet?) supported\n", flag, flag);
                ++argerr;
                break;
        }
    }

    if (optind < argc) {
        printf("non-option ARGV-elements: ");
        while (optind < argc)
            printf("%s ", argv[optind++]);
        printf("\n");
        crm_help('?', LSB_EXIT_EINVAL);
    }

    if (optind > argc) {
        ++argerr;
    }

    if (argerr) {
        crm_help('?', LSB_EXIT_GENERIC);
    }

    if (command == 'w') {
        /* which shadow instance is active? */
        const char *local = getenv("CIB_shadow");

        if (local == NULL) {
            fprintf(stderr, "No shadow instance provided\n");
            rc = cib_NOTEXISTS;
            goto done;
        }
        fprintf(stdout, "%s\n", local);
        rc = 0;
        goto done;
    }

    if (shadow == NULL) {
        fprintf(stderr, "No shadow instance provided\n");
        fflush(stderr);
        rc = CIBRES_MISSING_FIELD;
        goto done;

    } else if (command != 's' && command != 'c') {
        const char *local = getenv("CIB_shadow");

        if (local != NULL && safe_str_neq(local, shadow) && force_flag == FALSE) {
            fprintf(stderr,
                    "The supplied shadow instance (%s) is not the same as the active one (%s).\n"
                    "  To prevent accidental destruction of the cluster,"
                    " the --force flag is required in order to proceed.\n", shadow, local);
            fflush(stderr);
            rc = LSB_EXIT_GENERIC;
            goto done;
        }
    }

    if (dangerous_cmd && force_flag == FALSE) {
        fprintf(stderr, "The supplied command is considered dangerous."
                "  To prevent accidental destruction of the cluster,"
                " the --force flag is required in order to proceed.\n");
        fflush(stderr);
        rc = LSB_EXIT_GENERIC;
        goto done;
    }

    shadow_file = get_shadow_file(shadow);
    if (command == 'D') {
        /* delete the file */
        rc = stat(shadow_file, &buf);
        if (rc == 0) {
            rc = unlink(shadow_file);
            if (rc != 0) {
                fprintf(stderr, "Could not remove shadow instance '%s': %s\n", shadow,
                        strerror(errno));
                goto done;
            }
        }

        shadow_teardown(shadow);
        goto done;

    } else if (command == 'F') {
        printf("%s\n", shadow_file);
        rc = 0;
        goto done;
    }

    if (command == 'd' || command == 'r' || command == 'c' || command == 'C') {
        real_cib = cib_new_no_shadow();
        rc = real_cib->cmds->signon(real_cib, crm_system_name, cib_command);
        if (rc != cib_ok) {
            fprintf(stderr, "Signon to CIB failed: %s\n", cib_error2string(rc));
            goto done;
        }
    }

    rc = stat(shadow_file, &buf);

    if (command == 'e' || command == 'c') {
        if (rc == 0 && force_flag == FALSE) {
            fprintf(stderr, "A shadow instance '%s' already exists.\n"
                    "  To prevent accidental destruction of the cluster,"
                    " the --force flag is required in order to proceed.\n", shadow);
            rc = cib_EXISTS;
            goto done;
        }

    } else if (rc != 0) {
        fprintf(stderr, "Could not access shadow instance '%s': %s\n", shadow, strerror(errno));
        rc = cib_NOTEXISTS;
        goto done;
    }

    rc = cib_ok;
    if (command == 'c' || command == 'e') {
        xmlNode *output = NULL;

        /* create a shadow instance based on the current cluster config */
        if (command == 'c') {
            rc = real_cib->cmds->query(real_cib, NULL, &output, command_options);
            if (rc != cib_ok) {
                fprintf(stderr, "Could not connect to the CIB: %s\n", cib_error2string(rc));
                goto done;
            }

        } else {
            output = createEmptyCib();
            crm_xml_add(output, XML_ATTR_GENERATION, "0");
            crm_xml_add(output, XML_ATTR_NUMUPDATES, "0");
            crm_xml_add(output, XML_ATTR_GENERATION_ADMIN, "0");
            crm_xml_add(output, XML_ATTR_VALIDATION, LATEST_SCHEMA_VERSION);
        }

        rc = write_xml_file(output, shadow_file, FALSE);
        free_xml(output);

        if (rc < 0) {
            fprintf(stderr, "Could not create the shadow instance '%s': %s\n",
                    shadow, strerror(errno));
            goto done;
        }
        shadow_setup(shadow, FALSE);
        rc = cib_ok;

    } else if (command == 'E') {
        const char *err = NULL;
        char *editor = getenv("EDITOR");

        if (editor == NULL) {
            fprintf(stderr, "No value for $EDITOR defined\n");
            rc = cib_missing;
            goto done;
        }

        execlp(editor, "--", shadow_file, NULL);
        err = strerror(errno);
        fprintf(stderr, "Could not invoke $EDITOR (%s %s): %s\n", editor, shadow_file, err);
        rc = cib_missing;
        goto done;

    } else if (command == 's') {
        shadow_setup(shadow, TRUE);
        rc = 0;
        goto done;

    } else if (command == 'P') {
        /* display the current contents */
        char *output_s = NULL;
        xmlNode *output = filename2xml(shadow_file);

        output_s = dump_xml_formatted(output);
        printf("%s", output_s);

        crm_free(output_s);
        free_xml(output);

    } else if (command == 'd') {
        /* diff against cluster */
        xmlNode *diff = NULL;
        xmlNode *old_config = NULL;
        xmlNode *new_config = filename2xml(shadow_file);

        rc = real_cib->cmds->query(real_cib, NULL, &old_config, command_options);

        if (rc != cib_ok) {
            fprintf(stderr, "Could not query the CIB: %s\n", cib_error2string(rc));
            goto done;
        }

        diff = diff_xml_object(old_config, new_config, FALSE);
        if (diff != NULL) {
            print_xml_diff(stdout, diff);
            rc = 1;
            goto done;
        }
        rc = 0;
        goto done;

    } else if (command == 'C') {
        /* commit to the cluster */
        xmlNode *input = filename2xml(shadow_file);

        if (full_upload) {
            rc = real_cib->cmds->replace(real_cib, NULL, input, command_options);
        } else {
            xmlNode *config = first_named_child(input, XML_CIB_TAG_CONFIGURATION);

            rc = real_cib->cmds->replace(real_cib, XML_CIB_TAG_CONFIGURATION, config,
                                         command_options);
        }

        if (rc != cib_ok) {
            fprintf(stderr, "Could not commit shadow instance '%s' to the CIB: %s\n",
                    shadow, cib_error2string(rc));
            return rc;
        }
        shadow_teardown(shadow);
        free_xml(input);
    }
  done:
    crm_xml_cleanup();
    crm_free(shadow_file);
    crm_free(shadow);
    return rc;
}

#define bhead(buffer, offset) ((*buffer) + (*offset))
#define bremain(max, offset) ((*max) - (*offset))
#define update_buffer_head(len) do {		\
	int total = (*offset) + len + 1;	\
	if(total >= (*max)) { /* too late */	\
	    (*buffer) = EOS; return -1;		\
	} else if(((*max) - total) < 256) {	\
	    (*max) *= 10;			\
	    crm_realloc(*buffer, (*max));	\
	}					\
	(*offset) += len;			\
    } while(0)

extern int print_spaces(char *buffer, int depth, int max);

int
dump_data_element(int depth, char **buffer, int *max, int *offset, const char *prefix,
                  xmlNode * data, gboolean formatted)
{
    int printed = 0;
    int has_children = 0;
    xmlNode *child = NULL;
    const char *name = NULL;

    CRM_CHECK(data != NULL, return 0);

    name = crm_element_name(data);

    CRM_CHECK(name != NULL, return 0);
    CRM_CHECK(buffer != NULL && *buffer != NULL, return 0);

    crm_trace("Dumping %s...", name);

    if (prefix) {
        printed = snprintf(bhead(buffer, offset), bremain(max, offset), "%s", prefix);
        update_buffer_head(printed);
    }

    if (formatted) {
        printed = print_spaces(bhead(buffer, offset), depth, bremain(max, offset));
        update_buffer_head(printed);
    }

    printed = snprintf(bhead(buffer, offset), bremain(max, offset), "<%s", name);
    update_buffer_head(printed);

    if(data) {
        xmlAttrPtr xIter = NULL;
        for(xIter = data->properties; xIter; xIter = xIter->next) {
            const char *prop_name = (const char *)xIter->name;
            const char *prop_value = crm_element_value(data, prop_name);
            crm_trace("Dumping <%s %s=\"%s\"...",
                        name, prop_name, prop_value);
            printed = snprintf(bhead(buffer, offset), bremain(max, offset), " %s=\"%s\"", prop_name, prop_value);
            update_buffer_head(printed);
        }
    }

    has_children = xml_has_children(data);
    printed = snprintf(bhead(buffer, offset), bremain(max, offset), "%s>%s",
                       has_children == 0 ? "/" : "", formatted ? "\n" : "");
    update_buffer_head(printed);

    if (has_children == 0) {
        return 0;
    }

    for (child = __xml_first_child(data); child != NULL; child = __xml_next(child)) {
        if (dump_data_element(depth + 1, buffer, max, offset, prefix, child, formatted) < 0) {
            return -1;
        }
    }

    if (prefix) {
        printed = snprintf(bhead(buffer, offset), bremain(max, offset), "%s", prefix);
        update_buffer_head(printed);
    }

    if (formatted) {
        printed = print_spaces(bhead(buffer, offset), depth, bremain(max, offset));
        update_buffer_head(printed);
    }

    printed =
        snprintf(bhead(buffer, offset), bremain(max, offset), "</%s>%s", name,
                 formatted ? "\n" : "");
    update_buffer_head(printed);
    crm_trace("Dumped %s...", name);

    return has_children;
}

void
print_xml_diff(FILE * where, xmlNode * diff)
{
    char *buffer = NULL;
    xmlNode *child = NULL;
    int max = 1024, len = 0;
    gboolean is_first = TRUE;
    xmlNode *added = find_xml_node(diff, "diff-added", FALSE);
    xmlNode *removed = find_xml_node(diff, "diff-removed", FALSE);

    is_first = TRUE;
    for (child = __xml_first_child(removed); child != NULL; child = __xml_next(child)) {
        len = 0;
        max = 1024;
        crm_free(buffer);
        crm_malloc0(buffer, max);

        if (is_first) {
            is_first = FALSE;
        } else {
            fprintf(where, " --- \n");
        }

        CRM_CHECK(dump_data_element(0, &buffer, &max, &len, "-", child, TRUE) >= 0, continue);
        fprintf(where, "%s", buffer);
    }

    is_first = TRUE;
    for (child = __xml_first_child(added); child != NULL; child = __xml_next(child)) {
        len = 0;
        max = 1024;
        crm_free(buffer);
        crm_malloc0(buffer, max);

        if (is_first) {
            is_first = FALSE;
        } else {
            fprintf(where, " +++ \n");
        }

        CRM_CHECK(dump_data_element(0, &buffer, &max, &len, "+", child, TRUE) >= 0, continue);
        fprintf(where, "%s", buffer);
    }
}