/* -*- Mode: C; c-basic-offset:4 ; indent-tabs-mode:nil -*- */
/*
 * Copyright (c) 2004-2005 The Trustees of Indiana University and Indiana
 *                         University Research and Technology
 *                         Corporation.  All rights reserved.
 * Copyright (c) 2004-2006 The University of Tennessee and The University
 *                         of Tennessee Research Foundation.  All rights
 *                         reserved.
 * Copyright (c) 2004-2005 High Performance Computing Center Stuttgart,
 *                         University of Stuttgart.  All rights reserved.
 * Copyright (c) 2004-2005 The Regents of the University of California.
 *                         All rights reserved.
 * Copyright (c) 2008-2018 Cisco Systems, Inc.  All rights reserved.
 * Copyright (c) 2015      Research Organization for Information Science
 *                         and Technology (RIST). All rights reserved.
 * Copyright (c) 2018      Amazon.com, Inc. or its affiliates.  All Rights reserved.
 * Copyright (c) 2018      Triad National Security, LLC. All rights
 *                         reserved.
 * $COPYRIGHT$
 *
 * Additional copyrights may follow
 *
 * $HEADER$
 */

#include "opal_config.h"

#include <errno.h>
#include <locale.h>
#include <stdio.h>
#include <string.h>

#include "opal/constants.h"
#include "opal/mca/installdirs/installdirs.h"
#include "opal/runtime/opal.h"
#include "opal/util/argv.h"
#include "opal/util/os_path.h"
#include "opal/util/output.h"
#include "opal/util/printf.h"
#include "opal/util/show_help.h"
#include "opal/util/show_help_lex.h"

/*
 * Private variables
 */
static const char *default_filename = "help-messages";
static const char *dash_line
    = "--------------------------------------------------------------------------\n";
static int output_stream = -1;
static char **search_dirs = NULL;
static bool opal_help_want_aggregate = true;

/*
 * Local functions
 */
static int opal_show_vhelp_internal(const char *filename, const char *topic, int want_error_header,
                                    va_list arglist);
static int opal_show_help_internal(const char *filename, const char *topic, int want_error_header,
                                   ...);
static void opal_show_help_finalize(void);

typedef struct {
    pmix_info_t *info;
    pmix_info_t *dirs;
    char *msg;
} opal_log_info_t;

opal_show_help_fn_t opal_show_help = opal_show_help_internal;
opal_show_vhelp_fn_t opal_show_vhelp = opal_show_vhelp_internal;

int opal_show_help_init(void)
{
    opal_output_stream_t lds;

    opal_help_want_aggregate = true;
    mca_base_var_register("opal", NULL, "base", "help_aggregate",
                            "If opal_base_help_aggregate is true, duplicate help messages will be aggregated rather "
                            "than displayed individually.  This can be helpful for parallel jobs that experience "
                            "multiple identical failures; rather than print out the same help/failure message N times, "
                            "display it once with a count of how many processes sent the same message. Default: true.",
                            MCA_BASE_VAR_TYPE_BOOL, NULL, 0, 0, OPAL_INFO_LVL_9,
                            MCA_BASE_VAR_SCOPE_LOCAL, &opal_help_want_aggregate);

    OBJ_CONSTRUCT(&lds, opal_output_stream_t);
    lds.lds_want_stderr = true;
    output_stream = opal_output_open(&lds);

    opal_argv_append_nosize(&search_dirs, opal_install_dirs.opaldatadir);

    opal_finalize_register_cleanup(opal_show_help_finalize);

    return OPAL_SUCCESS;
}

static void opal_show_help_finalize(void)
{
    opal_output_close(output_stream);
    output_stream = -1;

    /* destruct the search list */
    if (NULL != search_dirs) {
        opal_argv_free(search_dirs);
        search_dirs = NULL;
    }
}

static void opal_show_help_output(const char *msg) {

    if(-1 < output_stream) {
        opal_output(output_stream, "%s", msg);
    }
    else {
        // opal_show_help() was not initialized yet, but we should still be
        // able to print to stderr.
        fprintf(stderr, "%s", msg);
    }
}

static void opal_show_help_cbfunc(pmix_status_t status, void *cbdata)
{
    opal_log_info_t *info = (opal_log_info_t *) cbdata;
    if(PMIX_SUCCESS != status && PMIX_OPERATION_SUCCEEDED != status) {
        // Aggregation/de-duplication functionality is *probably* lost,
        // but let's print the error anyway since duplicate error messages
        // is better than hiding it.
        opal_show_help_output(info->msg);
    }
    PMIX_INFO_DESTRUCT(info->info);
    if(info->dirs) {
        PMIX_INFO_DESTRUCT(info->dirs);
    }
    free(info->msg);
    free(info);
}

static void local_delivery(const char *file, const char *topic, char *msg) {
    pmix_info_t *info, *dirs = NULL;
    int ninfo = 0, ndirs = 0;
    PMIX_INFO_CREATE(info, 1);
    PMIX_INFO_LOAD(&info[ninfo++], PMIX_LOG_STDERR, msg, PMIX_STRING);

    opal_log_info_t *cbdata = calloc(1, sizeof(opal_log_info_t));
    if(opal_help_want_aggregate) {
// Not available in PMIx releases of v4.1.2 and earlier.
// This should be available in future v4.1 and v4.2 releases,
// as well as future major releases.
// Disabling the aggregate behavior here, but still log it, as
// seeing duplicate messages is better than not seeing anything at all.
#ifdef PMIX_LOG_AGG
        PMIX_INFO_CREATE(dirs, 3);
        PMIX_INFO_LOAD(&dirs[ndirs++], PMIX_LOG_AGG, &opal_help_want_aggregate, PMIX_BOOL);
        PMIX_INFO_LOAD(&dirs[ndirs++], PMIX_LOG_KEY, file, PMIX_STRING);
        PMIX_INFO_LOAD(&dirs[ndirs++], PMIX_LOG_VAL, topic, PMIX_STRING);
        cbdata->dirs = dirs;
#endif
    }

    cbdata->info = info;
    cbdata->msg  = msg;

    // PMIx and the runtime will aggregate, de-duplicate, and print this
    // message to stderr.
    pmix_status_t rc = PMIx_Log_nb(info, ninfo, dirs, ndirs, opal_show_help_cbfunc, cbdata);
    if(PMIX_SUCCESS != rc) {
        // Aggregation/de-duplication functionality is *definitely* lost,
        // but let's print the error anyway since duplicate error messages
        // is better than hiding it.
        opal_show_help_output(msg);
        PMIX_INFO_DESTRUCT(info);
        if(opal_help_want_aggregate) {
            PMIX_INFO_DESTRUCT(dirs);
        }
        free(msg);
        free(cbdata);
    }
}

static void opal_show_help_error(const char *file, const char *topic) {
    char *msg;
    opal_asprintf(&msg,
                   "%sSorry!  You were supposed to get help about:\n    %s\nfrom the file:\n  "
                   "  %s\nBut I couldn't find that topic in the file.  Sorry!\n%s",
                    dash_line, topic ? topic : "(Not specified)", file ? file : "(Not specified)", dash_line);
    local_delivery(topic, file, msg);
}

/*
 * Make one big string with all the lines.  This isn't the most
 * efficient method in the world, but we're going for clarity here --
 * not optimization.  :-)
 */
static int array2string(char **outstring, int want_error_header, char **lines)
{
    int i, count;
    size_t len;

    /* See how much space we need */

    len = want_error_header ? 2 * strlen(dash_line) : 0;
    count = opal_argv_count(lines);
    for (i = 0; i < count; ++i) {
        if (NULL == lines[i]) {
            break;
        }
        len += strlen(lines[i]) + 1;
    }

    /* Malloc it out */

    (*outstring) = (char *) malloc(len + 1);
    if (NULL == *outstring) {
        return OPAL_ERR_OUT_OF_RESOURCE;
    }

    /* Fill the big string */

    *(*outstring) = '\0';
    if (want_error_header) {
        strcat(*outstring, dash_line);
    }
    for (i = 0; i < count; ++i) {
        if (NULL == lines[i]) {
            break;
        }
        strcat(*outstring, lines[i]);
        strcat(*outstring, "\n");
    }
    if (want_error_header) {
        strcat(*outstring, dash_line);
    }

    return OPAL_SUCCESS;
}

/*
 * Find the right file to open
 */
static int open_file(const char *base, const char *topic)
{
    char *filename = NULL, *err_msg = NULL;
    size_t base_len;
    int i, rc = OPAL_SUCCESS;

    /* If no filename was supplied, use the default */
    if (NULL == base) {
        base = default_filename;
    }

    /* if this is called prior to someone initializing the system,
     * then don't try to look
     */
    if (NULL != search_dirs) {
        /* Try to open the file.  If we can't find it, try it with a .txt
         * extension.
         */
        for (i = 0; NULL != search_dirs[i]; i++) {
            filename = opal_os_path(false, search_dirs[i], base, NULL);
            if(filename) {
                opal_show_help_yyin = fopen(filename, "r");
                if (NULL == opal_show_help_yyin) {
                    opal_asprintf(&err_msg, "%s: %s", filename, strerror(errno));
                    base_len = strlen(base);
                    if (4 > base_len || 0 != strcmp(base + base_len - 4, ".txt")) {
                        free(filename);
                        opal_asprintf(&filename, "%s%s%s.txt", search_dirs[i], OPAL_PATH_SEP, base);
                        opal_show_help_yyin = fopen(filename, "r");
                    }
                }
                if (NULL != opal_show_help_yyin) {
                    break;
                }
            }
        }
    }

    /* If we still couldn't open it, then something is wrong */
    if (NULL == opal_show_help_yyin) {
        const char *file_ptr = NULL;
        if(err_msg) {
            file_ptr = err_msg;
        }
        else if(filename) {
            file_ptr = filename;
        }
        else {
            file_ptr = base;
        }
        opal_show_help_error(file_ptr, topic);
        rc = OPAL_ERR_NOT_FOUND;
        goto cleanup;
    }

    /* Set the buffer */
    opal_show_help_init_buffer(opal_show_help_yyin);

cleanup:

    if(filename) {
        free(filename);
    }
    if(err_msg) {
        free(err_msg);
    }

    return rc;
}

/*
 * In the file that has already been opened, find the topic that we're
 * supposed to output
 */
static int find_topic(const char *base, const char *topic)
{
    int token, ret;
    char *tmp;

    /* Examine every topic */

    while (1) {
        token = opal_show_help_yylex();
        switch (token) {
        case OPAL_SHOW_HELP_PARSE_TOPIC:
            tmp = strdup(opal_show_help_yytext);
            if (NULL == tmp) {
                return OPAL_ERR_OUT_OF_RESOURCE;
            }
            tmp[strlen(tmp) - 1] = '\0';
            ret = strcmp(tmp + 1, topic);
            free(tmp);
            if (0 == ret) {
                return OPAL_SUCCESS;
            }
            break;

        case OPAL_SHOW_HELP_PARSE_MESSAGE:
            break;

        case OPAL_SHOW_HELP_PARSE_DONE: {
           opal_show_help_error(topic, base);
           return OPAL_ERR_NOT_FOUND;
        }
        default:
            break;
        }
    }

    /* Never get here */
}

/*
 * We have an open file, and we're pointed at the right topic.  So
 * read in all the lines in the topic and make a list of them.
 */
static int read_topic(char ***array)
{
    int token, rc;

    while (1) {
        token = opal_show_help_yylex();
        switch (token) {
        case OPAL_SHOW_HELP_PARSE_MESSAGE:
            /* opal_argv_append_nosize does strdup(opal_show_help_yytext) */
            rc = opal_argv_append_nosize(array, opal_show_help_yytext);
            if (rc != OPAL_SUCCESS) {
                return rc;
            }
            break;

        default:
            return OPAL_SUCCESS;
            break;
        }
    }

    /* Never get here */
}

static int load_array(char ***array, const char *filename, const char *topic)
{
    int ret;

    if (OPAL_SUCCESS != (ret = open_file(filename, topic))) {
        return ret;
    }

    ret = find_topic(filename, topic);
    if (OPAL_SUCCESS == ret) {
        ret = read_topic(array);
    }

    fclose(opal_show_help_yyin);
    opal_show_help_yylex_destroy();

    if (OPAL_SUCCESS != ret) {
        opal_argv_free(*array);
    }

    return ret;
}

char *opal_show_help_vstring(const char *filename, const char *topic, int want_error_header,
                             va_list arglist)
{
    int rc;
    char *single_string, *output, **array = NULL;

    /* Load the message */
    if (OPAL_SUCCESS != (rc = load_array(&array, filename, topic))) {
        return NULL;
    }

    /* Convert it to a single raw string */
    rc = array2string(&single_string, want_error_header, array);

    if (OPAL_SUCCESS == rc) {
        /* Apply the formatting to make the final output string */
        opal_vasprintf(&output, single_string, arglist);
        free(single_string);
    }

    opal_argv_free(array);
    return (OPAL_SUCCESS == rc) ? output : NULL;
}

char *opal_show_help_string(const char *filename, const char *topic, int want_error_handler, ...)
{
    char *output;
    va_list arglist;

    va_start(arglist, want_error_handler);
    output = opal_show_help_vstring(filename, topic, want_error_handler, arglist);
    va_end(arglist);

    return output;
}

static int opal_show_vhelp_internal(const char *filename, const char *topic, int want_error_header,
                                    va_list arglist)
{
    char *output;

    /* Convert it to a single string */
    output = opal_show_help_vstring(filename, topic, want_error_header, arglist);

    /* If we got a single string, output it with formatting */
    if (NULL != output) {
        local_delivery(filename, topic, output);
    }

    return (NULL == output) ? OPAL_ERROR : OPAL_SUCCESS;
}

static int opal_show_help_internal(const char *filename, const char *topic, int want_error_header,
                                   ...)
{
    va_list arglist;
    int rc;

    /* Convert it to a single string */
    va_start(arglist, want_error_header);
    rc = opal_show_vhelp(filename, topic, want_error_header, arglist);
    va_end(arglist);

    return rc;
}

int opal_show_help_add_dir(const char *directory)
{
    opal_argv_append_nosize(&search_dirs, directory);
    return OPAL_SUCCESS;
}