/*
*/

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <pthread.h>
#include <time.h>
#include <stdint.h>

#include <libpq-fe.h>

#include "nominatim.h"
#include "index.h"
#include "export.h"
#include "postgresql.h"

extern int verbose;

void nominatim_index(int rank_min, int rank_max, int num_threads, const char *conninfo, const char *structuredoutputfile)
{
    struct index_thread_data * thread_data;
    pthread_mutex_t count_mutex = PTHREAD_MUTEX_INITIALIZER;
    int tuples, count, sleepcount;

    time_t rankStartTime;
    int rankTotalTuples;
    int rankCountTuples;
    float rankPerSecond;

    PGconn *conn;
    PGresult * res;
    PGresult * resSectors;
    PGresult * resPlaces;
    PGresult * resNULL;

    int rank;
    int i;
    int iSector;
    int iResult;
    int bSkip;

    const char *paramValues[2];
    int         paramLengths[2];
    int         paramFormats[2];
    uint32_t    paramRank;
    uint32_t    paramSector;
    uint32_t    sector;

    xmlTextWriterPtr writer;
    pthread_mutex_t writer_mutex = PTHREAD_MUTEX_INITIALIZER;

    Oid pg_prepare_params[2];

    conn = PQconnectdb(conninfo);
    if (PQstatus(conn) != CONNECTION_OK)
    {
        fprintf(stderr, "Connection to database failed: %s\n", PQerrorMessage(conn));
        exit(EXIT_FAILURE);
    }

    pg_prepare_params[0] = PG_OID_INT4;
    res = PQprepare(conn, "index_sectors",
                    "select geometry_sector,count(*) from placex where rank_search = $1 and indexed_status > 0 group by geometry_sector order by geometry_sector",
                    1, pg_prepare_params);
    if (PQresultStatus(res) != PGRES_COMMAND_OK)
    {
        fprintf(stderr, "Failed preparing index_sectors: %s\n", PQerrorMessage(conn));
        exit(EXIT_FAILURE);
    }
    PQclear(res);

    pg_prepare_params[0] = PG_OID_INT4;
    res = PQprepare(conn, "index_nosectors",
                    "select 0::integer,count(*) from placex where rank_search = $1 and indexed_status > 0",
                    1, pg_prepare_params);
    if (PQresultStatus(res) != PGRES_COMMAND_OK)
    {
        fprintf(stderr, "Failed preparing index_sectors: %s\n", PQerrorMessage(conn));
        exit(EXIT_FAILURE);
    }
    PQclear(res);

    pg_prepare_params[0] = PG_OID_INT4;
    pg_prepare_params[1] = PG_OID_INT4;
    res = PQprepare(conn, "index_sector_places",
                    "select place_id from placex where rank_search = $1 and geometry_sector = $2 and indexed_status > 0",
                    2, pg_prepare_params);
    if (PQresultStatus(res) != PGRES_COMMAND_OK)
    {
        fprintf(stderr, "Failed preparing index_sector_places: %s\n", PQerrorMessage(conn));
        exit(EXIT_FAILURE);
    }
    PQclear(res);

    pg_prepare_params[0] = PG_OID_INT4;
    res = PQprepare(conn, "index_nosector_places",
                    "select place_id from placex where rank_search = $1 and indexed_status > 0 order by geometry_sector",
                    1, pg_prepare_params);
    if (PQresultStatus(res) != PGRES_COMMAND_OK)
    {
        fprintf(stderr, "Failed preparing index_nosector_places: %s\n", PQerrorMessage(conn));
        exit(EXIT_FAILURE);
    }
    PQclear(res);

    // Build the data for each thread
    thread_data = (struct index_thread_data *)malloc(sizeof(struct index_thread_data)*num_threads);
    for (i = 0; i < num_threads; i++)
    {
        thread_data[i].conn = PQconnectdb(conninfo);
        if (PQstatus(thread_data[i].conn) != CONNECTION_OK)
        {
            fprintf(stderr, "Connection to database failed: %s\n", PQerrorMessage(thread_data[i].conn));
            exit(EXIT_FAILURE);
        }

        pg_prepare_params[0] = PG_OID_INT4;
        res = PQprepare(thread_data[i].conn, "index_placex",
                        "update placex set indexed_status = 0 where place_id = $1",
                        1, pg_prepare_params);
        if (PQresultStatus(res) != PGRES_COMMAND_OK)
        {
            fprintf(stderr, "Failed preparing index_placex: %s\n", PQerrorMessage(conn));
            exit(EXIT_FAILURE);
        }
        PQclear(res);

        res = PQexec(thread_data[i].conn, "set enable_seqscan = false");
        if (PQresultStatus(res) != PGRES_COMMAND_OK)
        {
            fprintf(stderr, "Failed disabling sequential scan: %s\n", PQerrorMessage(conn));
            exit(EXIT_FAILURE);
        }
        PQclear(res);

        nominatim_exportCreatePreparedQueries(thread_data[i].conn);
    }

    // Create the output file
    writer = NULL;
    if (structuredoutputfile)
    {
        writer = nominatim_exportXMLStart(structuredoutputfile);
    }

    fprintf(stderr, "Starting indexing rank (%i to %i) using %i treads\n", rank_min, rank_max, num_threads);

    for (rank = rank_min; rank <= rank_max; rank++)
    {
        fprintf(stderr, "Starting rank %d\n", rank);
        rankCountTuples = 0;
        rankPerSecond = 0;

        paramRank = PGint32(rank);
        paramValues[0] = (char *)&paramRank;
        paramLengths[0] = sizeof(paramRank);
        paramFormats[0] = 1;
//        if (rank < 16)
//            resSectors = PQexecPrepared(conn, "index_nosectors", 1, paramValues, paramLengths, paramFormats, 1);
//        else
        resSectors = PQexecPrepared(conn, "index_sectors", 1, paramValues, paramLengths, paramFormats, 1);

        if (PQresultStatus(resSectors) != PGRES_TUPLES_OK)
        {
            fprintf(stderr, "index_sectors: SELECT failed: %s", PQerrorMessage(conn));
            PQclear(resSectors);
            exit(EXIT_FAILURE);
        }
        if (PQftype(resSectors, 0) != PG_OID_INT4)
        {
            fprintf(stderr, "Sector value has unexpected type\n");
            PQclear(resSectors);
            exit(EXIT_FAILURE);
        }
        if (PQftype(resSectors, 1) != PG_OID_INT8)
        {
            fprintf(stderr, "Sector value has unexpected type\n");
            PQclear(resSectors);
            exit(EXIT_FAILURE);
        }

        rankTotalTuples = 0;
        for (iSector = 0; iSector < PQntuples(resSectors); iSector++)
        {
            rankTotalTuples += PGint64(*((uint64_t *)PQgetvalue(resSectors, iSector, 1)));
        }

        rankStartTime = time(0);
        for (iSector = 0; iSector <= PQntuples(resSectors); iSector++)
        {
            if (iSector > 0)
            {
                resPlaces = PQgetResult(conn);
                if (PQresultStatus(resPlaces) != PGRES_TUPLES_OK)
                {
                    fprintf(stderr, "index_sector_places: SELECT failed: %s", PQerrorMessage(conn));
                    PQclear(resPlaces);
                    exit(EXIT_FAILURE);
                }
                if (PQftype(resPlaces, 0) != PG_OID_INT4)
                {
                    fprintf(stderr, "Place_id value has unexpected type\n");
                    PQclear(resPlaces);
                    exit(EXIT_FAILURE);
                }
                resNULL = PQgetResult(conn);
                if (resNULL != NULL)
                {
                    fprintf(stderr, "Unexpected non-null response\n");
                    exit(EXIT_FAILURE);
                }
            }

            if (iSector < PQntuples(resSectors))
            {
                sector = PGint32(*((uint32_t *)PQgetvalue(resSectors, iSector, 0)));
//                fprintf(stderr, "\n Starting sector %d size %ld\n", sector, PGint64(*((uint64_t *)PQgetvalue(resSectors, iSector, 1))));

                // Get all the place_id's for this sector
                paramRank = PGint32(rank);
                paramValues[0] = (char *)&paramRank;
                paramLengths[0] = sizeof(paramRank);
                paramFormats[0] = 1;
                paramSector = PGint32(sector);
                paramValues[1] = (char *)&paramSector;
                paramLengths[1] = sizeof(paramSector);
                paramFormats[1] = 1;
                if (rankTotalTuples-rankCountTuples < num_threads*1000)
		{
                    iResult = PQsendQueryPrepared(conn, "index_nosector_places", 1, paramValues, paramLengths, paramFormats, 1);
		}
                else
		{
                    iResult = PQsendQueryPrepared(conn, "index_sector_places", 2, paramValues, paramLengths, paramFormats, 1);
		}
                if (!iResult)
                {
                    fprintf(stderr, "index_sector_places: SELECT failed: %s", PQerrorMessage(conn));
                    PQclear(resPlaces);
                    exit(EXIT_FAILURE);
                }
            }

            if (iSector > 0)
            {
                count = 0;
                rankPerSecond = 0;
                tuples = PQntuples(resPlaces);

                if (tuples > 0)
                {
                    // Spawn threads
                    for (i = 0; i < num_threads; i++)
                    {
                        thread_data[i].res = resPlaces;
                        thread_data[i].tuples = tuples;
                        thread_data[i].count = &count;
                        thread_data[i].count_mutex = &count_mutex;
                        thread_data[i].writer = writer;
                        thread_data[i].writer_mutex = &writer_mutex;
                        pthread_create(&thread_data[i].thread, NULL, &nominatim_indexThread, (void *)&thread_data[i]);
                    }

                    // Monitor threads to give user feedback
                    sleepcount = 0;
                    while (count < tuples)
                    {
                        usleep(1000);

                        // Aim for one update per second
                        if (sleepcount++ > 500)
                        {
                            rankPerSecond = ((float)rankCountTuples + (float)count) / MAX(difftime(time(0), rankStartTime),1);
                            fprintf(stderr, "  Done %i in %i @ %f per second - Rank %i ETA (seconds): %f\n", (rankCountTuples + count), (int)(difftime(time(0), rankStartTime)), rankPerSecond, rank, ((float)(rankTotalTuples - (rankCountTuples + count)))/rankPerSecond);
                            sleepcount = 0;
                        }
                    }

                    // Wait for everything to finish
                    for (i = 0; i < num_threads; i++)
                    {
                        pthread_join(thread_data[i].thread, NULL);
                    }

                    rankCountTuples += tuples;
                }

                // Finished sector
                rankPerSecond = (float)rankCountTuples / MAX(difftime(time(0), rankStartTime),1);
                fprintf(stderr, "  Done %i in %i @ %f per second - ETA (seconds): %f\n", rankCountTuples, (int)(difftime(time(0), rankStartTime)), rankPerSecond, ((float)(rankTotalTuples - rankCountTuples))/rankPerSecond);

                PQclear(resPlaces);
            }
            if (rankTotalTuples-rankCountTuples < num_threads*20 && iSector < PQntuples(resSectors))
            {
                iSector = PQntuples(resSectors) - 1;
            }
        }
        // Finished rank
        fprintf(stderr, "\r  Done %i in %i @ %f per second - FINISHED                      \n\n", rankCountTuples, (int)(difftime(time(0), rankStartTime)), rankPerSecond);

        PQclear(resSectors);
    }

    if (writer)
    {
        nominatim_exportXMLEnd(writer);
    }
}

void *nominatim_indexThread(void * thread_data_in)
{
    struct index_thread_data * thread_data = (struct index_thread_data * )thread_data_in;
    struct export_data	querySet;

    PGresult   *res;

    const char *paramValues[1];
    int         paramLengths[1];
    int         paramFormats[1];
    uint32_t    paramPlaceID;
    uint32_t 	place_id;
    time_t 		updateStartTime;

    while (1)
    {
        pthread_mutex_lock( thread_data->count_mutex );
        if (*(thread_data->count) >= thread_data->tuples)
        {
            pthread_mutex_unlock( thread_data->count_mutex );
            break;
        }

        place_id = PGint32(*((uint32_t *)PQgetvalue(thread_data->res, *thread_data->count, 0)));
        (*thread_data->count)++;

        pthread_mutex_unlock( thread_data->count_mutex );

        if (verbose) fprintf(stderr, "  Processing place_id %d\n", place_id);

        updateStartTime = time(0);
	int done = 0;

        if (thread_data->writer)
        {
             nominatim_exportPlaceQueries(place_id, thread_data->conn, &querySet);
        }

	while(!done)
	{

	        paramPlaceID = PGint32(place_id);
        	paramValues[0] = (char *)&paramPlaceID;
	        paramLengths[0] = sizeof(paramPlaceID);
        	paramFormats[0] = 1;
	        res = PQexecPrepared(thread_data->conn, "index_placex", 1, paramValues, paramLengths, paramFormats, 1);
        	if (PQresultStatus(res) == PGRES_COMMAND_OK)
			done = 1;
		else
	        {
			if (strncmp(PQerrorMessage(thread_data->conn), "ERROR:  deadlock detected", 25))
			{
		            fprintf(stderr, "index_placex: UPDATE failed - deadlock, retrying\n");
		            PQclear(res);
                            sleep(rand() % 10);
			}
			else
			{
		            fprintf(stderr, "index_placex: UPDATE failed: %s", PQerrorMessage(thread_data->conn));
		            PQclear(res);
                            sleep(rand() % 10);
//		            exit(EXIT_FAILURE);
			}
		}
        }
        PQclear(res);
        if (difftime(time(0), updateStartTime) > 1) fprintf(stderr, "  Slow place_id %d\n", place_id);

        if (thread_data->writer)
        {
            nominatim_exportPlace(place_id, thread_data->conn, thread_data->writer, thread_data->writer_mutex, &querySet);
            nominatim_exportFreeQueries(&querySet);
        }
    }

    return NULL;
}