#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <time.h>
#include <limits.h>
#include <sys/stat.h>
#include <errno.h>
#include <unistd.h>

#include "context.h"
#include "package.h"

int db_context_free(struct syrep_db_context* c) {
    if (c) {

        if (c->db_id_meta)
            c->db_id_meta->close(c->db_id_meta, 0);
        
        if (c->db_md_name)
            c->db_md_name->close(c->db_md_name, 0);

        if (c->db_name_md)
            c->db_name_md->close(c->db_name_md, 0);

        if (c->db_md_lastname)
            c->db_md_lastname->close(c->db_md_lastname, 0);

        if (c->db_name_lastmd)
            c->db_name_lastmd->close(c->db_name_lastmd, 0);
        
        if (c->db_version_timestamp)
            c->db_version_timestamp->close(c->db_version_timestamp, 0);

        if (c->package)
            package_remove(c->package);

        if (c->origin)
            free(c->origin);
        
        free(c);
    }

    return 0;
}


static DB* open_db(const char*path, int dup) {
    int ret;
    DB* db;

    if ((ret = db_create(&db, NULL, 0))) {
        fprintf(stderr, "db_create: %s\n", db_strerror(ret));
        return NULL;
    }

    if (dup)
        db->set_flags(db, DB_DUPSORT);

    //db->set_pagesize(db, 4096*8);

    if ((ret = db->open(db, NULL, path, NULL, DB_BTREE, DB_CREATE, 0664))) {
        db->err(db, ret, "open(%s)", path);
        db->close(db, 0);
        return NULL;
    }

    return db;
}

struct syrep_db_context* db_context_open(const char *filename) {
    struct syrep_db_context *c = NULL;
    const char* path;
    FILE *f;

    if (!(c = malloc(sizeof(struct syrep_db_context))))
        goto fail;

    memset(c, 0, sizeof(struct syrep_db_context));

    if (!(c->package = package_open(filename)))
        goto fail;

    path = package_get_item(c->package, "timestamp", 1);
    if ((f = fopen(path, "r"))) {
        if (fscanf(f, "%i", &c->timestamp) != 1)
            c->timestamp = 0;
        fclose(f);
    }

    if (!c->timestamp)
        c->timestamp = time(NULL);

    path = package_get_item(c->package, "version", 1);
    if ((f = fopen(path, "r"))) {
        if (fscanf(f, "%u", &c->version) != 1)
            c->version = 0;
        fclose(f);
    }
    
    path = package_get_item(c->package, "origin", 1);
    if ((f = fopen(path, "r"))) {
        char hn[256];
        if (fgets(hn, sizeof(hn), f)) {
            char *nl;
            
            if ((nl = strchr(hn, '\n')))
                *nl = 0;
                
            if (hn[0])
                c->origin = strdup(hn);
        }
        
        fclose(f);
    } else
        c->version = 0;

    if (!c->origin) {
        char hn[256];
        if (gethostname(hn, sizeof(hn)) < 0)
            goto fail;

        c->origin = strdup(hn);
    }

    /* Creating database id_meta */
    if (!(c->db_id_meta = open_db(package_get_item(c->package, "id_meta", 1), 0)))
        goto fail;

    /* Creating database md_name */
    if (!(c->db_md_name = open_db(package_get_item(c->package, "md_name", 1), 1)))
        goto fail;

    /* Creating database name_md */
    if (!(c->db_name_md = open_db(package_get_item(c->package, "name_md", 1), 1)))
        goto fail;

    /* Creating database name_lastmd */
    if (!(c->db_name_lastmd = open_db(package_get_item(c->package, "name_lastmd", 1), 0)))
        goto fail;

    /* Creating database md_lastname */
    if (!(c->db_md_lastname = open_db(package_get_item(c->package, "md_lastname", 1), 0)))
        goto fail;
    
    /* Creating database version_timestamp */
    if (!(c->db_version_timestamp = open_db(package_get_item(c->package, "version_timestamp", 1), 0)))
        goto fail;
    
    return c;

    
fail:
    db_context_free(c);
    
    return NULL;
}

int db_context_save(struct syrep_db_context *c, const char *filename) {
    FILE *f;
    assert(c && c->package);

    if (c->db_id_meta)
        c->db_id_meta->sync(c->db_id_meta, 0);
        
    if (c->db_md_name)
        c->db_md_name->sync(c->db_md_name, 0);

    if (c->db_name_md)
        c->db_name_md->sync(c->db_name_md, 0);

    if (c->db_md_lastname)
        c->db_md_lastname->sync(c->db_md_lastname, 0);

    if (c->db_name_lastmd)
        c->db_name_lastmd->sync(c->db_name_lastmd, 0);

    if (c->db_version_timestamp)
        c->db_version_timestamp->sync(c->db_version_timestamp, 0);
        
    if (!(f = fopen(package_get_item(c->package, "timestamp", 1), "w+")))
        return -1;

    fprintf(f, "%i\n", c->timestamp);
    fclose(f);

    if (!(f = fopen(package_get_item(c->package, "version", 1), "w+")))
        return -1;

    fprintf(f, "%u\n", c->version);
    fclose(f);

    if (!(f = fopen(package_get_item(c->package, "origin", 1), "w+")))
        return -1;

    fprintf(f, "%s\n", c->origin);
    fclose(f);
    
    return package_save(c->package, filename);
}