/* <https://gist.github.com/enile8/2424514> */
#define _POSIX_C_SOURCE 200809L /* strtok_r, strndup */
#include <string.h>
#include <assert.h>             /* assert */
#include <sqlite3.h>
#include <stdio.h>              /* size_t */
#include <stdlib.h>             /* free */

#include "data.h"
#include "io.h"
#include "i18n.h"
#include "unused.h"

#define FINISH_UP() \
    rc = sqlite3_reset(stmt); \
    if (SQLITE_OK != rc) { \
        fprintf(stderr, string_errmsg_reset, sqlite3_errmsg(db)); \
    } \
    rc = sqlite3_clear_bindings(stmt); \
    if (SQLITE_OK != rc) { \
        fprintf(stderr, string_errmsg_clear, sqlite3_errmsg(db)); \
    } \
    return sqlite3_finalize(stmt)

static const char string_errmsg_bind[] = _("Error binding parameter: %s\n");
static const char string_errmsg_clear[] = _("Error clearing bindings: %s\n");
static const char string_errmsg_delete[] = _("Error deleting data: %s\n");
static const char string_errmsg_insert[] = _("Error inserting data: %s\n");
static const char string_errmsg_prepare[] = _("Error preparing data: %s\n");
static const char string_errmsg_readfile[] = _("Error reading file: %s\n");
static const char string_errmsg_reset[] = _("Error resetting statement: %s\n");
static const char string_errmsg_update[] = _("Error updating data: %s\n");
static const char string_null_msg[] = _("(null)\n");
static const char string_sqlite_version[] = _("SQLite version: %s\n");
static const char string_unmatched_comment[] = _("Unmatched comment: %d\n");

int run_script_callback(void *NotUsed, int argc, char **argv, char **azColName) {
    int i;
    UNUSED(NotUsed);
    for (i = 0; i < argc; i++) {
        printf(" => %s = %s\n", azColName[i], (argv[i] ? argv[i] : string_null_msg));
    }
    return SQLITE_OK;
}

int run_script(sqlite3 * db, int (*callback)(void *, int, char **, char **), const char *script_filename) {
    int j, rc, incomment;
    char *statements, *zErrMsg;
    char *str1, *saveptr1, *token;
    zErrMsg = 0;
    if (!(statements = file_read(script_filename, NULL))) {
        fprintf(stderr, string_errmsg_readfile, script_filename);
        return -1;
    }
    incomment = 0;
    for (j = 1, str1 = statements;; j++, str1 = NULL) {
        token = strtok_r(str1, "\n", &saveptr1);
        if (token == NULL)
            break;
        if (strlen(token) > 2 && token[0] == '-' && token[1] == '-')
            continue;           /* Comment line; TODO multiline comment */
        if (strstr(token, "/*")) {
            incomment = 1;
        }
        if (strstr(token, "*/")) {
            if (!incomment) {
                fprintf(stderr, string_unmatched_comment, j);
            }
            incomment = 0;
        }
        if (incomment)
            continue;
        printf("%d: %s\n", j, token);
        rc = sqlite3_exec(db, token, callback, 0, &zErrMsg);
        if (SQLITE_OK != rc) {
            fprintf(stderr, "!! SQL error: %s\n", zErrMsg);
            sqlite3_free(zErrMsg);
            break;
        }
    }
    free(statements);
    fprintf(stderr, "Bye!\n");
    return SQLITE_OK;
}

int run_one(sqlite3 * db, int (*callback)(void *, int, char **, char **), const char *query) {
    int rc = SQLITE_ERROR;
    char *zErrMsg = NULL;
    if (SQLITE_OK != (rc = sqlite3_exec(db, query, callback, 0, &zErrMsg))) {
        fprintf(stderr, "!! SQL error: %s\n", zErrMsg);
        sqlite3_free(zErrMsg);
    }
    return rc;
}

int insert_new_definition(sqlite3 * db, const char *channel, const char *name, const char *word, const char *definition) {
    const char insert_stmt[] = "insert into dictionarydb (date_added , channel , added_by, word , definition ) values (datetime('now'), ?, ?, ?, ?)";
    int n, rc;
    sqlite3_stmt *stmt = NULL;

    rc = sqlite3_prepare_v2(db, insert_stmt, -1, &stmt, 0);
    if (SQLITE_OK != rc) {
        fprintf(stderr, string_errmsg_prepare, sqlite3_errmsg(db));
        goto _out;
    }

    n = 0;
#define S(x) \
    rc = sqlite3_bind_text(stmt, ++n, x, (int)strnlen(x, 4096), SQLITE_STATIC); \
    if (SQLITE_OK != rc) { \
        fprintf(stderr, string_errmsg_bind, sqlite3_errmsg(db)); \
        goto _out; \
    }
    S(channel);
    S(name);
    S(word);
    S(definition);
#undef S

    if (SQLITE_DONE != (rc = sqlite3_step(stmt))) {
        fprintf(stderr, string_errmsg_insert, sqlite3_errmsg(db));
    }
 _out:
    FINISH_UP();
}

int delete_from_table_by_rowid(sqlite3 * db, int rowid) {
    int rc;
    const char insert_stmt[] = "delete from dictionarydb where rowid = ?";
    sqlite3_stmt *stmt = NULL;

    rc = sqlite3_prepare_v2(db, insert_stmt, -1, &stmt, 0);
    if (SQLITE_OK != rc) {
        fprintf(stderr, string_errmsg_prepare, sqlite3_errmsg(db));
        goto _out;
    }

    rc = sqlite3_bind_int(stmt, 1, rowid);
    if (SQLITE_OK != rc) {
        fprintf(stderr, string_errmsg_bind, sqlite3_errmsg(db));
        goto _out;
    }
    if (SQLITE_DONE != (rc = sqlite3_step(stmt))) {
        fprintf(stderr, string_errmsg_delete, sqlite3_errmsg(db));
    }
 _out:
    FINISH_UP();
}

int sqlite_version(sqlite3 * db) {
    int rc;
    sqlite3_stmt *stmt = NULL;
    rc = sqlite3_prepare_v2(db, "SELECT SQLITE_VERSION()", -1, &stmt, 0);
    if (SQLITE_OK != rc) {
        fprintf(stderr, string_errmsg_prepare, sqlite3_errmsg(db));
        goto _out;
    }
    while (SQLITE_ROW == (rc = sqlite3_step(stmt))) {
        printf(string_sqlite_version, sqlite3_column_text(stmt, 0));
    }
    if (SQLITE_DONE != rc) {
        fprintf(stderr, string_errmsg_update, sqlite3_errmsg(db));
    }
 _out:
    FINISH_UP();
}

/*
 * table_exists(tbl) =>
 * 0 => table does not exist
 * 1 => table exists
 */
int table_exists(sqlite3 * db, int (*callback)(void *, int, char **, char **), const char *table) {
    int ret, rc;
    char buf[BUFSIZ];
    const char table_exists_query[] = "SELECT name FROM sqlite_master WHERE type = 'table' AND name = '%s'";
    char *zErrMsg;

    ret = 0;
    memset(buf, 0, BUFSIZ);
    sprintf(buf, table_exists_query, table);
    rc = sqlite3_exec(db, buf, callback, 0, &zErrMsg);
    if (SQLITE_OK == rc) {
        ret = 1;
    }

    return ret;
}