//
//  NBGeocoderMetadataHelper.m
//  libPhoneNumberiOS
//
//  Created by Rastaar Haghi on 6/12/20.
//  Copyright © 2020 ohtalk.me. All rights reserved.
//

#import "NBGeocoderMetadataHelper.h"

@implementation NBGeocoderMetadataHelper {
 @private
  NSString *databasePath;
  sqlite3 *DB;
  sqlite3_stmt *selectStatement;
}

- (instancetype)initWithCountryCode:(NSNumber *)countryCode withLanguage:(NSString *)language {
  self = [super init];

  self.countryCode = countryCode;
  self.language = language;
  // grab bundle of current pod instance
  NSBundle *bundle = [NSBundle bundleForClass:self.classForCoder];
  NSURL *bundleURL = [[bundle resourceURL] URLByAppendingPathComponent:@"Resources.bundle"];
  // create string for database directory
  NSString *databasePath = [NSString stringWithFormat:@"%@%@.db", bundleURL, self.language];
  self->databasePath = databasePath;

  // open the database position
  sqlite3_open([databasePath UTF8String], &self -> DB);

  // set up prepared statements for inserting entry and searching for entry
  sqlite3_prepare_v2(
      self->DB,
      [[NSString
          stringWithFormat:
              @"WITH RECURSIVE cnt(x) AS ( SELECT 1 UNION ALL SELECT x+1 FROM cnt LIMIT "
              @"length(?)), toSearch as (SELECT substr(?, 1, x) as indata FROM cnt) select "
              @"nationalnumber, description, length(nationalnumber) as natLength from "
              @"geocodingPairs%@ where NATIONALNUMBER in toSearch order by natLength desc limit 1",
              countryCode] UTF8String],
      -1, &self->selectStatement, NULL);
  return self;
}

- (void)dealloc {
  sqlite3_finalize(self->selectStatement);
  sqlite3_close_v2(self->DB);
}

// returns a select statement for finding description given a phone number
- (int)createSelectStatement:(NBPhoneNumber *)phoneNumber {
  int sqliteResultCode;
  @autoreleasepool {
    sqliteResultCode = sqlite3_reset(self->selectStatement);
    if (sqliteResultCode == SQLITE_OK) {
      const char *completePhoneNumber =
          [[NSString stringWithFormat:@"%@%@", phoneNumber.countryCode, phoneNumber.nationalNumber]
              UTF8String];
      sqlite3_bind_text(self->selectStatement, 1, completePhoneNumber, -1, SQLITE_TRANSIENT);
      sqlite3_bind_text(self->selectStatement, 2, completePhoneNumber, -1, SQLITE_TRANSIENT);
    } else {
      NSLog(@"The prepare statement result code was: %d", sqliteResultCode);
    }
  }
  return sqliteResultCode;
}

// returns YES if result found, NO if no results found
- (NSString *)searchPhoneNumberInDatabase:(NBPhoneNumber *)phoneNumber
                             withLanguage:(NSString *)language {
  @autoreleasepool {
    if (![phoneNumber.countryCode isEqualToNumber:self.countryCode]) {
      self.countryCode = phoneNumber.countryCode;
      sqlite3_prepare_v2(
          self->DB,
          [[NSString
              stringWithFormat:@"WITH RECURSIVE cnt(x) AS ( SELECT 1 UNION ALL SELECT x+1 FROM cnt "
                               @"LIMIT length(?)), toSearch as (SELECT substr(?, 1, x) as indata "
                               @"FROM cnt) select nationalnumber, description, "
                               @"length(nationalnumber) as natLength from geocodingPairs%@ where "
                               @"NATIONALNUMBER in toSearch order by natLength desc limit 1",
                               [self.countryCode stringValue]] UTF8String],
          -1, &self->selectStatement, NULL);
      NSLog(@"CHANGED COUNTRY CODE FOR SEARCHING");
    }

    if (![self.language isEqualToString:language]) {
      NSLog(@"CHANGED LANGUAGE CODE FOR SEARCHING");
      sqlite3_close(self->DB);
      self.language = language;
      // grab bundle of current pod instance
      NSBundle *bundle = [NSBundle bundleForClass:self.classForCoder];
      NSURL *bundleURL = [[bundle resourceURL] URLByAppendingPathComponent:@"Resources.bundle"];
      // create string for database directory
      NSString *databasePath = [NSString stringWithFormat:@"%@%@.db", bundleURL, self.language];
      self->databasePath = databasePath;
      // open the database position
      sqlite3_open([databasePath UTF8String], &self -> DB);
    }

    int sql_command_results;
    // if database hasn't been set, try opening and storing location
    if (self->DB == NULL) {
      sql_command_results =
          sqlite3_open_v2([self->databasePath UTF8String], &self -> DB, SQLITE_OPEN_READONLY, NULL);
      if (sql_command_results != SQLITE_OK) {
        NSLog(@"Failed to open db connection");
      } else {
        NSLog(@"Opened DB");
      }
    }
    sql_command_results = [self createSelectStatement:phoneNumber];

    if (sql_command_results != SQLITE_OK) {
      NSLog(@"Error with preparing statement");
      return @"";
    }
    // only get the first row found
    int step = sqlite3_step(self->selectStatement);
    if (step == SQLITE_ROW) {
      NSString *description = @((const char *)sqlite3_column_text(self->selectStatement, 1));
      self.regionDescription = description;
      return description;
    }
  }
  return @"";
}

@end