KMvuXwTh

1import Foundation
2import RealmSwift
3import SQLite3
4
5class ExportDB {
6    
7    private var realm: Realm
8    private var db: OpaquePointer?
9    
10    internal let SQLITE_STATIC = unsafeBitCast(0, to: sqlite3_destructor_type.self)
11    internal let SQLITE_TRANSIENT = unsafeBitCast(-1, to: sqlite3_destructor_type.self)
12    
13    init(realm: Realm) {
14        self.realm = realm
15    }
16    
17    public func export() {
18        let fileURL = try! FileManager.default.url(for: .cachesDirectory, in: .userDomainMask, appropriateFor: nil, create: false)
19            .appendingPathComponent("temp.sqlite")
20        
21        do { try FileManager.default.removeItem(at: fileURL) }
22        catch { debugPrint(#function, error.localizedDescription) }
23        
24        if sqlite3_open(fileURL.path, &db) != SQLITE_OK {
25            print("error opening database")
26        }
27        
28        let start = CFAbsoluteTimeGetCurrent()
29        realm.schema.objectSchema.forEach { (schema) in
30            exportTable(schema: schema)
31        }
32        let diff = CFAbsoluteTimeGetCurrent() - start
33        print("Took \(diff) seconds to Create Table")
34        
35        
36        let start1 = CFAbsoluteTimeGetCurrent()
37        realm.schema.objectSchema.forEach { (schema) in
38            fillTable(schema: schema)
39        }
40        let diff1 = CFAbsoluteTimeGetCurrent() - start1
41        print("Took \(diff1) seconds to Export Values")
42        
43    }
44    
45    private func getSQLType(_ property: (Property)) -> String {
46        switch property.type {
47        case .bool: return "BOOL"
48        case .int: return "INTEGER"
49        case .string, .date: return "TEXT"
50        case .data: return "BLOB"
51        case .float, .double: return "REAL"
52        default: return "TEXT"
53        }
54    }
55    
56    private func exportTable(schema: ObjectSchema) {
57        var sql = "CREATE TABLE IF NOT EXISTS \(schema.className) ("
58        let primaryKeyProperty = schema.primaryKeyProperty
59        schema.properties.forEach { (property) in
60            if property.type == .linkingObjects || property.isArray || property.type == .object || property.type == .data { return }
61            
62            sql.append("\'\(property.name)\'")
63            
64            sql.append(" \(getSQLType(property))")
65            
66            if property == primaryKeyProperty { sql.append(" PRIMARY KEY") }
67            
68            if !property.isOptional { sql.append(" NOT NULL") }
69            
70            sql.append(", ")
71        }
72        
73        sql.removeLast()
74        sql.removeLast()
75        sql.append(")")
76        
77        if sqlite3_exec(db, sql, nil, nil, nil) != SQLITE_OK {
78            let errmsg = String(cString: sqlite3_errmsg(db)!)
79            debugPrint(schema.className, "error creating table: \(errmsg)")
80        }
81    }
82    
83    private func fillTable(schema: ObjectSchema) {
84        if let classObject = NSClassFromString("ChecklistFacil.\(schema.className)") {
85            let objects = realm.objects(classObject as! Object.Type)
86            if objects.isEmpty { return }
87            
88            var sql = "INSERT INTO \(schema.className) VALUES ("
89            
90            objects.forEach { (object) in
91                schema.properties.forEach { (property) in
92                    if property.type == .linkingObjects || property.isArray || property.type == .object || property.type == .data { return }
93                    
94                    if let value = object.value(forKey: property.name) {
95                        if getSQLType(property) == "TEXT" {
96                            if property.type == .string {
97                                var textValue = String(format: "%@", value as! CVarArg)
98                                textValue = textValue.replacingOccurrences(of: "\"", with: "\u{0022}")
99                                textValue = textValue.replacingOccurrences(of: "\'", with: "\u{FF07}")
100                                sql.append("\'\(textValue)\', ")
101                            } else { sql.append("\'\(value)\', ") }
102                            
103                        } else { sql.append("\(value), ") }
104                    
105                    } else { sql.append("NULL, ") }
106                }
107                
108                sql.removeLast()
109                sql.removeLast()
110                sql.append("),\n(")
111            }
112            
113            sql.removeLast()
114            sql.removeLast()
115            sql.removeLast()
116            
117            if sqlite3_exec(db, sql, nil, nil, nil) != SQLITE_OK {
118                let errmsg = String(cString: sqlite3_errmsg(db)!)
119                debugPrint(schema.className, "error inserting in table: \(errmsg)")
120            }
121        }
122    }
123}