summaryrefslogtreecommitdiff
path: root/src/SMAPI/Framework/Serialisation/JsonHelper.cs
blob: f66f9dfb0aa26d9552b5071c16d51e1c446587fd (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
using System;
using System.Collections.Generic;
using System.IO;
using Microsoft.Xna.Framework.Input;
using Newtonsoft.Json;

namespace StardewModdingAPI.Framework.Serialisation
{
    /// <summary>Encapsulates SMAPI's JSON file parsing.</summary>
    internal class JsonHelper
    {
        /*********
        ** Accessors
        *********/
        /// <summary>The JSON settings to use when serialising and deserialising files.</summary>
        private readonly JsonSerializerSettings JsonSettings = new JsonSerializerSettings
        {
            Formatting = Formatting.Indented,
            ObjectCreationHandling = ObjectCreationHandling.Replace, // avoid issue where default ICollection<T> values are duplicated each time the config is loaded
            Converters = new List<JsonConverter>
            {
                // enums
                new StringEnumConverter<Buttons>(),
                new StringEnumConverter<Keys>(),
                new StringEnumConverter<SButton>(),

                // crossplatform compatibility
                new ColorConverter(),
                new PointConverter(),
                new RectangleConverter()
            }
        };


        /*********
        ** Public methods
        *********/
        /// <summary>Read a JSON file.</summary>
        /// <typeparam name="TModel">The model type.</typeparam>
        /// <param name="fullPath">The absolete file path.</param>
        /// <returns>Returns the deserialised model, or <c>null</c> if the file doesn't exist or is empty.</returns>
        /// <exception cref="InvalidOperationException">The given path is empty or invalid.</exception>
        public TModel ReadJsonFile<TModel>(string fullPath)
            where TModel : class
        {
            // validate
            if (string.IsNullOrWhiteSpace(fullPath))
                throw new ArgumentException("The file path is empty or invalid.", nameof(fullPath));

            // read file
            string json;
            try
            {
                json = File.ReadAllText(fullPath);
            }
            catch (Exception ex) when (ex is DirectoryNotFoundException || ex is FileNotFoundException)
            {
                return null;
            }

            // deserialise model
            try
            {
                return this.Deserialise<TModel>(json);
            }
            catch (JsonReaderException ex)
            {
                string error = $"The file at {fullPath} doesn't seem to be valid JSON.";
                if (json.Contains("“") || json.Contains("”"))
                    error += " Found curly quotes in the text; note that only straight quotes are allowed in JSON.";
                error += $"\nTechnical details: {ex.Message}";
                throw new JsonReaderException(error);
            }
        }

        /// <summary>Save to a JSON file.</summary>
        /// <typeparam name="TModel">The model type.</typeparam>
        /// <param name="fullPath">The absolete file path.</param>
        /// <param name="model">The model to save.</param>
        /// <exception cref="InvalidOperationException">The given path is empty or invalid.</exception>
        public void WriteJsonFile<TModel>(string fullPath, TModel model)
            where TModel : class
        {
            // validate
            if (string.IsNullOrWhiteSpace(fullPath))
                throw new ArgumentException("The file path is empty or invalid.", nameof(fullPath));

            // create directory if needed
            string dir = Path.GetDirectoryName(fullPath);
            if (dir == null)
                throw new ArgumentException("The file path is invalid.", nameof(fullPath));
            if (!Directory.Exists(dir))
                Directory.CreateDirectory(dir);

            // write file
            string json = JsonConvert.SerializeObject(model, this.JsonSettings);
            File.WriteAllText(fullPath, json);
        }


        /*********
        ** Private methods
        *********/
        /// <summary>Deserialize JSON text if possible.</summary>
        /// <typeparam name="TModel">The model type.</typeparam>
        /// <param name="json">The raw JSON text.</param>
        private TModel Deserialise<TModel>(string json)
        {
            try
            {
                return JsonConvert.DeserializeObject<TModel>(json, this.JsonSettings);
            }
            catch (JsonReaderException)
            {
                // try replacing curly quotes
                if (json.Contains("“") || json.Contains("”"))
                {
                    try
                    {
                        return JsonConvert.DeserializeObject<TModel>(json.Replace('“', '"').Replace('”', '"'), this.JsonSettings);
                    }
                    catch { /* rethrow original error */ }
                }

                throw;
            }
        }
    }
}