1. 1
2. 2
3. 3
4. 4
5. 5
6. 6
7. 7
8. 8
9. 9
10. 10
11. 11
12. 12
13. 13
14. 14
15. 15
16. 16
17. 17
18. 18
19. 19
20. 20
21. 21
22. 22
23. 23
24. 24
25. 25
26. 26
27. 27
28. 28
29. 29
30. 30
31. 31
32. 32
33. 33
34. 34
35. 35
36. 36
37. 37
38. 38
39. 39
40. 40
41. 41
42. 42
43. 43
44. 44
45. 45
46. 46
47. 47
48. 48
49. 49
50. 50
51. 51
52. 52
53. 53
54. 54
55. 55
56. 56
57. 57
58. 58
59. 59
60. 60
61. 61
62. 62
63. 63
64. 64
65. 65
66. 66
67. 67
68. 68
69. 69
70. 70
71. 71
72. 72
73. 73
74. 74
75. 75
76. 76
77. 77
78. 78
79. 79
80. 80
81. 81
82. 82
83. 83
84. 84
85. 85
86. 86
87. 87
88. 88
89. 89
90. 90
91. 91
92. 92
93. 93
94. 94
95. 95
96. 96
97. 97
98. 98
99. 99
100. 100
101. 101
102. 102
103. 103
104. 104
105. 105
106. 106
107. 107
108. 108
109. 109
110. 110

// SPDX-FileCopyrightText: 2024 Shota FUJI <pockawoooh@gmail.com>
//
// SPDX-License-Identifier: Apache-2.0

import { SEPARATOR } from "../../deps/deno.land/std/path/mod.ts";

import type {
	DirectoryReader,
	FileReader,
	FileSystemReader,
	RootDirectoryReader,
} from "./interface.ts";

export class DenoFsReader implements FileSystemReader {
	#root: string;

	constructor(rootDirectory: string | URL) {
		this.#root = typeof rootDirectory === "string"
			? rootDirectory
			: rootDirectory.pathname;

		// Append trailing slash for easy path resolving
		if (!(/[\\/]$/.test(this.#root))) {
			this.#root += SEPARATOR;
		}
	}

	#resolve = (path: readonly string[]): string => {
		let normalized: string[] = [];

		for (const segment of path) {
			switch (segment) {
				case ".":
					break;
				case "..":
					// TODO: Abort for above the root traversal.
					normalized = normalized.slice(0, -1);
					break;
				default:
					normalized.push(segment);
					break;
			}
		}

		return this.#root + normalized.join(SEPARATOR);
	};

	#fromDirEntry = (
		dirEntry: Deno.DirEntry,
		parent: DirectoryReader | RootDirectoryReader,
	): FileReader | DirectoryReader => {
		const { name, isSymlink, isFile } = dirEntry;

		const path = parent.type === "root" ? [name] : [...parent.path, name];

		if (isSymlink) {
			// TODO: Log warning and skip.
			throw new Error("DenoFsReader does not support reading symlinks.");
		}

		if (isFile) {
			return {
				type: "file",
				name,
				path,
				parent,
				read: () => {
					return Deno.readFile(this.#resolve(path));
				},
			};
		}

		const dir: DirectoryReader = {
			type: "directory",
			name,
			path,
			parent,
			read: async () => {
				const converted: Array<FileReader | DirectoryReader> = [];

				for await (const entry of Deno.readDir(this.#resolve(path))) {
					converted.push(this.#fromDirEntry(entry, dir));
				}

				return converted;
			},
		};

		return dir;
	};

	async getRootDirectory(): Promise<RootDirectoryReader> {
		await Deno.permissions.request({ name: "read", path: this.#root });

		const root: RootDirectoryReader = {
			type: "root",
			read: async () => {
				const converted: Array<FileReader | DirectoryReader> = [];

				for await (const entry of Deno.readDir(this.#root)) {
					converted.push(this.#fromDirEntry(entry, root));
				}

				return converted;
			},
		};

		return root;
	}
}