Added an "migrate-possible" command

src/commands/migrate_possible.ts

@@ -0,0 +1,36 @@
+import Subcommand from "./subcommand.js";
+import {Command} from "commander";
+import ModManager from "../mod-manager.js";
+import Mods from "../mods/mods.js";
+import MinecraftUtils from "../util/minecraft_utils.js";
+import PrintUtils from "../util/print_utils.js";
+
+export default class MigratePossibleCommand implements Subcommand {
+    registerCommand(program: Command): void {
+        program.command("migrate-possible")
+            .description("Reports whether it is possible to upgrade to the provided Minecraft version")
+            .argument("[version]", "The Minecraft version to try and migrate to")
+            .action((version) => {
+                ModManager.execute(async () => {
+                        // If no version is provided, prompt user for one
+                        if (version === "" || version == undefined) {
+                            version = await MinecraftUtils.getMinecraftVersionFromInput("What Minecraft version would you like to migrate to?");
+                        }
+
+                        // If version is valid, check if migration is possible
+                        if (await MinecraftUtils.isValidVersion(version)) {
+                            const possible = await Mods.isMigratePossible(version);
+
+                            if (possible) {
+                                PrintUtils.success(`It is possible to migrate to version ${version}`)
+                            } else {
+                                PrintUtils.error(`It is not possible to migrate to version ${version}`)
+                            }
+                        } else {
+                            PrintUtils.error(`${version} is not a valid Minecraft version`);
+                        }
+                    }
+                )
+            })
+    }
+}

src/mod-manager.ts

@@ -12,6 +12,7 @@ import UninstallCommand from "./commands/uninstall_command.js";
 import EssentialCommand from "./commands/essential_command.js";
 import {readFileSync, unlinkSync} from "fs";
 import UpgradeCommand from "./commands/upgrade_command.js";
+import MigratePossibleCommand from "./commands/migrate_possible.js";
 
 
 export default class ModManager {
@@ -25,7 +26,8 @@ export default class ModManager {
         new ListCommand(),
         new UninstallCommand(),
         new EssentialCommand(),
-        new UpgradeCommand()
+        new UpgradeCommand(),
+        new MigratePossibleCommand()
     ];
 
     static FilePaths = class {

src/mods/mods.ts

@@ -207,4 +207,35 @@ export default class Mods {
 
         return source
     }
+
+    static async isMigratePossible(version: string): Promise<boolean> {
+        const mods = this.getTrackedMods();
+
+        let availableList = [];
+
+        // For every tracked mod
+        for (let mod of mods) {
+            // Get the latest version for each mod on the provided minecraft version
+            const spinner = new PrintUtils.Spinner(`Checking ${mod.name}...`);
+            spinner.start();
+
+            const source = this.getSourceFromName(mod.source);
+            try {
+                await source.getLatestVersion(mod.id, version)
+                // Report and record that this mod is available
+                spinner.succeed(`${mod.name} is available on Minecraft ${version}`)
+                availableList.push(true)
+            } catch (e) {
+                // Report and record that this mod is not available
+                spinner.error(`${mod.name} is not available on Minecraft ${version}`)
+                availableList.push(false);
+            }
+        }
+
+        // Filter out all the true's from the list
+        availableList = availableList.filter(available => !available)
+
+        // If the array is empty, all the mods reported as available, and a migration is possible
+        return Util.isArrayEmpty(availableList);
+    }
 }

src/util/initialiser.ts

@@ -2,9 +2,7 @@ import {existsSync, mkdirSync, writeFileSync} from "fs";
 import path from "path";
 import PrintUtils from "./print_utils.js";
 import ModManager from "../mod-manager.js";
-import inquirer from "inquirer";
 import MinecraftUtils from "./minecraft_utils.js";
-import MinecraftVersionError from "../errors/minecraft_version_error.js";
 
 export default class Initialiser {
     public static async initialise(): Promise<void> {
@@ -13,7 +11,7 @@ export default class Initialiser {
                 const success: boolean = this.setupFolderStructure();
 
                 if (success) {
-                    const version = await this.getMinecraftVersionFromInput();
+                    const version = await MinecraftUtils.getMinecraftVersionFromInput("What Minecraft version is your server running?");
                     await MinecraftUtils.updateCurrentMinecraftVersion(version)
 
                     PrintUtils.success("Sucessfully initialised Mod Manager!");
@@ -56,30 +54,4 @@ export default class Initialiser {
             return false;
         }
     }
-
-    private static async getMinecraftVersionFromInput() {
-        let isVersionValid = false;
-
-        let version: string | undefined = undefined;
-        while (!isVersionValid) {
-            const answer = await inquirer.prompt([{
-                type: "input",
-                name: "minecraft_version",
-                message: "What version of Minecraft is the server running?"
-            }])
-            version = answer.minecraft_version;
-
-            if (await MinecraftUtils.isValidVersion(version)) {
-                isVersionValid = true;
-            } else {
-                PrintUtils.error(`${version} is not a valid Minecraft version for a Fabric server. Please try again`);
-            }
-        }
-
-        if (version == undefined) {
-            throw new MinecraftVersionError("Escaped version input without a valid version")
-        }
-
-        return version;
-    }
 }

src/util/minecraft_utils.ts

@@ -2,6 +2,8 @@ import {readFileSync, writeFileSync} from "fs";
 import axios from "axios";
 import ModManager from "../mod-manager.js";
 import MinecraftVersionError from "../errors/minecraft_version_error.js";
+import inquirer from "inquirer";
+import PrintUtils from "./print_utils.js";
 
 export default class MinecraftUtils {
     static async getCurrentMinecraftVersion(): Promise<string> {
@@ -34,5 +36,31 @@ export default class MinecraftUtils {
         }
     }
 
+    public static async getMinecraftVersionFromInput(question: string) {
+        let isVersionValid = false;
+
+        let version: string | undefined = undefined;
+        while (!isVersionValid) {
+            const answer = await inquirer.prompt([{
+                type: "input",
+                name: "minecraft_version",
+                message: question
+            }])
+            version = answer.minecraft_version;
+
+            if (await MinecraftUtils.isValidVersion(version)) {
+                isVersionValid = true;
+            } else {
+                PrintUtils.error(`${version} is not a valid Minecraft version for a Fabric server. Please try again`);
+            }
+        }
+
+        if (version == undefined) {
+            throw new MinecraftVersionError("Escaped version input without a valid version")
+        }
+
+        return version;
+    }
+
 }