import yargs from "yargs/yargs";
import path from "path";

import { hideBin } from "yargs/helpers";

const args = yargs(hideBin(process.argv))
    .option("package", {
        type: "string",
        describe: "The full or relative path to the package.json file",
        require: true
    })
    .option("format", {
        choices: ["tree", "csv"],
        demandOption: true,
        default: "tree"
    })
    .option("filter", {
        choices: ["none", "oracle"],
        demandOption: true,
        default: "none"
    })
    .help()
    .argv;


interface Dictionary<T> {
    [index: string]: T
}

interface Package {
    dependencies: Dictionary<string>;
    devDependencies?: Dictionary<string>;
}

type PackageLockDependencies = Dictionary<{
    version: string;
    dev: boolean;
    requires?: Dictionary<string>;
    dependencies?: PackageLockDependencies;
}>

interface PackageLock {
    dependencies: PackageLockDependencies;
}



type Tree<T> = Leaf<T> | Node<T>;

type Node<T> = {
    type: "node";
    value: T;
    children: Tree<T>[];
}

type Leaf<T> = {
    type: "leaf";
    value: T;
}

type PackageLockTree = Tree<{ name: string, version: string, dev: boolean }>;



const constructDepTree = (packageName: string, context: PackageLockDependencies, stack: string[] = []): PackageLockTree => {
    const dependency = context[packageName];
    const value = { name: packageName, version: dependency.version, dev: dependency.dev };
    if (!dependency.requires) {
        return { type: "leaf", value };
    }
    return {
        type: "node",
        value,
        children: Object.keys(dependency.requires).filter(k => stack.every(s => s !== k))
            .map(requiredDepName => constructDepTree(requiredDepName, { ...context, ...dependency.dependencies }, [...stack, packageName]))
    };
}

const displayDepTree = (format: (node: PackageLockTree, parents: string[]) => string) =>
    (filter: (node: PackageLockTree, parents: string[]) => boolean) =>
        (tree: PackageLockTree) => {
            const iter = (tree: PackageLockTree, stack: string[] = []) => {
                if (filter(tree, stack)) {
                    console.log(format(tree, stack));
                }
                if (tree.type === "node") {
                    tree.children.forEach(t => iter(t, [...stack, `${tree.value.name}@${tree.value.version}`]))
                }
            }
            iter(tree);
        }


Promise.all<Package, PackageLock>([
    import(args.package),
    import(`${path.dirname(args.package)}/package-lock.json`)
])
    .then(([json, jsonLock]) => {
        const dependencyTree = Object.keys(json.dependencies)
            .concat(Object.keys(json.devDependencies ?? {}))
            .map(depName => constructDepTree(depName, jsonLock.dependencies));
        if (args.format === "csv") {
            console.log("name,version,root,parent,type");
        }
        const format = args.format === "tree"
            ? (node: PackageLockTree, parents: string[]) => `${"  ".repeat(parents.length)}${node.value.name}@${node.value.version}${node.value.dev ? " (dev)" : ""}`
            : (node: PackageLockTree, parents: string[]) => `${node.value.name},${node.value.version},${parents[0] ?? ""},${parents[parents.length - 1] ?? ""},${node.value.dev ? "devDependency" : "dependency"}`;
        const filter = args.filter === "oracle"
            ? (node: PackageLockTree, parents: string[]) => (parents.length === 0 && !node.value.name.startsWith("@os")) || (!node.value.name.startsWith("@o") && parents.length > 1 && parents.every(p => p.startsWith("@os")))
            : (node: PackageLockTree, parents: string[]) => true;
        const display = displayDepTree(format)(filter);
        dependencyTree.forEach(t => display(t));
    })
    .catch(reson => {
        console.error(reson);
    });