import { MergeStrategy, Rule, SchematicContext, Tree, apply, chain, mergeWith, strings, template, url } from '@angular-devkit/schematics';
import { NodePackageInstallTask } from '@angular-devkit/schematics/tasks';
import { Schema } from './schema';
import { Observable } from 'rxjs';
import * as fs from 'fs';

interface PackageJson {
    scripts: Record<string, string>;
    dependencies: Record<string, string>;
    devDependencies: Record<string, string>;
}

// You don't have to export the function as default. You can also have more than one rule factory per file.
export function newProject(options: Schema): Rule {

    if (fs.existsSync(options.name)) {
        throw new Error(`A folder named "${options.name}" already exists.`);
    }

    return (tree: Tree, context: SchematicContext) => {
        const rule = chain([
            mergeWith(apply(url('./files'), [
                template({ ...options, ...strings }),
            ]), MergeStrategy.Default),
            addPackageJsonDependency(options.name, '@angular-architects/module-federation', false, '15.0.3'),
            addPackageJsonDependency(options.name, '@angular/animations', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/cdk', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/common', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/compiler', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/core', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/elements', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/forms', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/platform-browser', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/platform-browser-dynamic', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@angular/router', false, '15.1.5'),
            addPackageJsonDependency(options.name, '@module-federation/typescript', false, "2.3.0"),
            addPackageJsonDependency(options.name, 'rxjs', false, '7.8.1'),
            addPackageJsonDependency(options.name, 'tslib', false, '2.5.0'),
            addPackageJsonDependency(options.name, 'zone.js', false, '0.12.0'),
            addPackageJsonDependency(options.name, "@unilygrouplimited/manifest-factory", true, "1.0.2"),
            addPackageJsonDependency(options.name, "@unilygrouplimited/sas-plugin", true, "1.0.0"),
            addPackageJsonDependency(options.name, '@unilygrouplimited/remote-service', false, "1.0.1"),
            addPackageJsonDependency(options.name, '@angular-devkit/build-angular', true, '15.1.6'),
            addPackageJsonDependency(options.name, '@angular-eslint/builder', true, '15.2.0'),
            addPackageJsonDependency(options.name, '@angular-eslint/eslint-plugin', true, '15.2.0'),
            addPackageJsonDependency(options.name, '@angular-eslint/eslint-plugin-template', true, '15.2.0'),
            addPackageJsonDependency(options.name, '@angular-eslint/schematics', true, '15.2.0'),
            addPackageJsonDependency(options.name, '@angular-eslint/template-parser', true, '15.2.0'),
            addPackageJsonDependency(options.name, '@angular/cli', true, '15.1.6'),
            addPackageJsonDependency(options.name, '@angular/compiler-cli', true, '15.1.5'),
            addPackageJsonDependency(options.name, '@types/jasmine', true, '4.3.1'),
            addPackageJsonDependency(options.name, '@typescript-eslint/eslint-plugin', true, '5.59.0'),
            addPackageJsonDependency(options.name, '@typescript-eslint/parser', true, '5.59.0'),
            addPackageJsonDependency(options.name, 'eslint', true, '8.38.0'),
            addPackageJsonDependency(options.name, 'eslint-config-standard', true, '17.0.0'),
            addPackageJsonDependency(options.name, 'eslint-plugin-import', true, '2.27.5'),
            addPackageJsonDependency(options.name, 'eslint-plugin-n', true, '15.7.0'),
            addPackageJsonDependency(options.name, 'eslint-plugin-promise', true, '6.1.1'),
            addPackageJsonDependency(options.name, 'jasmine-core', true, '4.6.0'),
            addPackageJsonDependency(options.name, 'karma', true, '6.4.1'),
            addPackageJsonDependency(options.name, 'karma-chrome-launcher', true, '3.1.1'),
            addPackageJsonDependency(options.name, 'karma-coverage', true, '2.2.0'),
            addPackageJsonDependency(options.name, 'karma-jasmine', true, '5.1.0'),
            addPackageJsonDependency(options.name, 'karma-jasmine-html-reporter', true, '2.0.0'),
            addPackageJsonDependency(options.name, 'ngx-build-plus', true, "15.0.0"),
            addPackageJsonDependency(options.name, 'typescript', true, "4.8.2"),
            addPackageJsonDependency(options.name, 'adm-zip', true, "0.5.10"),
            addPackageJsonDependency(options.name, 'axios', true, "1.3.4"),
            sortPackageJsonDependencies(options.name),
            
            installNodePackages(options.name)
        ]);
        return rule(tree, context) as Rule;
    };
}

function addPackageJsonDependency(projectName: string, packageName: string, isDevDependency: boolean = false, version?: string): Rule {
    return (tree: Tree, _: SchematicContext) => {
        const observer = new Observable<Tree>((observer) => {
            if (version != null) {
                observer.next(writePackageJsonDependency(tree, projectName, packageName, version, isDevDependency));
                console.info(`Package dependency added: ${packageName} ${version}${isDevDependency ? ' (Dev)' : ''}`);
                observer.complete();

                return observer;
            }

            fetch('https://registry.npmjs.org/' + packageName + '/latest')
                .then(res => res.json())
                .then(data => {
                    observer.next(writePackageJsonDependency(tree, projectName, packageName, data.version, isDevDependency));
                    console.info(`Package dependency added: ${packageName} ${data.version}${isDevDependency ? ' (Dev)' : ''}`);
                    observer.complete();
                })
                .catch(function (err: any) {
                    console.error(err);
                    observer.next(writePackageJsonDependency(tree, projectName, packageName, 'latest', isDevDependency));
                    console.info(`Failed to fetch package info for: ${packageName}${isDevDependency ? ' (Dev) ' : ''}- Using fallback package version "latest" (Please amend the version number of the mentioned package inside ${projectName}/package.json file).`);
                    observer.complete();
                });
        });

        return observer;
    };
}

function sortPackageJsonDependencies(projectName: string): Rule {
    return (tree: Tree, _: SchematicContext): Tree => {
        console.info('Sorting package.json dependencies...');
        const path = `/${projectName}/package.json`;
        const json = getPackageJson(tree, path);

        json.dependencies = sortPackageJsonObjectByKeys(json.dependencies);
        json.devDependencies = sortPackageJsonObjectByKeys(json.devDependencies);

        tree.overwrite(path, JSON.stringify(json, null, 2));

        return tree;
    };
}

function installNodePackages(projectName: string): Rule {
    return (tree: Tree, context: SchematicContext): Tree => {
        console.info('Installing node packages...');
        context.addTask(
            new NodePackageInstallTask({
                workingDirectory: projectName,
                packageManager: 'npm',
            })
        );

        return tree;
    };
}

// --- Utility

function getPackageJson(tree: Tree, path: string): PackageJson {
    const file = tree.read(path);

    return JSON.parse(file!.toString()) as PackageJson;
}

function writePackageJsonDependency(tree: Tree, projectName: string, packageName: string, version: string, isDevDependency: boolean): Tree {
    const path = `/${projectName}/package.json`;
    const json = getPackageJson(tree, path);

    if (isDevDependency) {
        json.devDependencies = {
            ...json.devDependencies,
            [packageName]: version
        };
    }
    else {
        json.dependencies = {
            ...json.dependencies,
            [packageName]: version
        };
    }

    tree.overwrite(path, JSON.stringify(json, null, 2));

    return tree;
}

function sortPackageJsonObjectByKeys(obj: Record<string, string>): Record<string, string> {
    return Object.keys(obj)
        .sort()
        .reduce((result, key) => {
            result[key] = obj[key];
            return result;
        }, {} as Record<string, string>);
}