"use strict";

import { parallel } from "async";
import { readFile } from "fs";
import * as glob from "glob";
import { join } from "path";

import { Task } from "../../types";

const autoGeneratedMarker
    = "//------------------------------------------------------------------------------\n"
    + "// <auto-generated>";

const flagDoneName = "dotnetcheckerDone";

export default ((params, processor) => () => {
    if (processor.context.containsFlag(flagDoneName)) {
        return processor.done();
    }

    processor.context.addFlag(flagDoneName);

    return glob("**/*.cs", { cwd: processor.context.exported }, (globErr, files) => {
        if (globErr) {
            processor.onError(globErr);

            return processor.done();
        }

        processor.onInfo(`Found ${files.length} .cs files`);

        if (!files || !files.length) {
            processor.onWarn("No .cs files found");

            return processor.done();
        }

        const processFile = (data, file) => {
            if (data.includes("\r\n")) {
                return processor.onError(`Windows-style EOL (0D0A) found in file ${file}`);
            }

            if (!params.ignoreCodeStyle) {
                if (data.substr(1, autoGeneratedMarker.length) === autoGeneratedMarker || data.startsWith(autoGeneratedMarker)) {
                    return processor.onInfo(`Skipping auto-generated file ${file}`);
                }

                if (data.includes("\t") && data.includes("    ")) {
                    processor.onError(`Both tabs and spaces found in file ${file}`);
                }

                if (data.includes("\t")) {
                    processor.onError(`Tabs found in file ${file}`);
                }
            }

            return processor.onInfo(`Checked file ${file}`);
        };

        return parallel(files.map((file) => (callback) => readFile(
            join(processor.context.exported, file),
            { encoding: "utf8" },
            (readErr, data) => {
                if (readErr) {
                    processor.onError(`Unable to check file ${file}: ${readErr}`);

                    return callback(readErr);
                }

                processFile(data, file);

                return callback();
            },
        )), processor.done);
    });
}) as Task;