const chalk = require("chalk");
import * as R from "ramda";
import { diffLines } from "diff";
import { sentence } from "change-case";

import delta from "./delta";
import {
  ReporterPlugin,
  RunnerResult,
  PerturbConfig,
  PerturbMetadata,
} from "../types";

const plugin: ReporterPlugin = {
  name: "diff",
  type: "reporter",
  onResult(r: RunnerResult) {
    console.log(generateReport(r));
  },
  onFinish(rs: RunnerResult[], cfg: PerturbConfig, m?: PerturbMetadata) {
    const [killed] = R.partition(r => r.error, rs);
    const total = rs.length;
    const killCount = killed.length;
    const killRate = Number((killCount / total).toFixed(4)) * 100;
    console.log(`Total: ${total}. Killed: ${killCount}. Rate: ${killRate}%`);
    delta(rs, cfg);
  },
};
export default plugin;

function generateReport(r: RunnerResult): string {
  const plus = "+    ";
  const minus = "-    ";
  const alive = "#ALIVE: ";
  const dead = "#DEAD: ";

  const id = identifier(r);

  // if (r.error) {
  //   return chalk.gray(id);
  // }

  const title = r.error
    ? chalk.gray(dead + id)
    : chalk.red.underline(alive + id);

  return [
    title,
    ...generateDiff(r).map((entry: any) => {
      const color = r.error ? "gray" : entry.added ? "green" : "red";
      const sign = entry.added ? plus : minus;
      return chalk[color](
        entry.value
          .trim()
          .split("\n")
          .map((l: string) => sign + l)
          .join("\n"),
      );
    }),
  ].join("\n");
}

function generateDiff(r: RunnerResult) {
  return diffLines(r.originalSourceCode, r.mutatedSourceCode).filter(
    (node: any) => node.added || node.removed,
  );
}

function identifier(r: RunnerResult) {
  const loc = r.loc.start.line + "," + r.loc.start.column;

  // hack :/
  const file = r.sourceFile.split(".perturb")[1];

  return sentence(r.mutatorName) + " " + file + "@" + loc;
}