package main

import (
	"flag"
	"fmt"
	"os"

	"github.com/Mond1c/judge/dsl"
	"github.com/Mond1c/judge/reporter"
	"github.com/Mond1c/judge/runner"
)

const usage = `judge — CI/CD testing system for student solutions

Usage:
  judge <tests.jdg> <solution-dir> [flags]
  judge aggregate <reports-dir>

Flags:
  --json             output as JSON instead of text
  --wrapper <cmd>    exec wrapper (e.g. "valgrind --error-exitcode=99")
  --binary <name>    name of executable produced by build (overrides .jdg)
  --help             show help

Example:
  judge lab1.jdg ./student-solution
  judge lab1.jdg ./student-solution --json
  judge aggregate reports/
`

func main() {
	if len(os.Args) >= 2 && os.Args[1] == "aggregate" {
		runAggregate()
		return
	}

	fs := flag.NewFlagSet("judge", flag.ContinueOnError)
	fs.SetOutput(os.Stderr)
	fs.Usage = func() { fmt.Fprint(os.Stderr, usage) }

	jsonOutput := fs.Bool("json", false, "output as JSON")
	wrapper := fs.String("wrapper", "", "exec wrapper command")
	binary := fs.String("binary", "", "binary name override")

	if err := fs.Parse(os.Args[1:]); err != nil {
		os.Exit(2)
	}

	if fs.NArg() < 2 {
		fmt.Fprintf(os.Stderr, "error: need <tests.jdg> and <solution-dir>\n\n%s", usage)
		os.Exit(1)
	}

	testFile := fs.Arg(0)
	solutionDir := fs.Arg(1)

	src, err := os.ReadFile(testFile)
	if err != nil {
		fatalf("cannot read %q: %v", testFile, err)
	}

	f, warns, err := dsl.Parse(string(src))
	if err != nil {
		fatalf("parse error in %q:\n  %v", testFile, err)
	}
	for _, w := range warns {
		fmt.Fprintf(os.Stderr, "warning: %s\n", w)
	}

	if _, err := os.Stat(solutionDir); err != nil {
		fatalf("solution dir %q not found: %v", solutionDir, err)
	}

	r := runner.New(f, runner.Config{
		WorkDir:    solutionDir,
		BinaryName: *binary,
		Wrapper:    *wrapper,
	})
	result := r.Run()

	if *jsonOutput {
		if err := reporter.JSON(os.Stdout, result); err != nil {
			fatalf("json output error: %v", err)
		}
	} else {
		reporter.Text(os.Stdout, result)
	}

	if result.TotalScore < 0.9999 {
		os.Exit(1)
	}
}

func runAggregate() {
	if len(os.Args) < 3 {
		fatalf("usage: judge aggregate <reports-dir>")
	}
	dir := os.Args[2]
	if err := reporter.Aggregate(os.Stdout, dir); err != nil {
		fatalf("%v", err)
	}
}

func fatalf(msg string, args ...any) {
	fmt.Fprintf(os.Stderr, "error: "+msg+"\n", args...)
	os.Exit(1)
}