package wand

import (
	"bytes"
	"fmt"
	"io"
	"strings"
	"testing"
)

type testCase struct {
	impl any
	stdin string
	conf string
	env string
	command string
}

func testExec(test testCase, err string, expect ...string) func(*testing.T) {
	return func(t *testing.T) {
		var exitCode int
		exit := func(code int) { exitCode = code }

		var stdinr io.Reader
		if test.stdin != "" {
			stdinr = bytes.NewBuffer([]byte(test.stdin))
		}

		stdout := bytes.NewBuffer(nil)
		stderr := bytes.NewBuffer(nil)
		cmd := wrap(test.impl)
		e := strings.Split(test.env, ";")
		a := strings.Split(test.command, " ")
		exec(stdinr, stdout, stderr, exit, cmd, Config{test: test.conf}, e, a)
		if exitCode != 0 && err == "" {
			t.Fatal("non-zero exit code:", stderr.String())
		}

		if err != "" && exitCode == 0 {
			t.Fatal("failed to fail")
		}

		if err != "" && !strings.Contains(stderr.String(), err) {
			t.Fatal("expected error not received:", stderr.String())
		}

		if exitCode != 0 {
			return
		}

		var expstr []string
		for _, e := range expect {
			expstr = append(expstr, fmt.Sprint(e))
		}

		output := stdout.String()
		if output[len(output) - 1] != '\n' {
			output = output + "\n"
		}

		if output != strings.Join(expstr, "\n")+"\n" {
			t.Fatal("unexpected output:", stdout.String())
		}
	}
}