package main

// Tests of kit.go, the same in each workstation module.

import (
	"strings"
	"testing"
	"time"
)

// fake records the commands asked and answers each from a function of the command line.
type fake struct {
	asked  []Cmd
	answer func(line string, c Cmd) Result
}

func (f *fake) runner() Runner {
	return func(c Cmd) Result {
		f.asked = append(f.asked, c)
		name, args := argv(c)
		line := strings.TrimSpace(name + " " + strings.Join(args, " "))
		if f.answer == nil {
			return Result{}
		}
		return f.answer(line, c)
	}
}

func (f *fake) lines() []string {
	out := []string{}
	for _, c := range f.asked {
		name, args := argv(c)
		out = append(out, strings.TrimSpace(name+" "+strings.Join(args, " ")))
	}
	return out
}

// using installs a fake runner and a non-root uid for one test.
func using(t *testing.T, answer func(line string, c Cmd) Result) *fake {
	t.Helper()
	f := &fake{answer: answer}
	wasRun, wasUID := run, euid
	run, euid = f.runner(), func() int { return 1000 }
	t.Cleanup(func() { run, euid = wasRun, wasUID })
	return f
}

func ok(stdout string) Result { return Result{Stdout: stdout} }

func TestKitAnActThatNeedsRootGoesThroughSudoWithoutAPromptUnlessAlreadyRoot(t *testing.T) {
	was := euid
	defer func() { euid = was }()
	euid = func() int { return 1000 }
	if name, args := argv(Cmd{Name: "x", Args: []string{"a"}, Root: true}); name != "sudo" || strings.Join(args, " ") != "-n x a" {
		t.Fatalf("not root: %s %v", name, args)
	}
	if name, _ := argv(Cmd{Name: "x"}); name != "x" {
		t.Fatalf("a read is run as the account: %s", name)
	}
	euid = func() int { return 0 }
	if name, _ := argv(Cmd{Name: "x", Root: true}); name != "x" {
		t.Fatalf("as root no sudo: %s", name)
	}
}

func TestKitAFailureIsNamedByHowItFailed(t *testing.T) {
	was := euid
	defer func() { euid = was }()
	euid = func() int { return 1000 }
	cases := []struct {
		c    Cmd
		r    Result
		want string
	}{
		{Cmd{Name: "nothere"}, Result{Status: 127, Error: "not-found"}, "not installed"},
		{Cmd{Name: "x", Root: true}, Result{Status: 127, Error: "not-found"}, "sudo is not installed"},
		{Cmd{Name: "x", Root: true}, Result{Status: 1, Stderr: "sudo: a password is required\n"}, "sudo -n refused"},
		{Cmd{Name: "x", Root: true}, Result{Status: 1, Stderr: "sudo: x: command not found\n"}, "x is not installed"},
		{Cmd{Name: "x"}, Result{Status: 124, Error: "timeout"}, "within 20s"},
		{Cmd{Name: "x", Args: []string{"y"}}, Result{Status: 3, Stderr: "boom\n"}, "x y exited 3: boom"},
		{Cmd{Name: "x"}, Result{Status: 3}, "said nothing"},
	}
	for _, k := range cases {
		err := failure(k.c, k.r)
		if err == nil || !strings.Contains(err.Error(), k.want) {
			t.Errorf("%+v: %v, want %q", k.r, err, k.want)
		}
	}
}

func TestKitOutputIsBoundedAndSaysSo(t *testing.T) {
	var w bounded
	big := strings.Repeat("a", MostOutput+10)
	n, _ := w.Write([]byte(big))
	if n != len(big) || w.b.Len() != MostOutput || !w.cut {
		t.Fatalf("kept %d of %d, cut %v", w.b.Len(), len(big), w.cut)
	}
}

func TestKitTheRealRunnerRunsEndsAndReportsAMissingProgram(t *testing.T) {
	r := execRun(Cmd{Name: "sh", Args: []string{"-c", "echo out; echo err >&2; exit 3"}})
	if r.Status != 3 || strings.TrimSpace(r.Stdout) != "out" || strings.TrimSpace(r.Stderr) != "err" {
		t.Fatalf("%+v", r)
	}
	r = execRun(Cmd{Name: "sh", Args: []string{"-c", "sleep 5 & sleep 5"}, Timeout: 200 * time.Millisecond})
	if r.Error != "timeout" {
		t.Fatalf("a slow command: %+v", r)
	}
	r = execRun(Cmd{Name: "no-such-program-anywhere"})
	if r.Error != "not-found" {
		t.Fatalf("a missing program: %+v", r)
	}
	r = execRun(Cmd{Name: "cat", Stdin: "given"})
	if r.Stdout != "given" {
		t.Fatalf("stdin: %+v", r)
	}
	start := time.Now()
	r = execRun(Cmd{Name: "sh", Args: []string{"-c", "echo kept; (sleep 3 &) ; exit 0"}, Detached: true})
	if r.Status != 0 || strings.TrimSpace(r.Stdout) != "kept" || time.Since(start) > 2*time.Second {
		t.Fatalf("a detached command returns when it exits, not when its child does: %+v after %s", r, time.Since(start))
	}
}

func TestKitArgumentsAreReadStrictly(t *testing.T) {
	args := map[string]any{"s": "x", "n": float64(5), "f": 1.5, "b": true, "l": []any{"a", "b"}}
	if _, err := text(args, "missing"); err == nil {
		t.Error("a missing required string")
	}
	if n, _ := optWhole(args, "n", 1, 1, 3); n != 3 {
		t.Errorf("held to most: %d", n)
	}
	if _, err := optWhole(args, "n", 1, 6, 9); err == nil {
		t.Error("below least")
	}
	if _, err := optWhole(args, "f", 1, 0, 9); err == nil {
		t.Error("a fraction")
	}
	if l, _ := optList(args, "l"); len(l) != 2 {
		t.Errorf("list: %v", l)
	}
	if b, _ := optFlag(args, "b", false); !b {
		t.Error("flag")
	}
	if err := plainName("name", "--all"); err == nil {
		t.Error("an option as a name")
	}
}