package systemd

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/warkanum/unitdore/config"
)

func TestServiceName(t *testing.T) {
	u := config.Unit{Name: "nginx"}

	tests := []struct {
		prefix, suffix, want string
	}{
		{"", "", "unitdore-nginx.service"},
		{"prod-", "", "unitdore-prod-nginx.service"},
		{"", "-web", "unitdore-nginx-web.service"},
		{"prod-", "-web", "unitdore-prod-nginx-web.service"},
	}

	for _, tt := range tests {
		got := ServiceName(u, tt.prefix, tt.suffix)
		if got != tt.want {
			t.Errorf("ServiceName(%q, %q) = %q, want %q", tt.prefix, tt.suffix, got, tt.want)
		}
	}
}

func TestGenerate_SystemUnit(t *testing.T) {
	u := config.Unit{
		Name:    "nginx",
		Runtime: "podman",
		Order:   1,
		Enabled: true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	checks := []string{
		"[Unit]",
		"[Service]",
		"[Install]",
		"unitdore-nginx.service",
		"Description=Unitdore: nginx (podman)",
		"After=network.target",
		"WantedBy=multi-user.target",
		"ExecStart=/usr/bin/podman start -a nginx",
		"ExecStop=-/usr/bin/podman stop nginx",
		"Generated by unitdore",
	}

	for _, check := range checks {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() missing %q in output:\n%s", check, content)
		}
	}

	if strings.Contains(content, "User=") {
		t.Errorf("Generate() system unit should not contain User= directive:\n%s", content)
	}
	if strings.Contains(content, "Requires=") {
		t.Errorf("Generate() podman system unit should not contain Requires= (podman is daemonless):\n%s", content)
	}
	if strings.Contains(content, "Restart=") {
		t.Errorf("Generate() restart should be disabled by default:\n%s", content)
	}
}

func TestGenerate_UserUnit(t *testing.T) {
	u := config.Unit{
		Name:    "myapp",
		Runtime: "docker",
		User:    "hein",
		Order:   2,
		Enabled: true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	checks := []string{
		"After=default.target",
		"WantedBy=default.target",
		"ExecStart=/usr/bin/docker start -a myapp",
		"ExecStop=-/usr/bin/docker stop myapp",
	}

	for _, check := range checks {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() user unit missing %q in output:\n%s", check, content)
		}
	}

	if strings.Contains(content, "WantedBy=multi-user.target") {
		t.Error("Generate() user unit should not contain multi-user.target")
	}
}

func TestGenerate_WithRestart(t *testing.T) {
	t.Run("restart with retries", func(t *testing.T) {
		u := config.Unit{
			Name:           "nginx",
			Runtime:        "podman",
			Enabled:        true,
			Restart:        true,
			RestartSec:     5,
			RestartRetries: 3,
		}
		content, err := Generate(u, "", "")
		if err != nil {
			t.Fatalf("Generate() error: %v", err)
		}
		for _, want := range []string{"Restart=on-failure", "RestartSec=5", "StartLimitBurst=3"} {
			if !strings.Contains(content, want) {
				t.Errorf("Generate() missing %q in output:\n%s", want, content)
			}
		}
	})

	t.Run("restart without retries", func(t *testing.T) {
		u := config.Unit{
			Name:       "nginx",
			Runtime:    "podman",
			Enabled:    true,
			Restart:    true,
			RestartSec: 10,
		}
		content, err := Generate(u, "", "")
		if err != nil {
			t.Fatalf("Generate() error: %v", err)
		}
		if !strings.Contains(content, "Restart=on-failure") {
			t.Errorf("Generate() missing Restart=on-failure:\n%s", content)
		}
		if !strings.Contains(content, "RestartSec=10") {
			t.Errorf("Generate() missing RestartSec=10:\n%s", content)
		}
		if strings.Contains(content, "StartLimitBurst") {
			t.Errorf("Generate() should not contain StartLimitBurst when retries=0:\n%s", content)
		}
	})
}

func TestGenerate_CustomCommand(t *testing.T) {
	u := config.Unit{
		Name:    "custom",
		Runtime: "podman",
		Command: "/usr/local/bin/mystart.sh",
		Enabled: true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	if !strings.Contains(content, "ExecStart=/usr/local/bin/mystart.sh") {
		t.Errorf("Generate() should use custom command, got:\n%s", content)
	}
}

func TestGenerate_DockerRuntime(t *testing.T) {
	u := config.Unit{
		Name:    "redis",
		Runtime: "docker",
		Enabled: true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	checks := []string{
		"ExecStart=/usr/bin/docker start -a redis",
		"ExecStop=-/usr/bin/docker stop redis",
		"After=network.target docker.service",
		"Requires=docker.service",
	}
	for _, check := range checks {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() docker runtime missing %q in output:\n%s", check, content)
		}
	}
}

func TestGenerate_UnknownRuntime(t *testing.T) {
	u := config.Unit{
		Name:    "weird",
		Runtime: "containerd",
		Enabled: true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() should not error on unknown runtime: %v", err)
	}

	if !strings.Contains(content, "/usr/bin/containerd start weird") {
		t.Errorf("Generate() should fall back to /usr/bin/<runtime> for unknown runtimes:\n%s", content)
	}
}

func TestGenerate_WithPrefixSuffix(t *testing.T) {
	u := config.Unit{
		Name:    "nginx",
		Runtime: "podman",
		Enabled: true,
	}

	content, err := Generate(u, "prod-", "-web")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	if !strings.Contains(content, "unitdore-prod-nginx-web.service") {
		t.Errorf("Generate() prefix+suffix not reflected in service name:\n%s", content)
	}
}

// newComposeStack creates a stack unit whose compose binary, working dir and
// compose file exist on disk (compose mode).
func newComposeStack(t *testing.T) config.Unit {
	t.Helper()
	dir := t.TempDir()
	bin := filepath.Join(dir, "podman-compose")
	if err := os.WriteFile(bin, []byte("#!/bin/sh\n"), 0755); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(dir, "compose.yaml"), []byte("services: {}\n"), 0644); err != nil {
		t.Fatal(err)
	}
	return config.Unit{
		Name:         "shop",
		Runtime:      "podman",
		Kind:         config.KindStack,
		Project:      "shop",
		WorkingDir:   dir,
		ComposeFiles: []string{"compose.yaml"},
		ComposeBin:   bin,
		Enabled:      true,
	}
}

func TestGenerate_StackCompose(t *testing.T) {
	u := newComposeStack(t)
	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}
	base := u.ComposeBin + " -p shop -f compose.yaml"
	for _, want := range []string{
		"Description=Unitdore: shop (podman-compose stack)",
		"Type=simple",
		"WorkingDirectory=" + u.WorkingDir,
		"ExecStart=" + base + " up",
		"ExecStop=-" + base + " stop",
		"WantedBy=multi-user.target",
	} {
		if !strings.Contains(content, want) {
			t.Errorf("Generate() missing %q in output:\n%s", want, content)
		}
	}
	if strings.Contains(content, "RemainAfterExit") || strings.Contains(content, "Requires=") {
		t.Errorf("compose stack unit has unexpected directives:\n%s", content)
	}
}

func TestGenerate_StackPodFallback(t *testing.T) {
	u := newComposeStack(t)
	u.ComposeBin = ""
	u.User = "hein"
	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}
	for _, want := range []string{
		"Description=Unitdore: shop (podman pod)",
		"Type=oneshot",
		"RemainAfterExit=yes",
		"ExecStart=/usr/bin/podman pod start pod_shop",
		"ExecStop=-/usr/bin/podman pod stop pod_shop",
		"WantedBy=default.target",
	} {
		if !strings.Contains(content, want) {
			t.Errorf("Generate() missing %q in output:\n%s", want, content)
		}
	}
	if strings.Contains(content, "WorkingDirectory=") {
		t.Errorf("pod fallback should not set WorkingDirectory:\n%s", content)
	}
}

func TestGenerate_StackCustomCommand(t *testing.T) {
	u := newComposeStack(t)
	u.Command = "/usr/local/bin/stack.sh"
	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}
	if !strings.Contains(content, "ExecStart=/usr/local/bin/stack.sh") {
		t.Errorf("custom command should override stack commands:\n%s", content)
	}
}

func TestGenerate_Script(t *testing.T) {
	u := config.Unit{
		Name:       "backup",
		Runtime:    config.RuntimeScript,
		Script:     "/opt/scripts/backup.sh",
		StopScript: "/opt/scripts/backup-stop.sh",
		WorkingDir: "/opt/scripts",
		Enabled:    true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	checks := []string{
		"Description=Unitdore: backup (bash script)",
		"Type=simple",
		"WorkingDirectory=/opt/scripts",
		"ExecStart=/bin/bash /opt/scripts/backup.sh",
		"ExecStop=-/bin/bash /opt/scripts/backup-stop.sh",
	}
	for _, check := range checks {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() script missing %q in output:\n%s", check, content)
		}
	}
	if strings.Contains(content, "Requires=") {
		t.Errorf("Generate() script unit should not contain Requires=:\n%s", content)
	}
}

func TestGenerate_ScriptOneshotUserQuoted(t *testing.T) {
	u := config.Unit{
		Name:        "setup",
		Runtime:     config.RuntimeScript,
		User:        "alice",
		Script:      "/home/alice/my scripts/setup.sh",
		ServiceType: "oneshot",
		Enabled:     true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}

	checks := []string{
		"Type=oneshot",
		"RemainAfterExit=yes",
		`ExecStart=/bin/bash "/home/alice/my scripts/setup.sh"`,
		"WantedBy=default.target",
	}
	for _, check := range checks {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() missing %q in output:\n%s", check, content)
		}
	}
	if strings.Contains(content, "ExecStop=-") {
		t.Errorf("Generate() should have no stop command without stop_script:\n%s", content)
	}
}

func TestGenerate_ScriptMissingPath(t *testing.T) {
	u := config.Unit{Name: "bad", Runtime: config.RuntimeScript, Enabled: true}
	if _, err := Generate(u, "", ""); err == nil {
		t.Error("Generate() should error when script path is empty")
	}
}

func TestGenerate_ScriptCustomShell(t *testing.T) {
	u := config.Unit{
		Name:    "fishy",
		Runtime: config.RuntimeScript,
		Shell:   "/usr/bin/zsh",
		Script:  "/opt/run.zsh",
		Enabled: true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}
	for _, check := range []string{"Description=Unitdore: fishy (zsh script)", "ExecStart=/usr/bin/zsh /opt/run.zsh"} {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() missing %q in output:\n%s", check, content)
		}
	}
}

func TestGenerate_Executable(t *testing.T) {
	u := config.Unit{
		Name:           "agent",
		Runtime:        config.RuntimeExec,
		Executable:     "/opt/agent/bin/agent",
		Args:           []string{"--config", "/etc/my agent.toml"},
		StopExecutable: "/opt/agent/bin/agent-stop",
		WorkingDir:     "/opt/agent",
		ServiceType:    "oneshot",
		Enabled:        true,
	}

	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatalf("Generate() error: %v", err)
	}
	checks := []string{
		"Description=Unitdore: agent (executable)",
		"Type=oneshot",
		"WorkingDirectory=/opt/agent",
		`ExecStart=/opt/agent/bin/agent --config "/etc/my agent.toml"`,
		"ExecStop=-/opt/agent/bin/agent-stop",
	}
	for _, check := range checks {
		if !strings.Contains(content, check) {
			t.Errorf("Generate() missing %q in output:\n%s", check, content)
		}
	}
}

func TestGenerate_ExecutableMissingPath(t *testing.T) {
	u := config.Unit{Name: "bad", Runtime: config.RuntimeExec, Enabled: true}
	if _, err := Generate(u, "", ""); err == nil {
		t.Error("Generate() should error when executable is empty")
	}
}

func TestGenerate_OrderAndDelay(t *testing.T) {
	u := config.Unit{Name: "web", Runtime: "podman", Enabled: true, After: []string{"db", "cache"}, StartDelay: 1500 * time.Millisecond}
	content, err := Generate(u, "p-", "")
	if err != nil {
		t.Fatal(err)
	}
	for _, want := range []string{
		"After=network.target unitdore-p-db.service unitdore-p-cache.service\n",
		"ExecStartPre=/usr/bin/env sleep 2\n",
		"TimeoutStartSec=92\n",
	} {
		if !strings.Contains(content, want) {
			t.Errorf("missing %q in:\n%s", want, content)
		}
	}
}

func TestGenerate_UserUnitOrder(t *testing.T) {
	u := config.Unit{Name: "web", Runtime: "podman", User: "hein", Enabled: true, After: []string{"db"}}
	content, err := Generate(u, "", "")
	if err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(content, "After=default.target unitdore-db.service\n") {
		t.Errorf("user unit missing ordering:\n%s", content)
	}
	if strings.Contains(content, "ExecStartPre") {
		t.Errorf("no delay expected:\n%s", content)
	}
}

func TestGenerate_NoOrderNoExtras(t *testing.T) {
	content, err := Generate(config.Unit{Name: "a", Runtime: "podman", Enabled: true}, "", "")
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(content, "ExecStartPre") || strings.Contains(content, "TimeoutStartSec") || !strings.Contains(content, "After=network.target\n") {
		t.Errorf("unexpected ordering output:\n%s", content)
	}
}