package faas

import (
	"fmt"
	"io/ioutil"
	"os"
	"path/filepath"
	"testing"
)

// TestPathToDomain validatest the calculation used to derive a default domain
// for a Function from the current directory path (used as a default
// in the absence of an explicit setting).
// NOTE: although the implementation uses os.PathSeparator and is developed with
// non-unix platforms in mind, these tests are written using unix-style paths.
func TestPathToDomain(t *testing.T) {
	var noLimit = -1
	tests := []struct {
		Path   string // input path
		Limit  int    // upward recursion limit
		Domain string // Expected returned domain value
	}{
		// empty input should not find a domain.
		{"", noLimit, ""},

		// trailing slashes ignored
		{"/home/user/example.com/admin/", noLimit, "admin.example.com"},

		// root path should not find a domain.
		{"/", noLimit, ""},

		// valid path but without a domain should find no domain.
		{"/home/user", noLimit, ""},

		// valid domain as the current directory should be found.
		{"/home/user/example.com", noLimit, "example.com"},

		// valid domain as the current directory should be found even with recursion disabled.
		{"/home/user/example.com", 0, "example.com"},

		// Subdomain
		{"/src/example.com/www", noLimit, "www.example.com"},

		// Subdomain with recursion disabled should not find the domain.
		{"/src/example.com/www", 0, ""},

		// Sub-subdomain
		{"/src/example.com/www/test1", noLimit, "test1.www.example.com"},

		// Sub-subdomain with exact recursion limit to catch the domain
		{"/src/example.com/www/test1", 2, "test1.www.example.com"},

		// CWD a valid TLD+1 (not suggested, but supported)
		{"/src/my.example.com", noLimit, "my.example.com"},

		// Multi-level TLDs
		{"/src/example.co.uk", noLimit, "example.co.uk"},

		// Multi-level TLDs with sub
		{"/src/example.co.uk/www", noLimit, "www.example.co.uk"},

		// Expected behavior is `test1.my.example.com` but will yield `test1.my`
		// because .my is a TLD hence the reason why dots in directories to denote
		// multiple levels of subdomain are technically supported but not
		// recommended: unexpected behavior because the public suffices list is
		// shifty.
		{"/src/example.com/test1.my", noLimit, "test1.my"},

		// Ensure that cluster.local is explicitly allowed.
		{"/src/cluster.local/www", noLimit, "www.cluster.local"},
	}

	for _, test := range tests {
		domain := pathToDomain(test.Path, test.Limit)
		if domain != test.Domain {
			t.Fatalf("expected path '%v' (limit %v) to yield domain '%v', got '%v'", test.Path, test.Limit, test.Domain, domain)
		}
	}
}

// TestApplyConfig ensures that
// - a directory with no config has nothing applied without error.
// - a directory with an invalid config errors.
// - a directory with a valid config has it applied.
func TestApplyConfig(t *testing.T) {
	// Create a temporary directory
	root := "./testdata/example.com/cfgtest"
	cfgFile := filepath.Join(root, ConfigFileName)
	err := os.MkdirAll(root, 0700)
	if err != nil {
		fmt.Println("Error on TestApplyConfig: ", err)
		return
	}
	defer os.RemoveAll(root)

	c := Function{name: "staticDefault"}

	// Assert config optional.
	// Ensure that applying a directory with no config does not error.
	if err := applyConfig(&c, root); err != nil {
		t.Fatalf("unexpected error applying a nonexistent config: %v", err)
	}

	// Assert an extant, but empty config file causes no errors,
	// and leaves data intact on the client instance.
	if err := ioutil.WriteFile(cfgFile, []byte(""), 0644); err != nil {
		t.Fatal(err)
	}
	if err := applyConfig(&c, root); err != nil {
		t.Fatalf("unexpected error applying an empty config: %v", err)
	}

	// Assert an unparseable config file errors
	if err := ioutil.WriteFile(cfgFile, []byte("=invalid="), 0644); err != nil {
		t.Fatal(err)
	}
	if err := applyConfig(&c, root); err == nil {
		t.Fatal("Did not receive expected error from invalid config.")
	}

	// Assert a valid config with no value zeroes out the default
	if err := ioutil.WriteFile(cfgFile, []byte("name:"), 0644); err != nil {
		t.Fatal(err)
	}
	if err := applyConfig(&c, root); err != nil {
		t.Fatal(err)
	}
	if c.name != "" {
		t.Fatalf("Expected name to be zeroed by config, but got '%v'", c.name)
	}

	// Assert a valid config with a value for name is applied.
	if err := ioutil.WriteFile(cfgFile, []byte("name: www.example.com"), 0644); err != nil {
		t.Fatal(err)
	}
	if err := applyConfig(&c, root); err != nil {
		t.Fatal(err)
	}
	if c.name != "www.example.com" {
		t.Fatalf("Expected name 'www.example.com', got '%v'", c.name)
	}
}