package dehub

import (
	"dehub/sigcred"
	"reflect"
	"strings"
	"testing"

	"github.com/davecgh/go-spew/spew"
	"gopkg.in/src-d/go-git.v4"
	"gopkg.in/src-d/go-git.v4/plumbing"
	yaml "gopkg.in/yaml.v2"
)

func TestChangeCommitVerify(t *testing.T) {
	type step struct {
		msg     string
		msgHead string // defaults to msg
		tree    map[string]string
	}
	testCases := []struct {
		descr string
		steps []step
	}{
		{
			descr: "single commit",
			steps: []step{
				{
					msg:  "first commit",
					tree: map[string]string{"a": "0", "b": "1"},
				},
			},
		},
		{
			descr: "multiple commits",
			steps: []step{
				{
					msg:  "first commit",
					tree: map[string]string{"a": "0", "b": "1"},
				},
				{
					msg:  "second commit, changing a",
					tree: map[string]string{"a": "1"},
				},
				{
					msg: "third commit, empty",
				},
				{
					msg:  "fourth commit, adding c, removing b",
					tree: map[string]string{"b": "", "c": "2"},
				},
			},
		},
		{
			descr: "big body commits",
			steps: []step{
				{
					msg: "first commit, single line but with newline\n",
				},
				{
					msg:     "second commit, single line but with two newlines\n\n",
					msgHead: "second commit, single line but with two newlines\n\n",
				},
				{
					msg:     "third commit, multi-line with one newline\nanother line!",
					msgHead: "third commit, multi-line with one newline\n\n",
				},
				{
					msg:     "fourth commit, multi-line with two newlines\n\nanother line!",
					msgHead: "fourth commit, multi-line with two newlines\n\n",
				},
			},
		},
	}

	for _, test := range testCases {
		t.Run(test.descr, func(t *testing.T) {
			h := newHarness(t)
			for _, step := range test.steps {
				h.stage(step.tree)
				account := h.cfg.Accounts[0]

				changeCommit, hash := h.changeCommit(step.msg, account.ID, h.sig)
				if err := h.repo.VerifyChangeCommit(MainRefName, hash); err != nil {
					t.Fatalf("could not verify hash %v: %v", hash, err)
				}

				commit, err := h.repo.GitRepo.CommitObject(hash)
				if err != nil {
					t.Fatalf("failed to retrieve commit %v: %v", hash, err)
				} else if step.msgHead == "" {
					step.msgHead = strings.TrimSpace(step.msg) + "\n\n"
				}

				if !strings.HasPrefix(commit.Message, step.msgHead) {
					t.Fatalf("commit message %q does not start with expected head %q", commit.Message, step.msgHead)
				}

				var actualChangeCommit ChangeCommit
				if err := actualChangeCommit.UnmarshalText([]byte(commit.Message)); err != nil {
					t.Fatalf("error unmarshaling commit body: %v", err)
				} else if !reflect.DeepEqual(actualChangeCommit, changeCommit) {
					t.Fatalf("returned change commit:\n%s\ndoes not match actual one:\n%s",
						spew.Sdump(changeCommit), spew.Sdump(actualChangeCommit))
				}
			}
		})
	}
}

func TestConfigChange(t *testing.T) {
	h := newHarness(t)

	var hashes []plumbing.Hash

	// commit the initial staged changes, which merely include the config and
	// public key
	_, hash := h.changeCommit("commit configuration", h.cfg.Accounts[0].ID, h.sig)
	hashes = append(hashes, hash)

	// create a new account and add it to the configuration. That commit should
	// not be verifiable, though
	newSig, newPubKeyBody := sigcred.SignifierPGPTmp(h.rand)
	h.cfg.Accounts = append(h.cfg.Accounts, Account{
		ID: "toot",
		Signifiers: []sigcred.Signifier{{PGPPublicKey: &sigcred.SignifierPGP{
			Body: string(newPubKeyBody),
		}}},
	})
	h.cfg.AccessControls[0].ChangeAccessControls[0].Condition.Signature.AccountIDs = []string{"root", "toot"}
	h.cfg.AccessControls[0].ChangeAccessControls[0].Condition.Signature.Count = "1"

	cfgBody, err := yaml.Marshal(h.cfg)
	if err != nil {
		t.Fatal(err)
	}
	h.stage(map[string]string{ConfigPath: string(cfgBody)})
	_, badHash := h.changeCommit("add toot user", h.cfg.Accounts[1].ID, newSig)

	if err := h.repo.VerifyChangeCommit(MainRefName, badHash); err == nil {
		t.Fatal("toot user shouldn't be able to add itself to config")
	}
	h.reset(hash, git.HardReset)

	// now add with the root user, this should work.
	h.stage(map[string]string{ConfigPath: string(cfgBody)})
	_, hash = h.changeCommit("add toot user", h.cfg.Accounts[0].ID, h.sig)
	hashes = append(hashes, hash)

	// _now_ the toot user should be able to do things.
	h.stage(map[string]string{"foo/bar": "what a cool file"})
	_, hash = h.changeCommit("add a cool file", h.cfg.Accounts[1].ID, newSig)
	hashes = append(hashes, hash)

	for i, hash := range hashes {
		if err := h.repo.VerifyChangeCommit(MainRefName, hash); err != nil {
			t.Fatalf("commit %d (%v) should have been verified but wasn't: %v", i, hash, err)
		}
	}
}