package main

/*
	This program runs all unit tests in the repository.
*/

import (
	"bufio"
	"bytes"
	"fmt"
	"os"
	"os/exec"
	"path"
	"path/filepath"
	"runtime"
	"strings"
	"sync"

	"go.skia.org/infra/go/common"
	"go.skia.org/infra/go/fileutil"
	"go.skia.org/infra/go/sklog"
	"go.skia.org/infra/go/testutils"
	"go.skia.org/infra/go/timer"
	"go.skia.org/infra/go/util"
)

const (
	// This gets filled out and printed when a test fails.
	TEST_FAILURE = `
============================= TEST FAILURE =============================
Test: %s

Command: %s

Error:
%s

Full output:
------------------------------------------------------------------------
%s
------------------------------------------------------------------------
`
)

var (
	// Error message shown when a required executable is not installed.
	ERR_NEED_INSTALL = "%s failed to run! Is it installed? Error: %v"

	// Directories with these names are skipped when searching for tests.
	NO_CRAWL_DIR_NAMES = []string{
		".git",
		".recipe_deps",
		"assets",
		"bower_components",
		"third_party",
		"node_modules",
	}

	// Directories with these paths, relative to the checkout root, are
	// skipped when searching for tests.
	NO_CRAWL_REL_PATHS = []string{
		"common",
	}

	POLYMER_PATHS = []string{
		"res/imp",
		"alertserver/res/imp",
		"autoroll/res/imp",
		"fuzzer/res/imp",
		"status/res/imp",
	}
)

// cmdTest returns a test which runs a command and fails if the command fails.
func cmdTest(cmd []string, cwd, name, testType string) *test {
	return &test{
		Name: name,
		Cmd:  strings.Join(cmd, " "),
		run: func() (error, string) {
			command := exec.Command(cmd[0], cmd[1:]...)
			if cwd != "" {
				command.Dir = cwd
			}
			output, err := command.CombinedOutput()
			if err != nil {
				if _, err2 := exec.LookPath(cmd[0]); err2 != nil {
					return fmt.Errorf(ERR_NEED_INSTALL, cmd[0], err), string(output)
				}
			}
			return err, string(output)
		},
		Type: testType,
	}
}

func polylintTest(cwd, fileName string) *test {
	cmd := []string{"polylint", "--no-recursion", "--root", cwd, "--input", fileName}
	return &test{
		Name: fmt.Sprintf("polylint in %s", filepath.Join(cwd, fileName)),
		Cmd:  strings.Join(cmd, " "),
		run: func() (error, string) {
			command := exec.Command(cmd[0], cmd[1:]...)
			outputBytes, err := command.Output()
			if err != nil {
				if _, err2 := exec.LookPath(cmd[0]); err2 != nil {
					return fmt.Errorf(ERR_NEED_INSTALL, cmd[0], err), string(outputBytes)
				}
				return err, string(outputBytes)
			}

			unresolvedProblems := ""
			count := 0

			for s := bufio.NewScanner(bytes.NewBuffer(outputBytes)); s.Scan(); {
				badFileLine := s.Text()
				if !s.Scan() {
					return fmt.Errorf("Unexpected end of polylint output after %q:\n%s", badFileLine, string(outputBytes)), string(outputBytes)
				}
				problemLine := s.Text()
				if !strings.Contains(unresolvedProblems, badFileLine) {
					unresolvedProblems = fmt.Sprintf("%s\n%s\n%s", unresolvedProblems, badFileLine, problemLine)
					count++
				}
			}

			if unresolvedProblems == "" {
				return nil, ""
			}
			return fmt.Errorf("%d unresolved polylint problems:\n%s\n", count, unresolvedProblems), ""
		},
		Type: testutils.LARGE_TEST,
	}
}

// buildPolymerFolder runs the Makefile in the given folder.  This sets up the symbolic links so dependencies can be located for polylint.
func buildPolymerFolder(cwd string) error {
	cmd := cmdTest([]string{"make"}, cwd, fmt.Sprintf("Polymer build in %s", cwd), testutils.LARGE_TEST)
	return cmd.Run()
}

// polylintTestsForDir builds the folder once and then returns a list of tests for each Polymer file in the directory.  If the build fails, a dummy test is returned that prints an error message.
func polylintTestsForDir(cwd string, fileNames ...string) []*test {
	if err := buildPolymerFolder(cwd); err != nil {
		return []*test{
			&test{
				Name: filepath.Join(cwd, "make"),
				Cmd:  filepath.Join(cwd, "make"),
				run: func() (error, string) {
					return fmt.Errorf("Could not build Polymer files in %s: %s", cwd, err), ""
				},
				Type: testutils.LARGE_TEST,
			},
		}
	}
	tests := make([]*test, 0, len(fileNames))
	for _, name := range fileNames {
		tests = append(tests, polylintTest(cwd, name))
	}
	return tests
}

// findPolymerFiles returns all files that probably contain polymer content (i.e. end with sk.html) in a given directory.
func findPolymerFiles(dirPath string) []string {
	dir := fileutil.MustOpen(dirPath)
	files := make([]string, 0)
	for _, info := range fileutil.MustReaddir(dir) {
		if n := info.Name(); strings.HasSuffix(info.Name(), "sk.html") {
			files = append(files, n)
		}
	}
	return files
}

//polylintTests creates a list of *test from all directories in POLYMER_PATHS
func polylintTests() []*test {
	tests := make([]*test, 0)
	for _, path := range POLYMER_PATHS {
		tests = append(tests, polylintTestsForDir(path, findPolymerFiles(path)...)...)
	}
	return tests
}

// goTest returns a test which runs `go test` in the given cwd.
func goTest(cwd string, testType string, args ...string) *test {
	cmd := []string{"go", "test", "-v", "./go/...", "-parallel", "1"}
	cmd = append(cmd, args...)
	return cmdTest(cmd, cwd, fmt.Sprintf("go tests (%s) in %s", testType, cwd), testType)
}

// goTestSmall returns a test which runs `go test --small` in the given cwd.
func goTestSmall(cwd string) *test {
	return goTest(cwd, testutils.SMALL_TEST, "--small", "--timeout", testutils.TIMEOUT_SMALL)
}

// goTestMedium returns a test which runs `go test --medium` in the given cwd.
func goTestMedium(cwd string) *test {
	return goTest(cwd, testutils.MEDIUM_TEST, "--medium", "--timeout", testutils.TIMEOUT_MEDIUM)
}

// goTestLarge returns a test which runs `go test --large` in the given cwd.
func goTestLarge(cwd string) *test {
	return goTest(cwd, testutils.LARGE_TEST, "--large", "--timeout", testutils.TIMEOUT_LARGE)
}

// pythonTest returns a test which runs the given Python script and fails if
// the script fails.
func pythonTest(testPath string) *test {
	return cmdTest([]string{"python", testPath}, ".", path.Base(testPath), testutils.SMALL_TEST)
}

// test is a struct which represents a single test to run.
type test struct {
	Name string
	Cmd  string
	run  func() (error, string)
	Type string
}

// Run executes the function for the given test and returns an error if it fails.
func (t test) Run() error {
	if !util.In(t.Type, testutils.TEST_TYPES) {
		sklog.Fatalf("Test %q has invalid type %q", t.Name, t.Type)
	}
	if !testutils.ShouldRun(t.Type) {
		sklog.Infof("Not running %s tests; skipping %q", t.Type, t.Name)
		return nil
	}

	defer timer.New(t.Name).Stop()
	err, output := t.run()
	if err != nil {
		return fmt.Errorf(TEST_FAILURE, t.Name, t.Cmd, err, output)
	}
	return nil
}

// Find and run tests.
func main() {
	defer common.LogPanic()
	common.Init()

	// Ensure that we're actually going to run something.
	ok := false
	for _, tt := range testutils.TEST_TYPES {
		if testutils.ShouldRun(tt) {
			ok = true
		}
	}
	if !ok {
		sklog.Errorf("Must provide --small, --medium, and/or --large. This will cause an error in the future.")
	}

	defer timer.New("Finished").Stop()

	_, filename, _, _ := runtime.Caller(0)
	rootDir := path.Dir(filename)

	// If we are running full tests make sure we have the latest
	// pdfium_test installed.
	if testutils.ShouldRun(testutils.MEDIUM_TEST) || testutils.ShouldRun(testutils.LARGE_TEST) {
		sklog.Info("Installing pdfium_test if necessary.")
		pdfiumInstall := path.Join(rootDir, "pdfium", "install_pdfium.sh")
		if err := exec.Command(pdfiumInstall).Run(); err != nil {
			sklog.Fatalf("Failed to install pdfium_test: %v", err)
		}
		sklog.Info("Latest pdfium_test installed successfully.")
	}

	// Gather all of the tests to run.
	sklog.Info("Searching for tests.")
	tests := []*test{}

	// Search for Python tests and Go dirs to test in the repo.
	if err := filepath.Walk(rootDir, func(p string, info os.FileInfo, err error) error {
		basename := path.Base(p)
		if info.IsDir() {
			// Skip some directories.
			for _, skip := range NO_CRAWL_DIR_NAMES {
				if basename == skip {
					return filepath.SkipDir
				}
			}
			for _, skip := range NO_CRAWL_REL_PATHS {
				if p == path.Join(rootDir, skip) {
					return filepath.SkipDir
				}
			}

			if basename == "go" {
				tests = append(tests, goTestSmall(path.Dir(p)))
				tests = append(tests, goTestMedium(path.Dir(p)))
				tests = append(tests, goTestLarge(path.Dir(p)))
			}
		}
		if strings.HasSuffix(basename, "_test.py") {
			tests = append(tests, pythonTest(p))
		}
		return nil
	}); err != nil {
		sklog.Fatal(err)
	}

	// Other tests.
	tests = append(tests, cmdTest([]string{"go", "vet", "./..."}, ".", "go vet", testutils.SMALL_TEST))
	tests = append(tests, cmdTest([]string{"errcheck", "-ignore", ":Close", "go.skia.org/infra/..."}, ".", "errcheck", testutils.MEDIUM_TEST))
	tests = append(tests, polylintTests()...)
	tests = append(tests, cmdTest([]string{"python", "infra/bots/recipes.py", "simulation_test"}, ".", "recipe simulation test", testutils.MEDIUM_TEST))
	tests = append(tests, cmdTest([]string{"go", "run", "infra/bots/gen_tasks.go", "--test"}, ".", "gen_tasks.go --test", testutils.SMALL_TEST))
	tests = append(tests, cmdTest([]string{"python", "infra/bots/check_cq_cfg.py"}, ".", "check CQ config", testutils.SMALL_TEST))
	tests = append(tests, cmdTest([]string{"python", "go/testutils/uncategorized_tests.py"}, ".", "uncategorized tests", testutils.SMALL_TEST))

	goimportsCmd := []string{"goimports", "-l", "."}
	tests = append(tests, &test{
		Name: "goimports",
		Cmd:  strings.Join(goimportsCmd, " "),
		run: func() (error, string) {
			command := exec.Command(goimportsCmd[0], goimportsCmd[1:]...)
			output, err := command.Output()
			outStr := strings.Trim(string(output), "\n")
			if err != nil {
				if _, err2 := exec.LookPath(goimportsCmd[0]); err2 != nil {
					return fmt.Errorf(ERR_NEED_INSTALL, goimportsCmd[0], err), outStr
				}
				// Sometimes goimports returns exit code 2, but gives no reason.
				if outStr != "" {
					return err, fmt.Sprintf("goimports output: %q", outStr)
				}
			}
			diffFiles := strings.Split(outStr, "\n")
			if len(diffFiles) > 0 && !(len(diffFiles) == 1 && diffFiles[0] == "") {
				return fmt.Errorf("goimports found diffs in the following files:\n  - %s", strings.Join(diffFiles, ",\n  - ")), outStr
			}
			return nil, ""

		},
		Type: testutils.MEDIUM_TEST,
	})

	// Run the tests.
	sklog.Infof("Found %d tests.", len(tests))
	var mutex sync.Mutex
	errors := map[string]error{}
	var wg sync.WaitGroup
	for _, t := range tests {
		wg.Add(1)
		go func(t *test) {
			defer wg.Done()
			if err := t.Run(); err != nil {
				mutex.Lock()
				errors[t.Name] = err
				mutex.Unlock()
			}
		}(t)
	}
	wg.Wait()
	if len(errors) > 0 {
		for _, e := range errors {
			sklog.Error(e)
		}
		os.Exit(1)
	}
	sklog.Info("All tests succeeded.")
}