// Copyright (C) 2016 Sebastian 'tokkee' Harl <sh@tokkee.org>
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
// OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
// WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
// OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
// ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

package ui_test

import (
	"fmt"
	"io/ioutil"
	"log"
	"net/http"
	"net/url"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"google.golang.org/grpc"
)

var (
	server string
	ui     string

	// TODO: probe for unused ports
	serverPort = "50051"
	uiPort     = "9999"
)

func init() {
	gopath := os.Getenv("GOPATH")
	if gopath == "" {
		panic("GOPATH not set")
	}

	server = filepath.Join(gopath, "bin", "server")
	ui = filepath.Join(gopath, "bin", "ui")

	for _, path := range []string{server, ui} {
		if _, err := os.Stat(path); err != nil {
			if !os.IsNotExist(err) {
				panic(err)
			}
			panic(fmt.Sprintf("%s and/or %s not found; run 'go install tokkee.org/go-talk/grpc/server tokkee.org/go-talk/grpc/ui'", server, ui))
		}
	}
}

// setup sets up a Backend test instance and UI and returns the UI address and
// a cleanup function to be called when done.
func setup() (string, func(), error) {
	srv := exec.Command(server, "--listen=:"+serverPort)
	if err := srv.Start(); err != nil {
		return "", nil, fmt.Errorf("failed to start server: %v", err)
	}
	// Wait for the server to be ready.
	conn, err := grpc.Dial("localhost:"+serverPort, grpc.WithInsecure())
	if err != nil {
		srv.Process.Kill()
		return "", nil, fmt.Errorf("failed to connect to server: %v", err)
	}
	conn.Close()

	u := exec.Command(ui, "--listen=:"+uiPort, "--backend=localhost:"+serverPort)
	if err := u.Start(); err != nil {
		srv.Process.Kill()
		return "", nil, fmt.Errorf("failed to start UI: %v", err)
	}
	// Wait for the UI to be ready.
	for {
		if _, err := http.Get("http://localhost:" + uiPort + "/query"); err == nil {
			break
		}
		time.Sleep(10 * time.Millisecond)
	}

	return "http://localhost:" + uiPort, func() {
		if err := u.Process.Kill(); err != nil {
			log.Printf("Failed to kill UI process: %v", err)
		}
		u.Wait()

		if err := srv.Process.Kill(); err != nil {
			log.Printf("Failed to kill server process: %v", err)
		}
		srv.Wait()
	}, nil
}

// TestQuery runs sample queries against the /query endpoint of the UI and
// checks the results.
func TestQuery(t *testing.T) {
	addr, cleanup, err := setup()
	if err != nil {
		t.Fatalf("Setup failed: %v", err)
	}
	defer cleanup()

	for _, test := range []struct {
		query    string
		status   int
		expected []string
	}{
		{
			query:  "CounT 123456",
			status: 200,
			expected: []string{
				"<b>CounT 123456 =></b> COUNT: 6",
			},
		},
		{
			query:  "count abc",
			status: 200,
			expected: []string{
				"<b>count abc =></b> COUNT: 3",
			},
		},
		{
			query:  "count multiple words are supported as well; RANDOM 7; RANDOM 4",
			status: 200,
			expected: []string{
				"<b>count multiple words are supported as well =></b> COUNT: 36",
				"<b>RANDOM 7 =></b> RANDOM: 4",
				"<b>RANDOM 4 =></b> RANDOM: 0",
			},
		},
		{
			query:  "RANDOM NAN",
			status: 400,
		},
		{
			query:  "COUNT",
			status: 400,
		},
		{
			query:  "INVALID COMMAND",
			status: 400,
		},
	} {
		params := make(url.Values)
		params.Add("q", test.query)
		res, err := http.PostForm(addr+"/query", params)
		if err != nil {
			t.Errorf("PostForm(%q, %v) = %v", addr+"/query", params, err)
			continue
		}
		defer res.Body.Close()

		raw, err := ioutil.ReadAll(res.Body)
		if err != nil {
			t.Errorf("Failed to read response body: %v", err)
			continue
		}
		body := string(raw)

		ok := true
		for _, expected := range test.expected {
			if !strings.Contains(body, expected) {
				ok = false
				break
			}
		}
		if res.StatusCode != test.status || !ok {
			t.Errorf("POST(%q, %v) = %v:\n%s\nwant status=%d; matches=%v", addr+"/query", params, res, body, test.status, test.expected)
		}
	}
}