// Copyright 2014 Team 254. All Rights Reserved.
// Author: pat@patfairbank.com (Patrick Fairbank)
//
// Methods for publishing data to and retrieving data from The Blue Alliance.

package partner

import (
	"bytes"
	"crypto/md5"
	"encoding/base64"
	"encoding/json"
	"fmt"
	"github.com/Team254/cheesy-arena-lite/model"
	"io/ioutil"
	"net/http"
	"strconv"
)

const (
	tbaBaseUrl = "https://www.thebluealliance.com"
	tbaAuthKey = "MAApv9MCuKY9MSFkXLuzTSYBCdosboxDq8Q3ujUE2Mn8PD3Nmv64uczu5Lvy0NQ3"
	AvatarsDir = "static/img/avatars"
)

type TbaClient struct {
	BaseUrl         string
	eventCode       string
	secretId        string
	secret          string
	eventNamesCache map[string]string
}

type TbaMatch struct {
	CompLevel   string                  `json:"comp_level"`
	SetNumber   int                     `json:"set_number"`
	MatchNumber int                     `json:"match_number"`
	Alliances   map[string]*TbaAlliance `json:"alliances"`
	TimeString  string                  `json:"time_string"`
	TimeUtc     string                  `json:"time_utc"`
}

type TbaAlliance struct {
	Teams      []string `json:"teams"`
	Surrogates []string `json:"surrogates"`
	Dqs        []string `json:"dqs"`
	Score      *int     `json:"score"`
}

type TbaRanking struct {
	TeamKey string `json:"team_key"`
	Rank    int    `json:"rank"`
	RP      float32
	Auto    int
	Endgame int
	Teleop  int
	Wins    int `json:"wins"`
	Losses  int `json:"losses"`
	Ties    int `json:"ties"`
	Dqs     int `json:"dqs"`
	Played  int `json:"played"`
}

type TbaRankings struct {
	Breakdowns []string     `json:"breakdowns"`
	Rankings   []TbaRanking `json:"rankings"`
}

type TbaTeam struct {
	TeamNumber int    `json:"team_number"`
	Name       string `json:"name"`
	Nickname   string `json:"nickname"`
	City       string `json:"city"`
	StateProv  string `json:"state_prov"`
	Country    string `json:"country"`
	RookieYear int    `json:"rookie_year"`
}

type TbaRobot struct {
	RobotName string `json:"robot_name"`
	Year      int    `json:"year"`
}

type TbaAward struct {
	Name      string `json:"name"`
	EventKey  string `json:"event_key"`
	Year      int    `json:"year"`
	EventName string
}

type TbaEvent struct {
	Name string `json:"name"`
}

type TbaMediaItem struct {
	Details map[string]interface{} `json:"details"`
	Type    string                 `json:"type"`
}

type TbaPublishedAward struct {
	Name    string `json:"name_str"`
	TeamKey string `json:"team_key"`
	Awardee string `json:"awardee"`
}

type elimMatchKey struct {
	elimRound int
	elimGroup int
}

type tbaElimMatchKey struct {
	compLevel string
	setNumber int
}

var doubleEliminationMatchKeyMapping = map[elimMatchKey]tbaElimMatchKey{
	{1, 1}: {"ef", 1},
	{1, 2}: {"ef", 2},
	{1, 3}: {"ef", 3},
	{1, 4}: {"ef", 4},
	{2, 1}: {"ef", 5},
	{2, 2}: {"ef", 6},
	{2, 3}: {"qf", 1},
	{2, 4}: {"qf", 2},
	{3, 1}: {"qf", 3},
	{3, 2}: {"qf", 4},
	{4, 1}: {"sf", 1},
	{4, 2}: {"sf", 2},
	{5, 1}: {"f", 1},
	{6, 1}: {"f", 2},
}

func NewTbaClient(eventCode, secretId, secret string) *TbaClient {
	return &TbaClient{BaseUrl: tbaBaseUrl, eventCode: eventCode, secretId: secretId, secret: secret,
		eventNamesCache: make(map[string]string)}
}

func (client *TbaClient) GetTeam(teamNumber int) (*TbaTeam, error) {
	path := fmt.Sprintf("/api/v3/team/%s", getTbaTeam(teamNumber))
	resp, err := client.getRequest(path)
	if err != nil {
		return nil, err
	}

	// Get the response and handle errors
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	var teamData TbaTeam
	err = json.Unmarshal(body, &teamData)

	return &teamData, err
}

func (client *TbaClient) GetRobotName(teamNumber int, year int) (string, error) {
	path := fmt.Sprintf("/api/v3/team/%s/robots", getTbaTeam(teamNumber))
	resp, err := client.getRequest(path)
	if err != nil {
		return "", err
	}

	// Get the response and handle errors
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}

	var robots []*TbaRobot
	err = json.Unmarshal(body, &robots)
	if err != nil {
		return "", err
	}
	for _, robot := range robots {
		if robot.Year == year {
			return robot.RobotName, nil
		}
	}
	return "", nil
}

func (client *TbaClient) GetTeamAwards(teamNumber int) ([]*TbaAward, error) {
	path := fmt.Sprintf("/api/v3/team/%s/awards", getTbaTeam(teamNumber))
	resp, err := client.getRequest(path)
	if err != nil {
		return nil, err
	}

	// Get the response and handle errors
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}

	var awards []*TbaAward
	err = json.Unmarshal(body, &awards)
	if err != nil {
		return nil, err
	}

	for _, award := range awards {
		if _, ok := client.eventNamesCache[award.EventKey]; !ok {
			client.eventNamesCache[award.EventKey], err = client.getEventName(award.EventKey)
			if err != nil {
				return nil, err
			}
		}
		award.EventName = client.eventNamesCache[award.EventKey]
	}

	return awards, nil
}

func (client *TbaClient) DownloadTeamAvatar(teamNumber, year int) error {
	path := fmt.Sprintf("/api/v3/team/%s/media/%d", getTbaTeam(teamNumber), year)
	resp, err := client.getRequest(path)
	if err != nil {
		return err
	}

	// Get the response and handle errors
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return err
	}

	var mediaItems []*TbaMediaItem
	err = json.Unmarshal(body, &mediaItems)
	if err != nil {
		return err
	}

	for _, item := range mediaItems {
		if item.Type == "avatar" {
			base64String, ok := item.Details["base64Image"].(string)
			if !ok {
				return fmt.Errorf("Could not interpret avatar response from TBA: %v", item)
			}
			avatarBytes, err := base64.StdEncoding.DecodeString(base64String)
			if err != nil {
				return err
			}

			// Store the avatar to disk as a PNG file.
			avatarPath := fmt.Sprintf("%s/%d.png", AvatarsDir, teamNumber)
			ioutil.WriteFile(avatarPath, avatarBytes, 0644)
			return nil
		}
	}

	return fmt.Errorf("No avatar found for team %d in year %d.", teamNumber, year)
}

// Uploads the event team list to The Blue Alliance.
func (client *TbaClient) PublishTeams(database *model.Database) error {
	teams, err := database.GetAllTeams()
	if err != nil {
		return err
	}

	// Build a JSON array of TBA-format team keys (e.g. "frc254").
	teamKeys := make([]string, len(teams))
	for i, team := range teams {
		teamKeys[i] = getTbaTeam(team.Id)
	}
	jsonBody, err := json.Marshal(teamKeys)
	if err != nil {
		return err
	}

	resp, err := client.postRequest("team_list", "update", jsonBody)
	if err != nil {
		return err
	}
	if resp.StatusCode != 200 {
		defer resp.Body.Close()
		body, _ := ioutil.ReadAll(resp.Body)
		return fmt.Errorf("Got status code %d from TBA: %s", resp.StatusCode, body)
	}
	return nil
}

// Uploads the qualification and elimination match schedule and results to The Blue Alliance.
func (client *TbaClient) PublishMatches(database *model.Database) error {
	qualMatches, err := database.GetMatchesByType("qualification")
	if err != nil {
		return err
	}
	elimMatches, err := database.GetMatchesByType("elimination")
	if err != nil {
		return err
	}
	eventSettings, err := database.GetEventSettings()
	if err != nil {
		return err
	}
	matches := append(qualMatches, elimMatches...)
	tbaMatches := make([]TbaMatch, len(matches))

	// Build a JSON array of TBA-format matches.
	for i, match := range matches {
		matchNumber, _ := strconv.Atoi(match.DisplayName)

		// Fill in scores if the match has been played.
		var redScoreSummary, blueScoreSummary int
		var redScore, blueScore *int
		if match.IsComplete() {
			matchResult, err := database.GetMatchResultForMatch(match.Id)
			if err != nil {
				return err
			}
			if matchResult != nil {
				redScoreSummary = matchResult.RedScore.AutoPoints +
					matchResult.RedScore.TeleopPoints +
					matchResult.RedScore.EndgamePoints
				blueScoreSummary = matchResult.BlueScore.AutoPoints +
					matchResult.BlueScore.TeleopPoints +
					matchResult.BlueScore.EndgamePoints
				redScore = &redScoreSummary
				blueScore = &blueScoreSummary
			}
		}
		alliances := make(map[string]*TbaAlliance)
		alliances["red"] = createTbaAlliance([3]int{match.Red1, match.Red2, match.Red3}, [3]bool{match.Red1IsSurrogate,
			match.Red2IsSurrogate, match.Red3IsSurrogate}, redScore)
		alliances["blue"] = createTbaAlliance([3]int{match.Blue1, match.Blue2, match.Blue3},
			[3]bool{match.Blue1IsSurrogate, match.Blue2IsSurrogate, match.Blue3IsSurrogate}, blueScore)

		tbaMatches[i] = TbaMatch{"qm", 0, matchNumber, alliances, match.Time.Local().Format("3:04 PM"),
			match.Time.UTC().Format("2006-01-02T15:04:05")}
		if match.Type == "elimination" {
			setElimMatchKey(&tbaMatches[i], &match, eventSettings.ElimType)
		}
	}
	jsonBody, err := json.Marshal(tbaMatches)
	if err != nil {
		return err
	}

	resp, err := client.postRequest("matches", "update", jsonBody)
	if err != nil {
		return err
	}
	if resp.StatusCode != 200 {
		defer resp.Body.Close()
		body, _ := ioutil.ReadAll(resp.Body)
		return fmt.Errorf("Got status code %d from TBA: %s", resp.StatusCode, body)
	}
	return nil
}

// Uploads the team standings to The Blue Alliance.
func (client *TbaClient) PublishRankings(database *model.Database) error {
	rankings, err := database.GetAllRankings()
	if err != nil {
		return err
	}

	// Build a JSON object of TBA-format rankings.
	breakdowns := []string{"RP", "Auto", "Endgame", "Teleop"}
	tbaRankings := make([]TbaRanking, len(rankings))
	for i, ranking := range rankings {
		tbaRankings[i] = TbaRanking{
			TeamKey: getTbaTeam(ranking.TeamId),
			Rank:    ranking.Rank,
			RP:      float32(ranking.RankingPoints) / float32(ranking.Played),
			Auto:    ranking.AutoPoints,
			Endgame: ranking.EndgamePoints,
			Teleop:  ranking.TeleopPoints,
			Wins:    ranking.Wins,
			Losses:  ranking.Losses,
			Ties:    ranking.Ties,
			Played:  ranking.Played,
		}
	}
	jsonBody, err := json.Marshal(TbaRankings{breakdowns, tbaRankings})
	if err != nil {
		return err
	}

	resp, err := client.postRequest("rankings", "update", jsonBody)
	if err != nil {
		return err
	}
	if resp.StatusCode != 200 {
		defer resp.Body.Close()
		body, _ := ioutil.ReadAll(resp.Body)
		return fmt.Errorf("Got status code %d from TBA: %s", resp.StatusCode, body)
	}
	return nil
}

// Uploads the alliances selection results to The Blue Alliance.
func (client *TbaClient) PublishAlliances(database *model.Database) error {
	alliances, err := database.GetAllAlliances()
	if err != nil {
		return err
	}

	// Build a JSON object of TBA-format alliances.
	tbaAlliances := make([][]string, len(alliances))
	for i, alliance := range alliances {
		for _, allianceTeamId := range alliance.TeamIds {
			tbaAlliances[i] = append(tbaAlliances[i], getTbaTeam(allianceTeamId))
		}
	}
	jsonBody, err := json.Marshal(tbaAlliances)
	if err != nil {
		return err
	}

	resp, err := client.postRequest("alliance_selections", "update", jsonBody)
	if err != nil {
		return err
	}
	if resp.StatusCode != 200 {
		defer resp.Body.Close()
		body, _ := ioutil.ReadAll(resp.Body)
		return fmt.Errorf("Got status code %d from TBA: %s", resp.StatusCode, body)
	}
	return nil
}

// Clears out the existing match data on The Blue Alliance for the event.
func (client *TbaClient) DeletePublishedMatches() error {
	resp, err := client.postRequest("matches", "delete_all", []byte(client.eventCode))
	if err != nil {
		return err
	}
	if resp.StatusCode != 200 {
		defer resp.Body.Close()
		body, _ := ioutil.ReadAll(resp.Body)
		return fmt.Errorf("Got status code %d from TBA: %s", resp.StatusCode, body)
	}
	return nil
}

func (client *TbaClient) getEventName(eventCode string) (string, error) {
	path := fmt.Sprintf("/api/v3/event/%s", eventCode)
	resp, err := client.getRequest(path)
	if err != nil {
		return "", err
	}

	// Get the response and handle errors
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}

	var event TbaEvent
	err = json.Unmarshal(body, &event)
	if err != nil {
		return "", err
	}

	return event.Name, err
}

// Converts an integer team number into the "frcXXXX" format TBA expects.
func getTbaTeam(team int) string {
	return fmt.Sprintf("frc%d", team)
}

// Sends a GET request to the TBA API.
func (client *TbaClient) getRequest(path string) (*http.Response, error) {
	url := client.BaseUrl + path

	// Make an HTTP GET request with the TBA auth headers.
	httpClient := &http.Client{}
	req, err := http.NewRequest("GET", url, nil)
	if err != nil {
		return nil, err
	}
	req.Header.Set("X-TBA-Auth-Key", tbaAuthKey)
	return httpClient.Do(req)
}

// Signs the request and sends it to the TBA API.
func (client *TbaClient) postRequest(resource string, action string, body []byte) (*http.Response, error) {
	path := fmt.Sprintf("/api/trusted/v1/event/%s/%s/%s", client.eventCode, resource, action)
	signature := fmt.Sprintf("%x", md5.Sum(append([]byte(client.secret+path), body...)))

	httpClient := &http.Client{}
	request, err := http.NewRequest("POST", client.BaseUrl+path, bytes.NewReader(body))
	if err != nil {
		return nil, err
	}
	request.Header.Add("X-TBA-Auth-Id", client.secretId)
	request.Header.Add("X-TBA-Auth-Sig", signature)
	return httpClient.Do(request)
}

func createTbaAlliance(teamIds [3]int, surrogates [3]bool, score *int) *TbaAlliance {
	alliance := TbaAlliance{Surrogates: []string{}, Dqs: []string{}, Score: score}
	for i, teamId := range teamIds {
		teamKey := getTbaTeam(teamId)
		alliance.Teams = append(alliance.Teams, teamKey)
		if surrogates[i] {
			alliance.Surrogates = append(alliance.Surrogates, teamKey)
		}
	}

	return &alliance
}

// Uploads the awards to The Blue Alliance.
func (client *TbaClient) PublishAwards(database *model.Database) error {
	awards, err := database.GetAllAwards()
	if err != nil {
		return err
	}

	// Build a JSON array of TBA-format award models.
	tbaAwards := make([]TbaPublishedAward, len(awards))
	for i, award := range awards {
		tbaAwards[i].Name = award.AwardName
		tbaAwards[i].TeamKey = getTbaTeam(award.TeamId)
		tbaAwards[i].Awardee = award.PersonName
	}
	jsonBody, err := json.Marshal(tbaAwards)
	if err != nil {
		return err
	}

	resp, err := client.postRequest("awards", "update", jsonBody)
	if err != nil {
		return err
	}
	if resp.StatusCode != 200 {
		defer resp.Body.Close()
		body, _ := ioutil.ReadAll(resp.Body)
		return fmt.Errorf("Got status code %d from TBA: %s", resp.StatusCode, body)
	}
	return nil
}

// Sets the match key attributes on TbaMatch based on the match and bracket type.
func setElimMatchKey(tbaMatch *TbaMatch, match *model.Match, elimType string) {
	if elimType == "single" {
		tbaMatch.CompLevel = map[int]string{1: "ef", 2: "qf", 3: "sf", 4: "f"}[match.ElimRound]
		tbaMatch.SetNumber = match.ElimGroup
		tbaMatch.MatchNumber = match.ElimInstance
	} else if elimType == "double" {
		if tbaKey, ok := doubleEliminationMatchKeyMapping[elimMatchKey{match.ElimRound, match.ElimGroup}]; ok {
			tbaMatch.CompLevel = tbaKey.compLevel
			tbaMatch.SetNumber = tbaKey.setNumber
		}
		tbaMatch.MatchNumber = match.ElimInstance
	}
}