// Copyright 2014 The Gogs Authors. All rights reserved.
// Use of this source code is governed by a MIT-style
// license that can be found in the LICENSE file.

package models

import (
	"encoding/json"
	"errors"
	"fmt"
	"path"
	"regexp"
	"strings"
	"time"
	"unicode"

	"github.com/gogits/gogs/modules/base"
	"github.com/gogits/gogs/modules/git"
	"github.com/gogits/gogs/modules/log"
	"github.com/gogits/gogs/modules/setting"
)

type ActionType int

const (
	CREATE_REPO   ActionType = iota + 1 // 1
	DELETE_REPO                         // 2
	STAR_REPO                           // 3
	FOLLOW_REPO                         // 4
	COMMIT_REPO                         // 5
	CREATE_ISSUE                        // 6
	PULL_REQUEST                        // 7
	TRANSFER_REPO                       // 8
	PUSH_TAG                            // 9
	COMMENT_ISSUE                       // 10
)

var (
	ErrNotImplemented = errors.New("Not implemented yet")
)

var (
	// Same as Github. See https://help.github.com/articles/closing-issues-via-commit-messages
	IssueKeywords    = []string{"close", "closes", "closed", "fix", "fixes", "fixed", "resolve", "resolves", "resolved"}
	IssueKeywordsPat *regexp.Regexp
)

func init() {
	IssueKeywordsPat = regexp.MustCompile(fmt.Sprintf(`(?i)(?:%s) \S+`, strings.Join(IssueKeywords, "|")))
}

// Action represents user operation type and other information to repository.,
// it implemented interface base.Actioner so that can be used in template render.
type Action struct {
	Id           int64
	UserId       int64 // Receiver user id.
	OpType       ActionType
	ActUserId    int64  // Action user id.
	ActUserName  string // Action user name.
	ActEmail     string
	RepoId       int64
	RepoUserName string
	RepoName     string
	RefName      string
	IsPrivate    bool      `xorm:"NOT NULL DEFAULT false"`
	Content      string    `xorm:"TEXT"`
	Created      time.Time `xorm:"created"`
}

func (a Action) GetOpType() int {
	return int(a.OpType)
}

func (a Action) GetActUserName() string {
	return a.ActUserName
}

func (a Action) GetActEmail() string {
	return a.ActEmail
}

func (a Action) GetRepoUserName() string {
	return a.RepoUserName
}

func (a Action) GetRepoName() string {
	return a.RepoName
}

func (a Action) GetRepoLink() string {
	return path.Join(a.RepoUserName, a.RepoName)
}

func (a Action) GetBranch() string {
	return a.RefName
}

func (a Action) GetContent() string {
	return a.Content
}

func (a Action) GetCreate() time.Time {
	return a.Created
}

func (a Action) GetIssueInfos() []string {
	return strings.SplitN(a.Content, "|", 2)
}

func updateIssuesCommit(userId, repoId int64, repoUserName, repoName string, commits []*base.PushCommit) error {
	for _, c := range commits {
		refs := IssueKeywordsPat.FindAllString(c.Message, -1)

		for _, ref := range refs {
			ref := ref[strings.IndexByte(ref, byte(' '))+1:]
			ref = strings.TrimRightFunc(ref, func(c rune) bool {
				return !unicode.IsDigit(c)
			})

			if len(ref) == 0 {
				continue
			}

			// Add repo name if missing
			if ref[0] == '#' {
				ref = fmt.Sprintf("%s/%s%s", repoUserName, repoName, ref)
			} else if strings.Contains(ref, "/") == false {
				// We don't support User#ID syntax yet
				// return ErrNotImplemented

				continue
			}

			issue, err := GetIssueByRef(ref)

			if err != nil {
				return err
			}

			url := fmt.Sprintf("/%s/%s/commit/%s", repoUserName, repoName, c.Sha1)
			message := fmt.Sprintf(`<a href="%s">%s</a>`, url, c.Message)

			if _, err = CreateComment(userId, issue.RepoId, issue.Id, 0, 0, COMMIT, message, nil); err != nil {
				return err
			}

			if issue.RepoId == repoId {
				if issue.IsClosed {
					continue
				}

				issue.IsClosed = true

				if err = UpdateIssue(issue); err != nil {
					return err
				}

				if err = ChangeMilestoneIssueStats(issue); err != nil {
					return err
				}

				// If commit happened in the referenced repository, it means the issue can be closed.
				if _, err = CreateComment(userId, repoId, issue.Id, 0, 0, CLOSE, "", nil); err != nil {
					return err
				}
			}
		}
	}

	return nil
}

// CommitRepoAction adds new action for committing repository.
func CommitRepoAction(userId, repoUserId int64, userName, actEmail string,
	repoId int64, repoUserName, repoName string, refFullName string, commit *base.PushCommits) error {

	opType := COMMIT_REPO
	// Check it's tag push or branch.
	if strings.HasPrefix(refFullName, "refs/tags/") {
		opType = PUSH_TAG
		commit = &base.PushCommits{}
	}

	refName := git.RefEndName(refFullName)

	bs, err := json.Marshal(commit)
	if err != nil {
		return errors.New("action.CommitRepoAction(json): " + err.Error())
	}

	// Change repository bare status and update last updated time.
	repo, err := GetRepositoryByName(repoUserId, repoName)
	if err != nil {
		return errors.New("action.CommitRepoAction(GetRepositoryByName): " + err.Error())
	}
	repo.IsBare = false
	if err = UpdateRepository(repo); err != nil {
		return errors.New("action.CommitRepoAction(UpdateRepository): " + err.Error())
	}

	err = updateIssuesCommit(userId, repoId, repoUserName, repoName, commit.Commits)

	if err != nil {
		log.Debug("action.CommitRepoAction(updateIssuesCommit): ", err)
	}

	if err = NotifyWatchers(&Action{ActUserId: userId, ActUserName: userName, ActEmail: actEmail,
		OpType: opType, Content: string(bs), RepoId: repoId, RepoUserName: repoUserName,
		RepoName: repoName, RefName: refName,
		IsPrivate: repo.IsPrivate}); err != nil {
		return errors.New("action.CommitRepoAction(NotifyWatchers): " + err.Error())

	}
	//qlog.Info("action.CommitRepoAction(end): %d/%s", repoUserId, repoName)

	// New push event hook.
	if err := repo.GetOwner(); err != nil {
		return errors.New("action.CommitRepoAction(GetOwner): " + err.Error())
	}

	ws, err := GetActiveWebhooksByRepoId(repoId)
	if err != nil {
		return errors.New("action.CommitRepoAction(GetWebhooksByRepoId): " + err.Error())
	} else if len(ws) == 0 {
		return nil
	}

	repoLink := fmt.Sprintf("%s%s/%s", setting.AppUrl, repoUserName, repoName)
	commits := make([]*PayloadCommit, len(commit.Commits))
	for i, cmt := range commit.Commits {
		commits[i] = &PayloadCommit{
			Id:      cmt.Sha1,
			Message: cmt.Message,
			Url:     fmt.Sprintf("%s/commit/%s", repoLink, cmt.Sha1),
			Author: &PayloadAuthor{
				Name:  cmt.AuthorName,
				Email: cmt.AuthorEmail,
			},
		}
	}
	p := &Payload{
		Ref:     refFullName,
		Commits: commits,
		Repo: &PayloadRepo{
			Id:          repo.Id,
			Name:        repo.LowerName,
			Url:         repoLink,
			Description: repo.Description,
			Website:     repo.Website,
			Watchers:    repo.NumWatches,
			Owner: &PayloadAuthor{
				Name:  repoUserName,
				Email: actEmail,
			},
			Private: repo.IsPrivate,
		},
		Pusher: &PayloadAuthor{
			Name:  repo.Owner.LowerName,
			Email: repo.Owner.Email,
		},
	}

	for _, w := range ws {
		w.GetEvent()
		if !w.HasPushEvent() {
			continue
		}

		p.Secret = w.Secret
		CreateHookTask(&HookTask{
			Type:        WEBHOOK,
			Url:         w.Url,
			Payload:     p,
			ContentType: w.ContentType,
			IsSsl:       w.IsSsl,
		})
	}
	return nil
}

// NewRepoAction adds new action for creating repository.
func NewRepoAction(u *User, repo *Repository) (err error) {
	if err = NotifyWatchers(&Action{ActUserId: u.Id, ActUserName: u.Name, ActEmail: u.Email,
		OpType: CREATE_REPO, RepoId: repo.Id, RepoUserName: repo.Owner.Name, RepoName: repo.Name,
		IsPrivate: repo.IsPrivate}); err != nil {
		log.Error(4, "NotifyWatchers: %d/%s", u.Id, repo.Name)
		return err
	}

	log.Trace("action.NewRepoAction: %s/%s", u.Name, repo.Name)
	return err
}

// TransferRepoAction adds new action for transfering repository.
func TransferRepoAction(u, newUser *User, repo *Repository) (err error) {
	if err = NotifyWatchers(&Action{ActUserId: u.Id, ActUserName: u.Name, ActEmail: u.Email,
		OpType: TRANSFER_REPO, RepoId: repo.Id, RepoName: repo.Name, Content: newUser.Name,
		IsPrivate: repo.IsPrivate}); err != nil {
		log.Error(4, "NotifyWatchers: %d/%s", u.Id, repo.Name)
		return err
	}

	log.Trace("action.TransferRepoAction: %s/%s", u.Name, repo.Name)
	return err
}

// GetFeeds returns action list of given user in given context.
func GetFeeds(uid, offset int64, isProfile bool) ([]*Action, error) {
	actions := make([]*Action, 0, 20)
	sess := x.Limit(20, int(offset)).Desc("id").Where("user_id=?", uid)
	if isProfile {
		sess.Where("is_private=?", false).And("act_user_id=?", uid)
	}
	err := sess.Find(&actions)
	return actions, err
}