package api

import (
	"bytes"
	"code.gitea.io/gitea/modules/structs"
	"encoding/json"
	"git.lumeweb.com/LumeWeb/gitea-github-proxy/config"
	"git.lumeweb.com/LumeWeb/gitea-github-proxy/db/model"
	"github.com/google/go-github/v59/github"
	"go.uber.org/zap"
	"gorm.io/gorm"
	"io"
	"net/http"
	"time"
)

type WebhookManager struct {
	config *config.Config
	db     *gorm.DB
	logger *zap.Logger
}

type IncomingWebhookData struct {
	Headers http.Header
}

func NewWebhookManager(cfg *config.Config, db *gorm.DB, logger *zap.Logger) *WebhookManager {
	return &WebhookManager{config: cfg, db: db, logger: logger}
}

func (whm *WebhookManager) HandlePullRequest(request *structs.PullRequestPayload, r *http.Request) {
	// Mapping the sender
	sender := &github.User{
		Login:     &request.Sender.UserName,
		ID:        &request.Sender.ID,
		AvatarURL: &request.Sender.AvatarURL,
		Name:      &request.Sender.FullName,
		Email:     &request.Sender.Email,
		SiteAdmin: &request.Sender.IsAdmin,
	}
	repo := &github.Repository{
		ID:               int64Ptr(request.Repository.ID),
		Name:             stringPtr(request.Repository.Name),
		FullName:         stringPtr(request.Repository.FullName),
		Description:      stringPtr(request.Repository.Description),
		Homepage:         stringPtr(request.Repository.Website),
		HTMLURL:          stringPtr(request.Repository.HTMLURL),
		CloneURL:         stringPtr(request.Repository.CloneURL),
		GitURL:           stringPtr(request.Repository.CloneURL),
		SSHURL:           stringPtr(request.Repository.SSHURL),
		DefaultBranch:    stringPtr(request.Repository.DefaultBranch),
		CreatedAt:        timePtr(request.Repository.Created),
		UpdatedAt:        timePtr(request.Repository.Updated),
		Private:          boolPtr(request.Repository.Private),
		Fork:             boolPtr(request.Repository.Fork),
		Size:             intPtr(request.Repository.Size),
		StargazersCount:  intPtr(request.Repository.Stars),
		SubscribersCount: intPtr(request.Repository.Watchers),
		ForksCount:       intPtr(request.Repository.Forks),
		Watchers:         intPtr(request.Repository.Watchers),
		WatchersCount:    intPtr(request.Repository.Stars),
		OpenIssuesCount:  intPtr(request.Repository.OpenIssues),
		Archived:         boolPtr(request.Repository.Archived),
	}

	pr := &github.PullRequest{
		ID:             int64Ptr(request.PullRequest.ID),
		Number:         intPtr(int(request.PullRequest.Index)),
		State:          stringPtr(string(request.PullRequest.State)),
		Title:          stringPtr(request.PullRequest.Title),
		Body:           stringPtr(request.PullRequest.Body),
		CreatedAt:      timePtr(*request.PullRequest.Created),
		UpdatedAt:      timePtr(*request.PullRequest.Updated),
		ClosedAt:       timePtrIfNotNil(request.PullRequest.Closed),
		MergedAt:       timePtrIfNotNil(request.PullRequest.Merged),
		Merged:         boolPtr(request.PullRequest.HasMerged),
		Mergeable:      boolPtr(request.PullRequest.Mergeable),
		MergeCommitSHA: request.PullRequest.MergedCommitID,
		URL:            stringPtr(request.PullRequest.URL),
		HTMLURL:        stringPtr(request.PullRequest.HTMLURL),
		DiffURL:        stringPtr(request.PullRequest.DiffURL),
		PatchURL:       stringPtr(request.PullRequest.PatchURL),
		Comments:       intPtr(request.PullRequest.Comments),
		Assignee:       convertUser(request.PullRequest.Assignee),
		Assignees:      convertUsers(request.PullRequest.Assignees),
		Milestone:      convertMilestone(request.PullRequest.Milestone),
		Labels:         convertLabels(request.PullRequest.Labels),
	}

	// Convert PR branch info
	if request.PullRequest.Head != nil {
		pr.Head = convertPRBranch(request.PullRequest.Head)
	}
	if request.PullRequest.Base != nil {
		pr.Base = convertPRBranch(request.PullRequest.Base)
	}

	changes := &github.EditChange{
		Title: &github.EditTitle{
			From: stringPtr(request.Changes.Title.From),
		},
		Body: &github.EditBody{
			From: stringPtr(request.Changes.Body.From),
		},
		Base: &github.EditBase{
			Ref: &github.EditRef{
				From: stringPtr(request.Changes.Ref.From),
			},
		},
	}

	ghEvent := &github.PullRequestEvent{
		Action:      stringPtr(string(request.Action)),
		Number:      numberPtr(int(request.Index)),
		PullRequest: pr,
		Changes:     changes,
		Repo:        repo,
		Sender:      sender,
	}
	githubAction := ""

	switch request.Action {
	case structs.HookIssueOpened:
		githubAction = "opened"
	case structs.HookIssueClosed:
		githubAction = "closed"
	case structs.HookIssueReOpened:
		githubAction = "reopened"
	case structs.HookIssueEdited:
		githubAction = "edited"
	case structs.HookIssueAssigned:
		githubAction = "assigned"
	case structs.HookIssueUnassigned:
		githubAction = "unassigned"
	case structs.HookIssueLabelUpdated:
		// GitHub does not have a direct "label_updated" event; use "labeled" as the closest action
		githubAction = "labeled" // Assuming you handle the update as adding a label
	case structs.HookIssueLabelCleared:
		// GitHub does not have a direct "label_cleared" event; use "unlabeled" as the closest action
		githubAction = "unlabeled" // Assuming you handle the clearing as removing a label
	case structs.HookIssueSynchronized:
		githubAction = "synchronize"
	case structs.HookIssueMilestoned:
		githubAction = "milestoned"
	case structs.HookIssueDemilestoned:
		githubAction = "demilestoned"
	case structs.HookIssueReviewed:
		// GitHub does not have a direct "reviewed" event for PRs; this might be closest to a review submitted
		githubAction = "review_submitted" // This is not a direct GitHub event, consider how best to map this action
	case structs.HookIssueReviewRequested:
		githubAction = "review_requested"
	case structs.HookIssueReviewRequestRemoved:
		githubAction = "review_request_removed"
	default:
		// Fallback for any unhandled actions
		githubAction = "unknown_action"
	}
	r.Header.Set("X-GitHub-Event", githubAction)

	whm.sendWebhooks(ghEvent, r)
}

func stringPtr(s string) *string {
	return &s
}

func numberPtr(n int) *int {
	return &n
}

func intPtr(n int) *int {
	return &n
}

func int64Ptr(n int64) *int64 {
	return &n
}

func boolPtr(b bool) *bool {
	return &b
}

func timePtr(t time.Time) *github.Timestamp {
	timestamp := github.Timestamp{Time: t}
	return &timestamp
}

func timePtrIfNotNil(t *time.Time) *github.Timestamp {
	if t == nil {
		return nil
	}
	return timePtr(*t)
}

func convertUser(user *structs.User) *github.User {
	if user == nil {
		return nil
	}
	return &github.User{
		Login: stringPtr(user.UserName),
		ID:    int64Ptr(user.ID),
	}
}

func convertUsers(users []*structs.User) []*github.User {
	var ghUsers []*github.User
	for _, user := range users {
		ghUsers = append(ghUsers, convertUser(user))
	}
	return ghUsers
}

func convertMilestone(milestone *structs.Milestone) *github.Milestone {
	if milestone == nil {
		return nil
	}
	return &github.Milestone{
		Title: stringPtr(milestone.Title),
	}
}

func convertLabels(labels []*structs.Label) []*github.Label {
	var ghLabels []*github.Label
	for _, label := range labels {
		ghLabels = append(ghLabels, &github.Label{
			Name: stringPtr(label.Name),
		})
	}
	return ghLabels
}

func convertPRBranch(branch *structs.PRBranchInfo) *github.PullRequestBranch {
	return &github.PullRequestBranch{
		Label: stringPtr(branch.Name),
		Ref:   stringPtr(branch.Ref),
		SHA:   stringPtr(branch.Sha),
	}
}

func (whm *WebhookManager) sendWebhooks(request interface{}, r *http.Request) {
	var apps []model.Apps
	result := whm.db.Find(&apps)
	if result.Error != nil {
		whm.logger.Error("Failed to query apps", zap.Error(result.Error))
		return
	}
	for _, app := range apps {
		go func(app model.Apps) {
			payloadBytes, err := json.Marshal(request)
			if err != nil {
				whm.logger.Error("Failed to marshal payload", zap.Error(err))
				return
			}

			req, err := http.NewRequest("POST", app.WebhookUrl, bytes.NewBuffer(payloadBytes))
			if err != nil {
				whm.logger.Error("Failed to create request", zap.Error(err), zap.String("url", app.WebhookUrl))
				return
			}

			req.Header.Set("Content-Type", "application/json")

			for key, values := range r.Header {
				for _, value := range values {
					req.Header.Add(key, value)
				}
			}

			payload := getWebhookData(r, whm.logger)
			signature := generatePayloadSignature(payload, app.WebhookSecret)
			req.Header.Add("X-Hub-Signature-256", signature)

			client := &http.Client{}
			resp, err := client.Do(req)
			if err != nil {
				whm.logger.Error("Failed to send webhook", zap.Error(err), zap.String("url", app.WebhookUrl))
				return
			}
			defer func(Body io.ReadCloser) {
				err := Body.Close()
				if err != nil {
					whm.logger.Error("Failed to close response body", zap.Error(err))
				}
			}(resp.Body)

			if resp.StatusCode >= 200 && resp.StatusCode < 300 {
				whm.logger.Info("Webhook sent successfully", zap.String("url", app.WebhookUrl))
			} else {
				whm.logger.Error("Webhook failed", zap.String("url", app.WebhookUrl), zap.Int("status", resp.StatusCode))
			}
		}(app)
	}

}