// Copyright 2024 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package org

import (
	"context"
	"fmt"
	"strings"

	"code.gitea.io/gitea/models/db"
	git_model "code.gitea.io/gitea/models/git"
	issues_model "code.gitea.io/gitea/models/issues"
	"code.gitea.io/gitea/models/organization"
	access_model "code.gitea.io/gitea/models/perm/access"
	repo_model "code.gitea.io/gitea/models/repo"
	user_model "code.gitea.io/gitea/models/user"
	"code.gitea.io/gitea/modules/graceful"
	"code.gitea.io/gitea/modules/log"
	"code.gitea.io/gitea/modules/setting"
	"code.gitea.io/gitea/modules/util"
	repo_service "code.gitea.io/gitea/services/repository"

	"xorm.io/builder"
)

// NewTeam creates a record of new team.
// It's caller's responsibility to assign organization ID.
func NewTeam(ctx context.Context, t *organization.Team) (err error) {
	if len(t.Name) == 0 {
		return util.NewInvalidArgumentErrorf("empty team name")
	}

	if err = organization.IsUsableTeamName(t.Name); err != nil {
		return err
	}

	has, err := db.ExistByID[user_model.User](ctx, t.OrgID)
	if err != nil {
		return err
	}
	if !has {
		return organization.ErrOrgNotExist{ID: t.OrgID}
	}

	t.LowerName = strings.ToLower(t.Name)
	has, err = db.Exist[organization.Team](ctx, builder.Eq{
		"org_id":     t.OrgID,
		"lower_name": t.LowerName,
	})
	if err != nil {
		return err
	}
	if has {
		return organization.ErrTeamAlreadyExist{OrgID: t.OrgID, Name: t.LowerName}
	}

	return db.WithTx(ctx, func(ctx context.Context) error {
		if err = db.Insert(ctx, t); err != nil {
			return err
		}

		// insert units for team
		if len(t.Units) > 0 {
			for _, unit := range t.Units {
				unit.TeamID = t.ID
			}
			if err = db.Insert(ctx, &t.Units); err != nil {
				return err
			}
		}

		// Add all repositories to the team if it has access to all of them.
		if t.IncludesAllRepositories {
			err = repo_service.AddAllRepositoriesToTeam(ctx, t)
			if err != nil {
				return fmt.Errorf("addAllRepositories: %w", err)
			}
		}

		// Update organization number of teams.
		_, err = db.Exec(ctx, "UPDATE `user` SET num_teams=num_teams+1 WHERE id = ?", t.OrgID)
		return err
	})
}

// UpdateTeam updates information of team.
func UpdateTeam(ctx context.Context, t *organization.Team, authChanged, includeAllChanged bool) (err error) {
	if len(t.Name) == 0 {
		return util.NewInvalidArgumentErrorf("empty team name")
	}

	if len(t.Description) > 255 {
		t.Description = t.Description[:255]
	}

	return db.WithTx(ctx, func(ctx context.Context) error {
		t.LowerName = strings.ToLower(t.Name)
		has, err := db.Exist[organization.Team](ctx, builder.Eq{
			"org_id":     t.OrgID,
			"lower_name": t.LowerName,
		}.And(builder.Neq{"id": t.ID}),
		)
		if err != nil {
			return err
		} else if has {
			return organization.ErrTeamAlreadyExist{OrgID: t.OrgID, Name: t.LowerName}
		}

		sess := db.GetEngine(ctx)
		if _, err = sess.ID(t.ID).Cols("name", "lower_name", "description",
			"can_create_org_repo", "authorize", "includes_all_repositories").Update(t); err != nil {
			return fmt.Errorf("update: %w", err)
		}

		// update units for team
		if len(t.Units) > 0 {
			for _, unit := range t.Units {
				unit.TeamID = t.ID
			}
			// Delete team-unit.
			if _, err := sess.
				Where("team_id=?", t.ID).
				Delete(new(organization.TeamUnit)); err != nil {
				return err
			}
			if _, err = sess.Cols("org_id", "team_id", "type", "access_mode").Insert(&t.Units); err != nil {
				return err
			}
		}

		// Update access for team members if needed.
		if authChanged {
			repos, err := repo_model.GetTeamRepositories(ctx, &repo_model.SearchTeamRepoOptions{
				TeamID: t.ID,
			})
			if err != nil {
				return fmt.Errorf("GetTeamRepositories: %w", err)
			}

			for _, repo := range repos {
				if err = access_model.RecalculateTeamAccesses(ctx, repo, 0); err != nil {
					return fmt.Errorf("recalculateTeamAccesses: %w", err)
				}
			}
		}

		// Add all repositories to the team if it has access to all of them.
		if includeAllChanged && t.IncludesAllRepositories {
			err = repo_service.AddAllRepositoriesToTeam(ctx, t)
			if err != nil {
				return fmt.Errorf("addAllRepositories: %w", err)
			}
		}

		return nil
	})
}

// DeleteTeam deletes given team.
// It's caller's responsibility to assign organization ID.
func DeleteTeam(ctx context.Context, t *organization.Team) error {
	return db.WithTx(ctx, func(ctx context.Context) error {
		if err := t.LoadMembers(ctx); err != nil {
			return err
		}

		// update branch protections
		{
			protections := make([]*git_model.ProtectedBranch, 0, 10)
			err := db.GetEngine(ctx).In("repo_id",
				builder.Select("id").From("repository").Where(builder.Eq{"owner_id": t.OrgID})).
				Find(&protections)
			if err != nil {
				return fmt.Errorf("findProtectedBranches: %w", err)
			}
			for _, p := range protections {
				if err := git_model.RemoveTeamIDFromProtectedBranch(ctx, p, t.ID); err != nil {
					return err
				}
			}
		}

		if err := repo_service.RemoveAllRepositoriesFromTeam(ctx, t); err != nil {
			return err
		}

		if err := db.DeleteBeans(ctx,
			&organization.Team{ID: t.ID},
			&organization.TeamUser{OrgID: t.OrgID, TeamID: t.ID},
			&organization.TeamUnit{TeamID: t.ID},
			&organization.TeamInvite{TeamID: t.ID},
			&issues_model.Review{Type: issues_model.ReviewTypeRequest, ReviewerTeamID: t.ID}, // batch delete the binding relationship between team and PR (request review from team)
		); err != nil {
			return err
		}

		for _, tm := range t.Members {
			if err := removeInvalidOrgUser(ctx, t.OrgID, tm); err != nil {
				return err
			}
		}

		// Update organization number of teams.
		_, err := db.Exec(ctx, "UPDATE `user` SET num_teams=num_teams-1 WHERE id=?", t.OrgID)
		return err
	})
}

// AddTeamMember adds new membership of given team to given organization,
// the user will have membership to given organization automatically when needed.
func AddTeamMember(ctx context.Context, team *organization.Team, user *user_model.User) error {
	if user_model.IsUserBlockedBy(ctx, user, team.OrgID) {
		return user_model.ErrBlockedUser
	}

	isAlreadyMember, err := organization.IsTeamMember(ctx, team.OrgID, team.ID, user.ID)
	if err != nil || isAlreadyMember {
		return err
	}

	if err := organization.AddOrgUser(ctx, team.OrgID, user.ID); err != nil {
		return err
	}

	err = db.WithTx(ctx, func(ctx context.Context) error {
		// check in transaction
		isAlreadyMember, err = organization.IsTeamMember(ctx, team.OrgID, team.ID, user.ID)
		if err != nil || isAlreadyMember {
			return err
		}

		sess := db.GetEngine(ctx)

		if err := db.Insert(ctx, &organization.TeamUser{
			UID:    user.ID,
			OrgID:  team.OrgID,
			TeamID: team.ID,
		}); err != nil {
			return err
		} else if _, err := sess.Incr("num_members").ID(team.ID).Update(new(organization.Team)); err != nil {
			return err
		}

		team.NumMembers++
		return nil
	})
	if err != nil {
		return err
	}

	// this behaviour may spend much time so run it in a goroutine
	// FIXME: Update watch repos batchly
	if setting.Service.AutoWatchNewRepos {
		// Get team and its repositories.
		repos, err := repo_model.GetTeamRepositories(ctx, &repo_model.SearchTeamRepoOptions{
			TeamID: team.ID,
		})
		if err != nil {
			log.Error("GetTeamRepositories failed: %v", err)
		}

		go func(repos []*repo_model.Repository) {
			for _, repo := range repos {
				if err = repo_model.WatchRepo(graceful.GetManager().ShutdownContext(), user, repo, true); err != nil {
					log.Error("watch repo failed: %v", err)
				}
			}
		}(repos)
	}

	return nil
}

func removeTeamMember(ctx context.Context, team *organization.Team, user *user_model.User) error {
	e := db.GetEngine(ctx)
	isMember, err := organization.IsTeamMember(ctx, team.OrgID, team.ID, user.ID)
	if err != nil || !isMember {
		return err
	}

	// Check if the user to delete is the last member in owner team.
	if team.IsOwnerTeam() && team.NumMembers == 1 {
		return organization.ErrLastOrgOwner{UID: user.ID}
	}

	team.NumMembers--

	repos, err := repo_model.GetTeamRepositories(ctx, &repo_model.SearchTeamRepoOptions{
		TeamID: team.ID,
	})
	if err != nil {
		return err
	}

	if _, err := e.Delete(&organization.TeamUser{
		UID:    user.ID,
		OrgID:  team.OrgID,
		TeamID: team.ID,
	}); err != nil {
		return err
	} else if _, err = e.
		ID(team.ID).
		Cols("num_members").
		Update(team); err != nil {
		return err
	}

	// Delete access to team repositories.
	for _, repo := range repos {
		if err := access_model.RecalculateUserAccess(ctx, repo, user.ID); err != nil {
			return err
		}

		// Remove watches from now unaccessible
		if err := repo_service.ReconsiderWatches(ctx, repo, user); err != nil {
			return err
		}

		// Remove issue assignments from now unaccessible
		if err := repo_service.ReconsiderRepoIssuesAssignee(ctx, repo, user); err != nil {
			return err
		}
	}

	return removeInvalidOrgUser(ctx, team.OrgID, user)
}

func removeInvalidOrgUser(ctx context.Context, orgID int64, user *user_model.User) error {
	// Check if the user is a member of any team in the organization.
	if count, err := db.GetEngine(ctx).Count(&organization.TeamUser{
		UID:   user.ID,
		OrgID: orgID,
	}); err != nil {
		return err
	} else if count == 0 {
		org, err := organization.GetOrgByID(ctx, orgID)
		if err != nil {
			return err
		}

		return RemoveOrgUser(ctx, org, user)
	}
	return nil
}

// RemoveTeamMember removes member from given team of given organization.
func RemoveTeamMember(ctx context.Context, team *organization.Team, user *user_model.User) error {
	return db.WithTx(ctx, func(ctx context.Context) error {
		return removeTeamMember(ctx, team, user)
	})
}
