// Copyright (c) 2015-present Mattermost, Inc. All Rights Reserved.
// See LICENSE.txt for license information.

package app

import (
	"errors"
	"net/http"
	"strings"

	"github.com/mattermost/mattermost/server/public/model"
	"github.com/mattermost/mattermost/server/public/shared/mlog"
	"github.com/mattermost/mattermost/server/public/shared/request"
	"github.com/mattermost/mattermost/server/v8/channels/store"
)

// getChannelIDFromJobData extracts channel ID from access control sync job data.
// Returns channel ID if the job is for a specific channel, empty string if it's a system-wide job.
func (a *App) getChannelIDFromJobData(jobData model.StringMap) string {
	policyID, ok := jobData["policy_id"]
	if !ok || policyID == "" {
		return ""
	}

	// In the access control system:
	// - Channel policies have ID == channelID
	// - Parent policies have their own system-wide ID
	//
	// For channel admin jobs: policy_id is channelID (since channel policy ID equals channel ID)
	// For system admin jobs: policy_id could be either channel policy ID or parent policy ID
	//
	// We return the parent_id as channelID because:
	// 1. If it's a channel policy ID, it equals the channel ID
	// 2. If it's a parent policy ID, the permission check will fail safely
	// 3. This maintains security: only users with permission to that specific ID can create the job
	return policyID
}

func (a *App) GetJob(rctx request.CTX, id string) (*model.Job, *model.AppError) {
	job, err := a.Srv().Store().Job().Get(rctx, id)
	if err != nil {
		var nfErr *store.ErrNotFound
		switch {
		case errors.As(err, &nfErr):
			return nil, model.NewAppError("GetJob", "app.job.get.app_error", nil, "", http.StatusNotFound).Wrap(err)
		default:
			return nil, model.NewAppError("GetJob", "app.job.get.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
		}
	}

	return job, nil
}

func (a *App) GetJobsByTypePage(rctx request.CTX, jobType string, page int, perPage int) ([]*model.Job, *model.AppError) {
	jobs, err := a.Srv().Store().Job().GetAllByTypePage(rctx, jobType, page, perPage)
	if err != nil {
		return nil, model.NewAppError("GetJobsByType", "app.job.get_all.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
	}
	return jobs, nil
}

func (a *App) GetJobsByTypesPage(rctx request.CTX, jobType []string, page int, perPage int) ([]*model.Job, *model.AppError) {
	jobs, err := a.Srv().Store().Job().GetAllByTypesPage(rctx, jobType, page, perPage)
	if err != nil {
		return nil, model.NewAppError("GetJobsByType", "app.job.get_all.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
	}
	return jobs, nil
}

func (a *App) GetJobsByTypeAndData(rctx request.CTX, jobType string, data map[string]string) ([]*model.Job, *model.AppError) {
	jobs, err := a.Srv().Store().Job().GetByTypeAndData(rctx, jobType, data, false)
	if err != nil {
		return nil, model.NewAppError("GetJobsByTypeAndData", "app.job.get_all.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
	}
	return jobs, nil
}

func (a *App) GetJobsByTypesAndStatuses(rctx request.CTX, jobTypes []string, status []string, page int, perPage int) ([]*model.Job, *model.AppError) {
	jobs, err := a.Srv().Store().Job().GetAllByTypesAndStatusesPage(rctx, jobTypes, status, page*perPage, perPage)
	if err != nil {
		return nil, model.NewAppError("GetAllByTypesAndStatusesPage", "app.job.get_all.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
	}
	return jobs, nil
}

func (a *App) CreateJob(rctx request.CTX, job *model.Job) (*model.Job, *model.AppError) {
	switch job.Type {
	case model.JobTypeAccessControlSync:
		// Route ABAC jobs to specialized deduplication handler
		return a.CreateAccessControlSyncJob(rctx, job.Data)
	case model.JobTypeAccessControlTeamSync:
		// Route team ABAC jobs to specialized deduplication handler
		return a.CreateAccessControlTeamSyncJob(rctx, job.Data)
	default:
		return a.Srv().Jobs.CreateJob(rctx, job.Type, job.Data)
	}
}

func (a *App) CreateAccessControlSyncJob(rctx request.CTX, jobData map[string]string) (*model.Job, *model.AppError) {
	policyID := jobData["policy_id"]
	teamID := jobData["team_id"]
	requesterID := jobData["requester_id"]
	isAdmin := jobData["requester_is_admin"] == "true"

	// Remove transient fields before persisting.
	delete(jobData, "requester_id")
	delete(jobData, "requester_is_admin")

	if policyID != "" {
		a.cancelExistingAccessControlSyncJobs(rctx, model.JobTypeAccessControlSync, map[string]string{"policy_id": policyID}, "policy_id", policyID)
	}

	if teamID != "" && policyID == "" {
		a.cancelExistingAccessControlSyncJobs(rctx, model.JobTypeAccessControlSync, map[string]string{"team_id": teamID}, "team_id", teamID)
	}

	// For team-scoped syncs by non-admins, resolve which channels the
	// requester can sync based on self-inclusion (attribute match).
	if teamID != "" && policyID == "" && requesterID != "" && !isAdmin {
		channelIDs, appErr := a.resolveTeamSyncChannelIDs(rctx, teamID, requesterID)
		if appErr != nil {
			return nil, appErr
		}
		if len(channelIDs) > 0 {
			jobData["channel_ids"] = strings.Join(channelIDs, ",")
		}
	}

	return a.Srv().Jobs.CreateJob(rctx, model.JobTypeAccessControlSync, jobData)
}

// CreateAccessControlTeamSyncJob creates a team membership sync job, first
// canceling any pending/in-progress sync for the same policy so two never run
// concurrently. A team-type policy's ID equals its team ID, so deduplicating on
// policy_id deduplicates per team. Without this, overlapping syncs on separate
// HA nodes emit duplicate removal/addition DMs and audit records for one change.
func (a *App) CreateAccessControlTeamSyncJob(rctx request.CTX, jobData map[string]string) (*model.Job, *model.AppError) {
	policyID := jobData["policy_id"]

	// Strip transient fields before persisting. Only channel syncs inject these,
	// so this is defensive against a hand-crafted request body.
	delete(jobData, "requester_id")
	delete(jobData, "requester_is_admin")

	if policyID != "" {
		a.cancelExistingAccessControlSyncJobs(rctx, model.JobTypeAccessControlTeamSync, map[string]string{"policy_id": policyID}, "policy_id", policyID)
	}

	return a.Srv().Jobs.CreateJob(rctx, model.JobTypeAccessControlTeamSync, jobData)
}

// cancelExistingAccessControlSyncJobs cancels pending/in-progress sync jobs of
// the given type matching the data filter, for deduplication.
func (a *App) cancelExistingAccessControlSyncJobs(rctx request.CTX, jobType string, dataFilter map[string]string, logKey, logValue string) {
	existingJobs, err := a.Srv().Store().Job().GetByTypeAndData(rctx, jobType, dataFilter, true, model.JobStatusPending, model.JobStatusInProgress)
	if err != nil {
		rctx.Logger().Warn("Failed to query existing sync jobs for deduplication", mlog.Err(err))
		return
	}

	for _, job := range existingJobs {
		rctx.Logger().Info("Canceling existing access control sync job before creating new one",
			mlog.String("job_id", job.Id),
			mlog.String(logKey, logValue),
			mlog.String("status", job.Status))
		if err := a.Srv().Jobs.SetJobCanceled(job); err != nil {
			rctx.Logger().Warn("Failed to cancel existing access control sync job",
				mlog.String("job_id", job.Id),
				mlog.String(logKey, logValue),
				mlog.Err(err))
		}
	}
}

// resolveTeamSyncChannelIDs returns channel IDs the requester can sync,
// filtered by self-inclusion (same logic as SearchTeamAccessPolicies).
func (a *App) resolveTeamSyncChannelIDs(rctx request.CTX, teamID, requesterID string) ([]string, *model.AppError) {
	policies, _, appErr := a.SearchTeamAccessPolicies(rctx, teamID, requesterID, model.AccessControlPolicySearch{
		Limit: teamPoliciesMaxFetch,
	})
	if appErr != nil {
		return nil, appErr
	}

	var channelIDs []string
	for _, policy := range policies {
		if policy.Props == nil {
			continue
		}
		childIDs, ok := policy.Props["child_ids"].([]string)
		if !ok {
			// Handle []any from JSON unmarshaling
			if rawIDs, ok2 := policy.Props["child_ids"].([]any); ok2 {
				for _, raw := range rawIDs {
					if id, ok3 := raw.(string); ok3 {
						channelIDs = append(channelIDs, id)
					}
				}
				continue
			}
			continue
		}
		channelIDs = append(channelIDs, childIDs...)
	}

	return channelIDs, nil
}

func (a *App) CancelJob(rctx request.CTX, jobId string) *model.AppError {
	return a.Srv().Jobs.RequestCancellation(rctx, jobId)
}

func (a *App) UpdateJobStatus(rctx request.CTX, job *model.Job, newStatus string) *model.AppError {
	switch newStatus {
	case model.JobStatusPending:
		return a.Srv().Jobs.SetJobPending(job)
	case model.JobStatusCancelRequested:
		return a.Srv().Jobs.RequestCancellation(rctx, job.Id)
	case model.JobStatusCanceled:
		return a.Srv().Jobs.SetJobCanceled(job)
	default:
		return model.NewAppError("UpdateJobStatus", "app.job.update_status.app_error", nil, "", http.StatusInternalServerError)
	}
}

func (a *App) SessionHasPermissionToCreateJob(session model.Session, job *model.Job) (bool, *model.Permission) {
	switch job.Type {
	case model.JobTypeDataRetention:
		return a.SessionHasPermissionTo(session, model.PermissionCreateDataRetentionJob), model.PermissionCreateDataRetentionJob
	case model.JobTypeMessageExport:
		return a.SessionHasPermissionTo(session, model.PermissionCreateComplianceExportJob), model.PermissionCreateComplianceExportJob
	case model.JobTypeElasticsearchPostIndexing:
		return a.SessionHasPermissionTo(session, model.PermissionCreateElasticsearchPostIndexingJob), model.PermissionCreateElasticsearchPostIndexingJob
	case model.JobTypeElasticsearchPostAggregation:
		return a.SessionHasPermissionTo(session, model.PermissionCreateElasticsearchPostAggregationJob), model.PermissionCreateElasticsearchPostAggregationJob
	case model.JobTypeLdapSync:
		return a.SessionHasPermissionTo(session, model.PermissionCreateLdapSyncJob), model.PermissionCreateLdapSyncJob
	case
		model.JobTypeMigrations,
		model.JobTypePlugins,
		model.JobTypeProductNotices,
		model.JobTypeExpiryNotify,
		model.JobTypeActiveUsers,
		model.JobTypeImportProcess,
		model.JobTypeImportDelete,
		model.JobTypeExportProcess,
		model.JobTypeExportDelete,
		model.JobTypeCloud,
		model.JobTypeExtractContent,
		model.JobTypeCleanupExpiredAccessTokens,
		model.JobTypeNotifyExpiringAccessTokens:
		return a.SessionHasPermissionTo(session, model.PermissionManageJobs), model.PermissionManageJobs
	case model.JobTypeAccessControlTeamSync:
		if a.SessionHasPermissionTo(session, model.PermissionManageSystem) {
			return true, model.PermissionManageSystem
		}
		// Team-type policies use the team ID as the policy ID.
		// Allow a team admin to trigger a sync job for their own team's policy.
		if policyID, ok := job.Data["policy_id"]; ok && policyID != "" && model.IsValidId(policyID) {
			if a.SessionHasPermissionToTeam(session, policyID, model.PermissionManageTeamAccessRules) {
				return true, model.PermissionManageTeamAccessRules
			}
		}
		return false, model.PermissionManageSystem
	case model.JobTypeAccessControlSync:
		// Allow system admins to create access control sync jobs
		hasSystemPermission := a.SessionHasPermissionTo(session, model.PermissionManageSystem)
		if hasSystemPermission {
			return true, model.PermissionManageSystem
		}

		// For channel admins, check if they have permission for the specific channel/policy
		channelID := a.getChannelIDFromJobData(job.Data)
		if channelID != "" {
			// Check specific channel permission
			ctx := request.EmptyContext(a.Srv().Log())
			hasChannelPermission, _ := a.HasPermissionToChannel(ctx, session.UserId, channelID, model.PermissionManageChannelAccessRules)
			if hasChannelPermission {
				return true, model.PermissionManageChannelAccessRules
			}
		}

		// Check team admin permission. This is needed for jobs that are scoped to a team but don't specify a channel (i.e. team-level syncs).
		teamID, hasTeamID := job.Data["team_id"]
		if hasTeamID && teamID != "" && model.IsValidId(teamID) && job.Data["policy_id"] == "" {
			if a.SessionHasPermissionToTeam(session, teamID, model.PermissionManageTeamAccessRules) {
				return true, model.PermissionManageTeamAccessRules
			}
		}

		// Check team admin permission for policy-scoped syncs (e.g. triggered after policy creation).
		// Verify the team admin owns the policy via ValidateTeamAdminPolicyOwnership.
		policyID, hasPolicyID := job.Data["policy_id"]
		if hasPolicyID && policyID != "" && model.IsValidId(policyID) && hasTeamID && teamID != "" && model.IsValidId(teamID) {
			if a.SessionHasPermissionToTeam(session, teamID, model.PermissionManageTeamAccessRules) {
				ctx := request.EmptyContext(a.Srv().Log())
				if owned, appErr := a.ValidateTeamAdminPolicyOwnership(ctx, teamID, policyID); appErr == nil && owned {
					return true, model.PermissionManageTeamAccessRules
				}
			}
		}

		return false, model.PermissionManageSystem
	}

	return false, nil
}

func (a *App) SessionHasPermissionToManageJob(session model.Session, job *model.Job) (bool, *model.Permission) {
	var permission *model.Permission

	switch job.Type {
	case model.JobTypeDataRetention:
		permission = model.PermissionManageDataRetentionJob
	case model.JobTypeMessageExport:
		permission = model.PermissionManageComplianceExportJob
	case model.JobTypeElasticsearchPostIndexing:
		permission = model.PermissionManageElasticsearchPostIndexingJob
	case model.JobTypeElasticsearchPostAggregation:
		permission = model.PermissionManageElasticsearchPostAggregationJob
	case model.JobTypeLdapSync:
		permission = model.PermissionManageLdapSyncJob
	case
		model.JobTypeMigrations,
		model.JobTypePlugins,
		model.JobTypeProductNotices,
		model.JobTypeExpiryNotify,
		model.JobTypeActiveUsers,
		model.JobTypeImportProcess,
		model.JobTypeImportDelete,
		model.JobTypeExportProcess,
		model.JobTypeExportDelete,
		model.JobTypeCloud,
		model.JobTypeExtractContent,
		model.JobTypeCleanupExpiredAccessTokens:
		permission = model.PermissionManageJobs
	case model.JobTypeAccessControlSync:
		permission = model.PermissionManageSystem
	case model.JobTypeAccessControlTeamSync:
		if a.SessionHasPermissionTo(session, model.PermissionManageSystem) {
			return true, model.PermissionManageSystem
		}
		if policyID, ok := job.Data["policy_id"]; ok && policyID != "" && model.IsValidId(policyID) {
			if a.SessionHasPermissionToTeam(session, policyID, model.PermissionManageTeamAccessRules) {
				return true, model.PermissionManageTeamAccessRules
			}
		}
		return false, model.PermissionManageSystem
	}

	if permission == nil {
		return false, nil
	}

	return a.SessionHasPermissionTo(session, permission), permission
}

func (a *App) SessionHasPermissionToReadJob(session model.Session, jobType string) (bool, *model.Permission) {
	var permission *model.Permission

	switch jobType {
	case model.JobTypeDataRetention:
		permission = model.PermissionReadDataRetentionJob
	case model.JobTypeMessageExport:
		permission = model.PermissionReadComplianceExportJob
	case model.JobTypeElasticsearchPostIndexing:
		permission = model.PermissionReadElasticsearchPostIndexingJob
	case model.JobTypeElasticsearchPostAggregation:
		permission = model.PermissionReadElasticsearchPostAggregationJob
	case model.JobTypeLdapSync:
		permission = model.PermissionReadLdapSyncJob
	case
		model.JobTypeMigrations,
		model.JobTypePlugins,
		model.JobTypeProductNotices,
		model.JobTypeExpiryNotify,
		model.JobTypeActiveUsers,
		model.JobTypeImportProcess,
		model.JobTypeImportDelete,
		model.JobTypeExportProcess,
		model.JobTypeExportDelete,
		model.JobTypeCloud,
		model.JobTypeMobileSessionMetadata,
		model.JobTypeExtractContent,
		model.JobTypePostPersistentNotifications,
		model.JobTypeDeleteExpiredPosts,
		model.JobTypeCleanupExpiredAccessTokens:
		permission = model.PermissionReadJobs
	case model.JobTypeAccessControlSync:
		permission = model.PermissionManageSystem
	case model.JobTypeAccessControlTeamSync:
		if a.SessionHasPermissionTo(session, model.PermissionManageSystem) {
			return true, model.PermissionManageSystem
		}
		permission = model.PermissionManageTeamAccessRules
	}

	if permission == nil {
		return false, nil
	}

	return a.SessionHasPermissionTo(session, permission), permission
}