package service

import (
	"context"
	"strconv"

	"git.itzana.me/strafesnet/maps-service/pkg/api"
	"git.itzana.me/strafesnet/maps-service/pkg/datastore"
	"git.itzana.me/strafesnet/maps-service/pkg/model"
)

// CreateScriptPolicy implements createScriptPolicy operation.
//
// Create a new script policy.
//
// POST /script-policy
func (svc *Service) CreateScriptPolicy(ctx context.Context, req *api.ScriptPolicyCreate) (*api.ID, error) {
	userInfo, ok := ctx.Value("UserInfo").(UserInfo)
	if !ok {
		return nil, ErrUserInfo
	}

	if !userInfo.Roles.ScriptWrite {
		return nil, ErrPermissionDenied
	}

	from_script, err := svc.DB.Scripts().Get(ctx, req.FromScriptID)
	if err != nil {
		return nil, err
	}

	// the existence of ToScriptID does not need to be validated because it's checked by a foreign key constraint.

	script, err := svc.DB.ScriptPolicy().Create(ctx, model.ScriptPolicy{
		ID:             0,
		FromScriptHash: from_script.Hash,
		ToScriptID:     req.ToScriptID,
		Policy:         model.Policy(req.Policy),
	})
	if err != nil {
		return nil, err
	}

	return &api.ID{
		ID: script.ID,
	}, nil
}


// ListScriptPolicy implements listScriptPolicy operation.
//
// Get list of script policies.
//
// GET /script-policy
func (svc *Service) ListScriptPolicy(ctx context.Context, request *api.ListScriptPolicyReq) ([]api.ScriptPolicy, error) {
	filter := datastore.Optional()

	if request.Filter.IsSet() {
		f := request.Filter.Value
		if f.FromScriptHash.IsSet(){
			filter.AddNotNil("from_script_hash", f.FromScriptHash.Value)
		}
		if f.ToScriptID.IsSet(){
			filter.AddNotNil("to_script_id", f.ToScriptID.Value)
		}
		if f.Policy.IsSet(){
			filter.AddNotNil("policy", f.Policy.Value)
		}
	}

	items, err := svc.DB.ScriptPolicy().List(ctx, filter, model.Page{
		Number: request.Page.Number,
		Size:   request.Page.Size,
	})
	if err != nil {
		return nil, err
	}

	var resp []api.ScriptPolicy
	for i := 0; i < len(items); i++ {
		resp = append(resp, api.ScriptPolicy{
			ID:             items[i].ID,
			FromScriptHash: model.HashFormat(items[i].FromScriptHash),
			ToScriptID:     items[i].ToScriptID,
			Policy:         int32(items[i].Policy),
		})
	}

	return resp, nil
}

// DeleteScriptPolicy implements deleteScriptPolicy operation.
//
// Delete the specified script policy by ID.
//
// DELETE /script-policy/id/{ScriptPolicyID}
func (svc *Service) DeleteScriptPolicy(ctx context.Context, params api.DeleteScriptPolicyParams) error {
	userInfo, ok := ctx.Value("UserInfo").(UserInfo)
	if !ok {
		return ErrUserInfo
	}

	if !userInfo.Roles.ScriptWrite {
		return ErrPermissionDenied
	}

	return svc.DB.ScriptPolicy().Delete(ctx, params.ScriptPolicyID)
}

// GetScriptPolicy implements getScriptPolicy operation.
//
// Get the specified script policy by ID.
//
// GET /script-policy/id/{ScriptPolicyID}
func (svc *Service) GetScriptPolicy(ctx context.Context, params api.GetScriptPolicyParams) (*api.ScriptPolicy, error) {
	_, ok := ctx.Value("UserInfo").(UserInfo)
	if !ok {
		return nil, ErrUserInfo
	}

	// Read permission for script policy only requires you to be logged in

	policy, err := svc.DB.ScriptPolicy().Get(ctx, params.ScriptPolicyID)
	if err != nil {
		return nil, err
	}

	return &api.ScriptPolicy{
		ID:             policy.ID,
		FromScriptHash: model.HashFormat(policy.FromScriptHash),
		ToScriptID:     policy.ToScriptID,
		Policy:         int32(policy.Policy),
	}, nil
}

// GetScriptPolicyFromHash implements getScriptPolicyFromHash operation.
//
// Get the policy for the given hash of script source code.
//
// GET /script-policy/hash/{FromScriptHash}
func (svc *Service) GetScriptPolicyFromHash(ctx context.Context, params api.GetScriptPolicyFromHashParams) (*api.ScriptPolicy, error) {
	_, ok := ctx.Value("UserInfo").(UserInfo)
	if !ok {
		return nil, ErrUserInfo
	}

	// Read permission for script policy only requires you to be logged in

	// parse hash from hex
	hash, err := strconv.ParseUint(params.FromScriptHash, 16, 64)
	if err != nil {
		return nil, err
	}

	policy, err := svc.DB.ScriptPolicy().GetFromHash(ctx, hash)
	if err != nil {
		return nil, err
	}

	return &api.ScriptPolicy{
		ID:             policy.ID,
		FromScriptHash: model.HashFormat(policy.FromScriptHash),
		ToScriptID:     policy.ToScriptID,
		Policy:         int32(policy.Policy),
	}, nil
}

// UpdateScriptPolicy implements updateScriptPolicy operation.
//
// Update the specified script policy by ID.
//
// PATCH /script-policy/id/{ScriptPolicyID}
func (svc *Service) UpdateScriptPolicy(ctx context.Context, req *api.ScriptPolicyUpdate, params api.UpdateScriptPolicyParams) error {
	userInfo, ok := ctx.Value("UserInfo").(UserInfo)
	if !ok {
		return ErrUserInfo
	}

	if !userInfo.Roles.ScriptWrite {
		return ErrPermissionDenied
	}

	pmap := datastore.Optional()
	if from_script_id, ok := req.FromScriptID.Get(); ok {
		from_script, err := svc.DB.Scripts().Get(ctx, from_script_id)
		if err != nil {
			return err
		}
		pmap.Add("from_script_hash", from_script.Hash)
	}
	if to_script_id, ok := req.ToScriptID.Get(); ok {
		pmap.Add("to_script_id", to_script_id)
	}
	if policy, ok := req.Policy.Get(); ok {
		pmap.Add("policy", policy)
	}
	return svc.DB.ScriptPolicy().Update(ctx, req.ID, pmap)
}