// Copyright 2023 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package devcontainer

import (
	"context"
	"strings"

	"code.gitea.io/gitea/models/db"
	"code.gitea.io/gitea/modules/log"
	"code.gitea.io/gitea/modules/timeutil"
	"code.gitea.io/gitea/modules/util"

	"xorm.io/builder"
)

// DevcontainerVariable represents a variable that can be used in actions
//
// It can be:
//  1. global variable, OwnerID is 0 and RepoID is 0
//  2. org/user level variable, OwnerID is org/user ID and RepoID is 0
//  3. repo level variable, OwnerID is 0 and RepoID is repo ID
//
// Please note that it's not acceptable to have both OwnerID and RepoID to be non-zero,
// or it will be complicated to find variables belonging to a specific owner.
// For example, conditions like `OwnerID = 1` will also return variable {OwnerID: 1, RepoID: 1},
// but it's a repo level variable, not an org/user level variable.
// To avoid this, make it clear with {OwnerID: 0, RepoID: 1} for repo level variables.
type DevcontainerVariable struct {
	ID          int64              `xorm:"pk autoincr"`
	OwnerID     int64              `xorm:"UNIQUE(owner_repo_name)"`
	RepoID      int64              `xorm:"INDEX UNIQUE(owner_repo_name)"`
	Name        string             `xorm:"UNIQUE(owner_repo_name) NOT NULL"`
	Data        string             `xorm:"LONGTEXT NOT NULL"`
	Description string             `xorm:"TEXT"`
	CreatedUnix timeutil.TimeStamp `xorm:"created NOT NULL"`
	UpdatedUnix timeutil.TimeStamp `xorm:"updated"`
}

const (
	VariableDescriptionMaxLength = 4096
)

func init() {
	db.RegisterModel(new(DevcontainerVariable))
}

func InsertVariable(ctx context.Context, ownerID, repoID int64, name, data, description string) (*DevcontainerVariable, error) {
	if ownerID != 0 && repoID != 0 {
		// It's trying to create a variable that belongs to a repository, but OwnerID has been set accidentally.
		// Remove OwnerID to avoid confusion; it's not worth returning an error here.
		ownerID = 0
	}

	description = util.TruncateRunes(description, VariableDescriptionMaxLength)

	variable := &DevcontainerVariable{
		OwnerID:     ownerID,
		RepoID:      repoID,
		Name:        strings.ToUpper(name),
		Data:        data,
		Description: description,
	}
	return variable, db.Insert(ctx, variable)
}

type FindVariablesOpts struct {
	db.ListOptions
	IDs     []int64
	RepoID  int64
	OwnerID int64 // it will be ignored if RepoID is set
	Name    string
}

func (opts FindVariablesOpts) ToConds() builder.Cond {
	cond := builder.NewCond()

	if len(opts.IDs) > 0 {
		if len(opts.IDs) == 1 {
			cond = cond.And(builder.Eq{"id": opts.IDs[0]})
		} else {
			cond = cond.And(builder.In("id", opts.IDs))
		}
	}

	// Since we now support instance-level variables,
	// there is no need to check for null values for `owner_id` and `repo_id`
	cond = cond.And(builder.Eq{"repo_id": opts.RepoID})
	if opts.RepoID != 0 { // if RepoID is set
		// ignore OwnerID and treat it as 0
		cond = cond.And(builder.Eq{"owner_id": 0})
	} else {
		cond = cond.And(builder.Eq{"owner_id": opts.OwnerID})
	}

	if opts.Name != "" {
		cond = cond.And(builder.Eq{"name": strings.ToUpper(opts.Name)})
	}
	return cond
}

func FindVariables(ctx context.Context, opts FindVariablesOpts) ([]*DevcontainerVariable, error) {
	return db.Find[DevcontainerVariable](ctx, opts)
}

func UpdateVariableCols(ctx context.Context, variable *DevcontainerVariable, cols ...string) (bool, error) {

	variable.Description = util.TruncateRunes(variable.Description, VariableDescriptionMaxLength)

	variable.Name = strings.ToUpper(variable.Name)
	count, err := db.GetEngine(ctx).
		ID(variable.ID).
		Cols(cols...).
		Update(variable)
	return count != 0, err
}

func DeleteVariable(ctx context.Context, id int64) error {
	if _, err := db.DeleteByID[DevcontainerVariable](ctx, id); err != nil {
		return err
	}
	return nil
}

func GetVariables(ctx context.Context, userId, repoID int64) (map[string]string, error) {
	variables := map[string]string{}

	// Global
	globalVariables, err := db.Find[DevcontainerVariable](ctx, FindVariablesOpts{})
	if err != nil {
		log.Error("find global variables: %v", err)
		return nil, err
	}

	// Org / User level
	ownerVariables, err := db.Find[DevcontainerVariable](ctx, FindVariablesOpts{OwnerID: userId})
	if err != nil {
		log.Error("find variables of org: %d, error: %v", userId, err)
		return nil, err
	}

	// Repo level
	repoVariables, err := db.Find[DevcontainerVariable](ctx, FindVariablesOpts{RepoID: repoID})
	if err != nil {
		log.Error("find variables of repo: %d, error: %v", repoID, err)
		return nil, err
	}

	// Level precedence: Org / User > Repo > Global
	for _, v := range append(globalVariables, append(repoVariables, ownerVariables...)...) {
		variables[v.Name] = v.Data
	}

	return variables, nil
}