package state

import (
	"fmt"
	"time"

	"xorm.io/xorm"
	"xorm.io/xorm/names"
)

type BaseModel struct {
	ID        int64     `xorm:"pk autoincr" json:"id"`
	CreatedAt time.Time `xorm:"created" json:"created_at"`
	UpdatedAt time.Time `xorm:"updated" json:"updated_at"`
	// DeletedAt *time.Time `xorm:"deleted" json:"deleted_at,omitempty"`
}

type Namespace struct {
	BaseModel    `xorm:"extends"`
	Name         string `xorm:"varchar(255) unique notnull" json:"name"`
	PasswordHash string `xorm:"varchar(255)" json:"-"`
}

type Repo struct {
	BaseModel   `xorm:"extends"`
	NamespaceID int64  `xorm:"notnull unique(cred)" json:"namespace_id"`
	Name        string `xorm:"varchar(255) notnull unique(cred)" json:"reponame"`
	IsPrivate   bool   `xorm:"default false" json:"is_private"`
}

type SSHKey struct {
	BaseModel   `xorm:"extends"`
	PublicKey   string     `xorm:"text notnull" json:"-"`
	Fingerprint string     `xorm:"varchar(255) unique notnull" json:"fingerprint"`
	KeyType     string     `xorm:"varchar(50) notnull" json:"key_type"`
	Comment     string     `xorm:"varchar(255)" json:"comment,omitempty"`
	LastUsedAt  *time.Time `xorm:"" json:"last_used_at,omitempty"`
}

type PAT struct {
	BaseModel  `xorm:"extends"`
	TokenHash  string     `xorm:"varchar(64) unique notnull" json:"-"`
	Prefix     string     `xorm:"varchar(20)" json:"prefix"`
	Name       string     `xorm:"varchar(255)" json:"name"`
	ExpiresAt  *time.Time `xorm:"" json:"expires_at,omitempty"`
	LastUsedAt *time.Time `xorm:"" json:"last_used_at,omitempty"`
}

type ACL struct {
	BaseModel  `xorm:"extends"`
	CredType   int    `xorm:"notnull unique(cred) index" json:"cred_type"`
	CredID     int64  `xorm:"notnull unique(cred)" json:"cred_id"`
	TargetType int    `xorm:"notnull unique(cred) index" json:"target_type"`
	TargetID   int64  `xorm:"notnull unique(cred)" json:"target_id"`
	Perm       string `xorm:"varchar(20) default 'read'" json:"perm"`
}

type CredType int

const (
	CredTypePAT      CredType = 0
	CredTypeSSH      CredType = 1
	CredTypeUserPswd CredType = 2
)

type TargetType int

const (
	TargetTypeRepo TargetType = 0
	TargetTypeNS   TargetType = 1
)

func InitEngine(driverName, dataSourceName string) (*xorm.Engine, error) {
	engine, err := xorm.NewEngine(driverName, dataSourceName)
	if err != nil {
		return nil, err
	}
	engine.SetTableMapper(names.GonicMapper{})
	engine.SetColumnMapper(names.GonicMapper{})
	if driverName == sqliteDriver {
		if err := migrateLegacySQLite(engine); err != nil {
			_ = engine.Close()
			return nil, err
		}
	}
	if err := engine.Sync2(
		new(Namespace),
		new(Repo),
		new(SSHKey),
		new(PAT),
		new(ACL),
	); err != nil {
		return nil, err
	}
	return engine, nil
}

// migrateLegacySQLite handles model field renames that Sync2 otherwise treats
// as new NOT NULL columns. The migration is idempotent and preserves old repos.
func migrateLegacySQLite(engine *xorm.Engine) error {
	rows, err := engine.QueryString("PRAGMA table_info(repo)")
	if err != nil {
		return fmt.Errorf("inspect legacy repo schema: %w", err)
	}
	columns := make(map[string]bool, len(rows))
	for _, row := range rows {
		columns[row["name"]] = true
	}
	if columns["repo_name"] && !columns["name"] {
		if _, err := engine.Exec("ALTER TABLE repo RENAME COLUMN repo_name TO name"); err != nil {
			return fmt.Errorf("migrate repo column repo_name to name: %w", err)
		}
	}
	return nil
}