package binlog

import (
	"errors"
	"strings"
	"time"
)

var (
	ErrInvalidBinlogHeader = errors.New("invalid binlog file header")
	ErrEventTooSmall       = errors.New("event size too small")
)

const (
	CompressionNone uint64 = 255
	CompressionZSTD uint64 = 0
)

const (
	maxPooledRawDataCap = 4 << 20 // 4MB
	defaultReadBufSize  = 1 << 20 // 1MB
)

type TxDetail struct {
	StartPos           int             `json:"startPos"`
	EndPos             int             `json:"endPos"`
	RowCount           int             `json:"rowCount"`
	Timestamp          int64           `json:"timestamp"`
	Time               time.Time       `json:"time"`
	Sql                string          `json:"sql"`
	Db                 string          `json:"db"`
	Table              string          `json:"table"`
	SqlType            string          `json:"sqlType"`
	CompressionType    string          `json:"compressionType"`
	Rows               [][]interface{} `json:"rows"`
	ColumnTypes        []int           `json:"columnTypes,omitempty"`
	ColumnCollationIDs []uint64        `json:"columnCollationIds,omitempty"`
}

const (
	STATUS_PREPARE uint8 = iota
	STATUS_BEGIN
	STATUS_COMMIT
	STATUS_ROLLBACK
)

type Transaction struct {
	GTID          string     `json:"gtid"`
	Timestamp     int64      `json:"timestamp"`
	Time          time.Time  `json:"time"`
	StartPos      int        `json:"startPos"`
	EndPos        int        `json:"endPos"`
	Size          int        `json:"size"`
	RowsCount     int        `json:"rowsCount"`
	Status        uint8      `json:"status"`
	TxStartTime   int64      `json:"txStartTime"`
	TxEndTime     int64      `json:"txEndTime"`
	sqlOrigin     []string   `json:"sqlOrigin"`
	Txs           []TxDetail `json:"txs"`
	dmlEventCount int
}

func (t Transaction) GetSqlOrigin() []string {
	return t.sqlOrigin
}

type BinlogFilter struct {
	IncludeGtid      string
	ExcludeGtid      string
	IncludeTables    []string
	ExcludeTables    []string
	StartPos         int
	EndPos           int
	StartDate        time.Time
	EndDate          time.Time
	BigThan          int
	SmallThan        int
	OnlyShowGtid     bool
	OnlyShowDML      bool
	PickTxAllIfMatch bool
	ExcludeBlank     bool
	IncludeBlank     bool
}

type BinlogEvent struct {
	Type               string
	DB                 string
	TB                 string
	Data               string
	RowCnt             uint32
	Rows               [][]interface{}
	ColumnTypes        []int
	ColumnCollationIDs []uint64
	CompressionType    string
}

type tableMatcher struct {
	exactMatch map[string]bool
	dbWildcard map[string]bool
	tbWildcard map[string]bool
	matchAll   bool
}

func (m *tableMatcher) match(db, tb string) bool {
	db = strings.ToLower(strings.TrimSpace(db))
	tb = strings.ToLower(strings.TrimSpace(tb))

	if m.matchAll {
		return true
	}
	if m.dbWildcard[db] || m.tbWildcard[tb] {
		return true
	}
	if len(m.exactMatch) > 0 {
		// Go 1.12+ 对 map[string] 查找时 string([]byte) 不分配
		var buf [128]byte
		key := buf[:0]
		key = append(key, db...)
		key = append(key, '.')
		key = append(key, tb...)
		if m.exactMatch[string(key)] {
			return true
		}
	}
	return false
}