package condition

import (
	"encoding/json"
	"fmt"
	"reflect"
	"strings"

	"git.fsdpf.net/go/db"
	"git.fsdpf.net/go/db/exp"
	"git.fsdpf.net/go/db/sqlgen"
	"git.fsdpf.net/go/reflux/valuex"
)

type TokenType string
type ConditionOperator = exp.BooleanOperation

const (
	SQL    TokenType = "sql"
	FUNC   TokenType = "func"
	PARAM  TokenType = "param"
	STRING TokenType = "string"
)

const (
	IS_NULL     ConditionOperator = exp.IsOp
	IS_NOT_NULL ConditionOperator = exp.IsNotOp
	EQ          ConditionOperator = exp.EqOp             // =
	NE          ConditionOperator = exp.NeqOp            // != or <>
	GT          ConditionOperator = exp.GtOp             // >
	GE          ConditionOperator = exp.GteOp            // >=
	LT          ConditionOperator = exp.LtOp             // <
	LE          ConditionOperator = exp.LteOp            // <=
	LIKE        ConditionOperator = exp.LikeOp           // LIKE
	NOT_LIKE    ConditionOperator = exp.NotLikeOp        // NOT LIKE
	IN          ConditionOperator = exp.InOp             // IN
	NOT_IN      ConditionOperator = exp.NotInOp          // NOT IN
	REGEXP      ConditionOperator = exp.RegexpILikeOp    // REGEXP
	NOT_REGEXP  ConditionOperator = exp.RegexpNotILikeOp // NOT REGEXP
)

type ExprOption func(option *ConditionExpr)

type ConditionExpr struct {
	parent            *Condition
	operator          ConditionOperator
	field             string
	fieldResource     string
	fieldSqlFunc      string
	fieldSqlFuncParam string
	ignoreEmptyParma  bool
	tokenType         TokenType
	token             string
	matchPrefix       string // 匹配前缀
}

func (this ConditionExpr) GetOperator() ConditionOperator {
	return this.operator
}

func (this *ConditionExpr) SetMatchPrefix(s string) *ConditionExpr {
	this.matchPrefix = s
	return this
}

func (this ConditionExpr) GetField() string {
	return this.field
}

func (this ConditionExpr) GetFieldResource() string {
	return this.fieldResource
}

func (this *ConditionExpr) AppendTo(c *Condition) {
	this.parent = c
}

func (this ConditionExpr) ToSql(m TokenValue) db.Expression {
	var first exp.Expression = db.T(this.fieldResource).Col(this.field)

	if strings.Contains(this.field, "->") {
		first = db.L("?."+this.field+"", db.T(this.fieldResource))
	}

	var value db.Expression = this.GetTokenSqlValue(m)

	switch this.GetOperator() {
	case LIKE, NOT_LIKE:
		value = exp.NewSQLFunctionExpression("CONCAT", "%", value, "%")
	}

	if this.fieldSqlFunc == "" {
		return exp.NewBooleanExpression(this.GetOperator(), first, value)
	}

	switch strings.ToLower(this.fieldSqlFunc) {
	case "json_member_of":
		if this.fieldSqlFuncParam != "" {
			return exp.NewSQLFunctionExpression("JSON_CONTAINS", db.L(this.fieldSqlFuncParam, value), exp.NewSQLFunctionExpression("JSON_ARRAY", first))
		}
		return exp.NewSQLFunctionExpression("JSON_CONTAINS", value, exp.NewSQLFunctionExpression("JSON_ARRAY", first))
	case "json_contains":
		if this.fieldSqlFuncParam != "" {
			return exp.NewSQLFunctionExpression("JSON_CONTAINS", db.L(this.fieldSqlFuncParam, first), exp.NewSQLFunctionExpression("JSON_ARRAY", value))
		}
		return exp.NewSQLFunctionExpression("JSON_CONTAINS", first, exp.NewSQLFunctionExpression("JSON_ARRAY", value))
	}

	if this.fieldSqlFuncParam == "" {
		first = exp.NewSQLFunctionExpression(this.fieldSqlFunc, first)
	} else {
		first = exp.NewSQLFunctionExpression(this.fieldSqlFunc, first, db.L(this.fieldSqlFuncParam))
	}

	return exp.NewBooleanExpression(this.GetOperator(), first, value)
}

func (this ConditionExpr) GetTokenName() string {
	return this.token
}

func (this ConditionExpr) GetTokenType() TokenType {
	return this.tokenType
}

func (this *ConditionExpr) GetTokenSqlValue(m TokenValue) exp.LiteralExpression {
	if this.GetTokenType() == SQL {
		return db.L(this.token)
	}

	if this.operator == IS_NULL || this.operator == IS_NOT_NULL {
		return db.V(nil)
	}

	v := this.GetTokenValue(m)
	rv := reflect.ValueOf(v)

	if rv.Kind() == reflect.Ptr {
		rv = reflect.Indirect(rv)
	}

	switch rv.Kind() {
	case reflect.Invalid:
		return db.V("")
	case reflect.Slice:
		// 强制使用 in
		if this.operator == EQ {
			this.operator = IN
		}
		return db.V(v)
	case reflect.String:
		if this.operator == IN || this.operator == NOT_IN {
			parts := strings.Split(rv.String(), ",")
			for i, p := range parts {
				parts[i] = strings.TrimSpace(p)
			}
			return db.V(parts)
		}
	case reflect.Struct:
		b, _ := json.Marshal(v)
		return db.V(b)
	}
	return db.V(v)
}

func (this ConditionExpr) GetTokenValue(m TokenValue) any {
	switch this.GetTokenType() {
	case PARAM:
		var result valuex.Accessor

		if this.matchPrefix != "" {
			result = m.GetParam(fmt.Sprintf("%s.%s", this.matchPrefix, this.token))
		} else {
			result = m.GetParam(this.token)
		}

		return result.Any()
	case STRING:
		return this.token
	case FUNC:
		switch this.token {
		case "UserID":
			return m.User().ID()
		case "UserUuid":
			return m.User().Uuid()
		case "UserRolesUuid":
			return m.User().Roles()
		case "UserPlatform":
			return m.User().Runtime().Platform()
		case "UserSaaS":
			return m.User().Runtime().SaaS()
		}
	default:
		return nil
	}
	return nil
}

func (this ConditionExpr) IsIgnoreEmptyParma(m TokenValue) bool {
	if !this.ignoreEmptyParma {
		return false
	}

	if this.tokenType != PARAM {
		return false
	}

	param := this.GetTokenValue(m)

	if param == "" || param == nil {
		return true
	}

	return false
}

func (this *ConditionExpr) SetOption(opts ...ExprOption) *ConditionExpr {
	for i := 0; i < len(opts); i++ {
		opts[i](this)
	}
	return this
}

func Operator(v ConditionOperator) ExprOption {
	return func(option *ConditionExpr) {
		option.operator = v
	}
}

func StringOperator(op string) ExprOption {
	return func(option *ConditionExpr) {
		option.operator = ToConditionOperator(op)
	}
}

func Token(token string, tType TokenType) ExprOption {
	return func(option *ConditionExpr) {
		option.token = token
		option.tokenType = tType
	}
}

func IgnoreEmptyParma(v bool) ExprOption {
	return func(option *ConditionExpr) {
		option.ignoreEmptyParma = v
	}
}

func FieldSqlFn(fn, fnParam string) ExprOption {
	return func(option *ConditionExpr) {
		option.fieldSqlFunc = fn
		option.fieldSqlFuncParam = fnParam
	}
}

func NewExpr(rResource, rField string, opts ...ExprOption) *ConditionExpr {
	expr := &ConditionExpr{
		field:             rField,
		fieldResource:     rResource,
		token:             "",
		tokenType:         STRING,
		operator:          EQ,
		ignoreEmptyParma:  false,
		fieldSqlFunc:      "",
		fieldSqlFuncParam: "",
	}
	expr.SetOption(opts...)
	return expr
}

func GetDBOperator(op string) ConditionOperator {
	ops := sqlgen.DefaultDialectOptions().BooleanOperatorLookup
	for t, v := range ops {
		if string(v) == strings.ToUpper(op) {
			return t
		}
	}
	return exp.EqOp
}