// Copyright (c) 2024-2026 Celestino Amoroso (celestino.amoroso@gmail.com).
// All rights reserved.

// expr-context.go
package kern

// ----Expression Context
type ExprContext interface {
	Clone() ExprContext
	SetParent(ctx ExprContext)
	GetParent() (ctx ExprContext)
	GetGlobal() (ctx ExprContext)
	GetVar(varName string) (value any, exists bool)
	GetLast() any
	SetVar(varName string, value any)
	UnsafeSetVar(varName string, value any)

	EnumVars(func(name string) (accept bool)) (varNames []string)
	VarCount() int
	DeleteVar(varName string)

	EnumFuncs(func(name string) (accept bool)) (funcNames []string)
	FuncCount() int
	DeleteFunc(funcName string)

	GetLocalFuncInfo(name string) (info ExprFunc, exists bool)
	GetFuncInfo(name string) (item ExprFunc, exists bool)
	Call(name string, args map[string]any) (result any, err error)
	RegisterFuncInfo(info ExprFunc)
	RegisterFunc(name string, f Functor, returnType string, param []ExprFuncParam) (funcInfo ExprFunc, err error)

	ToDict() (dict *DictType)
	ToString(opt FmtOpt) string
}

func ContextToDict(ctx ExprContext) (dict *DictType) {
	var keys []string
	// Variables
	keys = ctx.EnumVars(nil)
	vars := MakeDict()
	for _, key := range keys {
		value, _ := ctx.GetVar(key)
		vars.SetItem(key, value)
	}

	// Functions
	keys = ctx.EnumFuncs(func(name string) bool { return true })
	funcs := MakeDict()
	for _, key := range keys {
		funcInfo, _ := ctx.GetFuncInfo(key)
		funcs.SetItem(key, funcInfo)
	}

	dict = MakeDict()
	dict.SetItem("vars", vars)
	dict.SetItem("funcs", funcs)
	return
}

func ContextToString(ctx ExprContext, opt FmtOpt) string {
	dict := ctx.ToDict()
	return dict.ToString(opt)
}