// Copyright (c) 2026 Probo Inc <hello@getprobo.com>.
//
// Permission to use, copy, modify, and/or distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
// AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
// OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.

package validator

import (
	"fmt"
	"strings"

	"go.probo.inc/probo/pkg/prosemirror"
)

// ProseMirrorDocumentContent requires non-empty string values to be valid
// ProseMirror/Tiptap JSON with root type "doc". Empty and whitespace-only
// strings are allowed.
func ProseMirrorDocumentContent() ValidatorFunc {
	return func(value any) *ValidationError {
		actualValue, isNil := dereferenceValue(value)
		if isNil {
			return nil
		}
		s, ok := actualValue.(string)
		if !ok {
			return newValidationError(ErrorCodeInvalidFormat, "value must be a string")
		}
		if strings.TrimSpace(s) == "" {
			return nil
		}
		if err := prosemirror.ValidateDocumentContentJSON(s); err != nil {
			return newValidationError(ErrorCodeInvalidFormat, err.Error())
		}
		return nil
	}
}

// ProseMirrorDocumentMaxTextLength validates that the total text content
// within a ProseMirror/Tiptap JSON document does not exceed maxLength bytes.
// Only user-visible text is counted; structural markup is excluded.
// Nil, empty, and whitespace-only values pass. Invalid JSON is skipped
// (let ProseMirrorDocumentContent handle format errors).
func ProseMirrorDocumentMaxTextLength(maxLength int) ValidatorFunc {
	return func(value any) *ValidationError {
		actualValue, isNil := dereferenceValue(value)
		if isNil {
			return nil
		}
		s, ok := actualValue.(string)
		if !ok {
			return newValidationError(ErrorCodeInvalidFormat, "value must be a string")
		}
		if strings.TrimSpace(s) == "" {
			return nil
		}
		n, err := prosemirror.Parse(s)
		if err != nil {
			return nil
		}
		if n.TextLength() > maxLength {
			return newValidationError(
				ErrorCodeTooLong,
				fmt.Sprintf("text content must be at most %d characters", maxLength),
			)
		}
		return nil
	}
}