package engine

import (
	"context"
	"fmt"
	"slices"
	"sort"
	"strings"

	"golang.org/x/net/html"
)

// addContentAttributes adds data-content-id attribute only
func (e *ContentEngine) addContentAttributes(node *html.Node, contentID string) {
	// Add data-content-id attribute
	SetAttribute(node, "data-content-id", contentID)
}

// injectContent injects content from database into elements
func (e *ContentEngine) injectContent(elements []ProcessedElement, siteID string) error {
	for i := range elements {
		elem := &elements[i]

		// Get content from database by ID - FIXED: Use context.Background() instead of nil
		contentItem, err := e.client.GetContent(context.Background(), siteID, elem.ID)
		if err != nil {
			// Content not found - skip silently (enhancement mode should not fail on missing content)
			continue
		}

		if contentItem != nil {
			// Inject the content into the element
			elem.Content = contentItem.HTMLContent

			// Update injector siteID for this operation
			// HACK: I do not like this. Injector refactor?
			e.injector.siteID = siteID
			e.injector.injectHTMLContent(elem.Node, contentItem.HTMLContent)
		}
	}
	return nil
}

// extractHTMLContent extracts the inner HTML content from a node
func (e *ContentEngine) extractHTMLContent(node *html.Node) string {
	var content strings.Builder

	// Render all child nodes in order to preserve HTML structure
	for child := node.FirstChild; child != nil; child = child.NextSibling {
		if err := html.Render(&content, child); err == nil {
			// All nodes (text and element) rendered in correct order
		}
	}

	return strings.TrimSpace(content.String())
}

// extractOriginalTemplate extracts the outer HTML of the element (including the element itself)
func (e *ContentEngine) extractOriginalTemplate(node *html.Node) string {
	var buf strings.Builder
	if err := html.Render(&buf, node); err != nil {
		return ""
	}
	return buf.String()
}

// extractStructureSignature creates a content-agnostic signature for template comparison
// This only considers DOM structure and class attributes, completely ignoring text content
func (e *ContentEngine) extractStructureSignature(node *html.Node) string {
	var signature strings.Builder

	e.walkNodes(node, func(n *html.Node) {
		if n.Type == html.ElementNode {
			// Get classes for this element
			classes := GetClasses(n)
			if len(classes) > 0 {
				// Sort classes for consistent comparison
				sortedClasses := make([]string, len(classes))
				copy(sortedClasses, classes)
				sort.Strings(sortedClasses)

				// Add to signature: element[class1,class2,...]
				signature.WriteString(fmt.Sprintf("%s[%s];", n.Data, strings.Join(sortedClasses, ",")))
			} else {
				// Element with no classes
				signature.WriteString(fmt.Sprintf("%s[];", n.Data))
			}
		}
		// Completely ignore text nodes and their content
	})

	return signature.String()
}

// extractTemplateForStorage extracts template HTML while preserving content but removing data-content-id attributes
func (e *ContentEngine) extractTemplateForStorage(node *html.Node) string {
	// Clone the node to avoid modifying the original
	clonedNode := e.cloneNode(node)

	// Remove all data-content-id attributes but preserve all content
	e.walkNodes(clonedNode, func(n *html.Node) {
		if n.Type == html.ElementNode {
			// Remove data-content-id attribute
			e.removeAttribute(n, "data-content-id")
		}
	})

	var buf strings.Builder
	if err := html.Render(&buf, clonedNode); err != nil {
		return ""
	}
	return buf.String()
}

// removeAttribute removes an attribute from an HTML node
func (e *ContentEngine) removeAttribute(n *html.Node, key string) {
	for i, attr := range n.Attr {
		if attr.Key == key {
			n.Attr = slices.Delete(n.Attr, i, i+1)
			break
		}
	}
}

// hasClass checks if a node has a specific class
func (e *ContentEngine) hasClass(n *html.Node, className string) bool {
	for _, attr := range n.Attr {
		if attr.Key == "class" {
			classes := strings.Fields(attr.Val)
			if slices.Contains(classes, className) {
				return true
			}
		}
	}
	return false
}

// getPlaceholderForElement returns appropriate placeholder text for different element types
func (e *ContentEngine) getPlaceholderForElement(elementType string) string {
	placeholders := map[string]string{
		"h1":         "Heading 1",
		"h2":         "Heading 2",
		"h3":         "Heading 3",
		"h4":         "Heading 4",
		"h5":         "Heading 5",
		"h6":         "Heading 6",
		"p":          "Paragraph text",
		"span":       "Text",
		"div":        "Content block",
		"button":     "Button",
		"a":          "Link text",
		"li":         "List item",
		"blockquote": "Quote text",
	}

	if placeholder, exists := placeholders[elementType]; exists {
		return placeholder
	}
	return "Enter content..."
}