package api

import (
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"net/http"

	"github.com/go-chi/chi/v5"
	"github.com/insertr/insertr/internal/auth"
	"github.com/insertr/insertr/internal/db"
	"github.com/insertr/insertr/internal/engine"
	"github.com/insertr/insertr/internal/sites"
)

// ContentHandler handles all content-related HTTP requests
type ContentHandler struct {
	repository  db.ContentRepository
	authService *auth.AuthService
	siteManager *sites.SiteManager
	engine      *engine.ContentEngine
}

// NewContentHandler creates a new content handler
func NewContentHandler(database *db.Database, authService *auth.AuthService) *ContentHandler {
	// Create repository for all database operations
	repository := database.NewContentRepository()

	return &ContentHandler{
		repository:  repository,
		authService: authService,
		siteManager: nil, // Will be set via SetSiteManager
		engine:      engine.NewContentEngine(repository),
	}
}

// SetSiteManager sets the site manager for file enhancement
func (h *ContentHandler) SetSiteManager(siteManager *sites.SiteManager) {
	h.siteManager = siteManager
}

// GetContent handles GET /api/content/{id}
func (h *ContentHandler) GetContent(w http.ResponseWriter, r *http.Request) {
	contentID := chi.URLParam(r, "id")
	siteID := r.URL.Query().Get("site_id")

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	content, err := h.repository.GetContent(context.Background(), siteID, contentID)
	if err != nil {
		if err == sql.ErrNoRows {
			http.Error(w, "Content not found", http.StatusNotFound)
			return
		}
		http.Error(w, fmt.Sprintf("Database error: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(content)
}

// GetAllContent handles GET /api/content with site_id parameter
func (h *ContentHandler) GetAllContent(w http.ResponseWriter, r *http.Request) {
	siteID := r.URL.Query().Get("site_id")
	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	contentMap, err := h.repository.GetAllContent(context.Background(), siteID)
	if err != nil {
		http.Error(w, fmt.Sprintf("Database error: %v", err), http.StatusInternalServerError)
		return
	}

	// Convert map to slice for consistent API response
	var content []db.ContentItem
	for _, item := range contentMap {
		content = append(content, item)
	}

	response := db.ContentResponse{Content: content}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(response)
}

// GetBulkContent handles POST /api/content/bulk for batch fetching
func (h *ContentHandler) GetBulkContent(w http.ResponseWriter, r *http.Request) {
	siteID := r.URL.Query().Get("site_id")
	contentIDs := r.URL.Query()["ids"]

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	if len(contentIDs) == 0 {
		http.Error(w, "at least one content ID is required", http.StatusBadRequest)
		return
	}

	contentMap, err := h.repository.GetBulkContent(context.Background(), siteID, contentIDs)
	if err != nil {
		http.Error(w, fmt.Sprintf("Database error: %v", err), http.StatusInternalServerError)
		return
	}

	// Convert map to slice for consistent API response
	var content []db.ContentItem
	for _, item := range contentMap {
		content = append(content, item)
	}

	response := db.ContentResponse{Content: content}
	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(response)
}

// CreateOrUpdateContent handles POST /api/content for creating/updating content
func (h *ContentHandler) CreateOrUpdateContent(w http.ResponseWriter, r *http.Request) {
	userInfo, authErr := h.authService.ExtractUserFromRequest(r)
	if authErr != nil {
		http.Error(w, "Authentication required", http.StatusUnauthorized)
		return
	}

	var req CreateContentRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, fmt.Sprintf("Invalid JSON: %v", err), http.StatusBadRequest)
		return
	}

	// Use engine to generate ID from HTML structure
	result, err := h.engine.ProcessContent(engine.ContentInput{
		HTML:     []byte(req.HTMLMarkup),
		FilePath: req.FilePath,
		SiteID:   req.SiteID,
		Mode:     engine.IDGeneration,
	})
	if err != nil {
		http.Error(w, fmt.Sprintf("Failed to process content: %v", err), http.StatusInternalServerError)
		return
	}

	if len(result.Elements) == 0 {
		http.Error(w, "No content elements found in markup", http.StatusBadRequest)
		return
	}

	contentID := result.Elements[0].ID

	// Check if content already exists
	existingContent, _ := h.repository.GetContent(context.Background(), req.SiteID, contentID)

	var content *db.ContentItem
	if existingContent == nil {
		// Create new content
		content, err = h.repository.CreateContent(
			context.Background(),
			req.SiteID,
			contentID,
			req.HTMLContent,
			req.OriginalTemplate,
			userInfo.ID,
		)
	} else {
		// Update existing content - this would need UpdateContent method in repository
		// For now, we'll return the existing content
		content = existingContent
	}

	if err != nil {
		http.Error(w, fmt.Sprintf("Failed to save content: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(content)
}

// DeleteContent handles DELETE /api/content/{id}
func (h *ContentHandler) DeleteContent(w http.ResponseWriter, r *http.Request) {
	_, authErr := h.authService.ExtractUserFromRequest(r)
	if authErr != nil {
		http.Error(w, "Authentication required", http.StatusUnauthorized)
		return
	}

	contentID := chi.URLParam(r, "id")
	siteID := r.URL.Query().Get("site_id")

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	// Note: DeleteContent method would need to be added to repository interface
	// For now, return not implemented
	_ = contentID // Suppress unused variable warning
	http.Error(w, "Delete operation not yet implemented", http.StatusNotImplemented)
}

// UpdateContent handles PUT /api/content/{id}
func (h *ContentHandler) UpdateContent(w http.ResponseWriter, r *http.Request) {
	contentID := chi.URLParam(r, "id")
	siteID := r.URL.Query().Get("site_id")

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	var req struct {
		HTMLContent string `json:"html_content"`
	}
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "Invalid JSON", http.StatusBadRequest)
		return
	}

	userInfo, authErr := h.authService.ExtractUserFromRequest(r)
	if authErr != nil {
		http.Error(w, "Authentication required", http.StatusUnauthorized)
		return
	}

	// Check if content exists
	existingContent, err := h.repository.GetContent(context.Background(), siteID, contentID)
	if err != nil {
		if err == sql.ErrNoRows {
			http.Error(w, "Content not found", http.StatusNotFound)
			return
		}
		http.Error(w, fmt.Sprintf("Database error: %v", err), http.StatusInternalServerError)
		return
	}

	if existingContent == nil {
		http.Error(w, "Content not found", http.StatusNotFound)
		return
	}

	// Update content using repository
	updatedContent, err := h.repository.UpdateContent(context.Background(), siteID, contentID, req.HTMLContent, userInfo.ID)
	if err != nil {
		http.Error(w, fmt.Sprintf("Failed to update content: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(updatedContent)
}

// ReorderCollection handles PUT /api/collections/{id}/reorder
func (h *ContentHandler) ReorderCollection(w http.ResponseWriter, r *http.Request) {
	collectionID := chi.URLParam(r, "id")
	siteID := r.URL.Query().Get("site_id")

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	var req ReorderCollectionRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, "Invalid JSON", http.StatusBadRequest)
		return
	}

	if len(req.Items) == 0 {
		http.Error(w, "Items array cannot be empty", http.StatusBadRequest)
		return
	}

	userInfo, authErr := h.authService.ExtractUserFromRequest(r)
	if authErr != nil {
		http.Error(w, "Authentication required", http.StatusUnauthorized)
		return
	}

	// Use repository for reordering
	err := h.repository.ReorderCollectionItems(context.Background(), siteID, collectionID, req.Items, userInfo.ID)
	if err != nil {
		http.Error(w, fmt.Sprintf("Failed to reorder collection: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	response := map[string]interface{}{
		"success": true,
		"message": fmt.Sprintf("Successfully reordered %d items", len(req.Items)),
	}
	json.NewEncoder(w).Encode(response)
}

// Stub handlers for remaining endpoints - will implement as needed

// GetContentVersions handles GET /api/content/{id}/versions
func (h *ContentHandler) GetContentVersions(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Content versioning not yet implemented", http.StatusNotImplemented)
}

// RollbackContent handles POST /api/content/{id}/rollback
func (h *ContentHandler) RollbackContent(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Content rollback not yet implemented", http.StatusNotImplemented)
}

// GetAllCollections handles GET /api/collections
func (h *ContentHandler) GetAllCollections(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Get all collections not yet implemented", http.StatusNotImplemented)
}

// UpdateCollectionItem handles PUT /api/collections/{id}/items/{item_id}
func (h *ContentHandler) UpdateCollectionItem(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Update collection item not yet implemented", http.StatusNotImplemented)
}

// DeleteCollectionItem handles DELETE /api/collections/{id}/items/{item_id}
func (h *ContentHandler) DeleteCollectionItem(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Delete collection item not yet implemented", http.StatusNotImplemented)
}

// EnhanceSite handles POST /api/enhance
func (h *ContentHandler) EnhanceSite(w http.ResponseWriter, r *http.Request) {
	http.Error(w, "Site enhancement not yet implemented", http.StatusNotImplemented)
}

// GetAuthToken handles GET /api/auth/token - provides mock tokens in dev mode
func (h *ContentHandler) GetAuthToken(w http.ResponseWriter, r *http.Request) {
	// Only provide mock tokens in development mode
	if !h.authService.IsDevMode() {
		http.Error(w, "Mock authentication only available in development mode", http.StatusForbidden)
		return
	}

	// Generate a mock JWT token
	mockToken, err := h.authService.CreateMockJWT("dev-user", "dev@localhost", "Development User")
	if err != nil {
		http.Error(w, fmt.Sprintf("Failed to create mock token: %v", err), http.StatusInternalServerError)
		return
	}

	response := map[string]interface{}{
		"token":      mockToken,
		"token_type": "Bearer",
		"expires_in": 86400, // 24 hours
		"user": map[string]string{
			"id":    "dev-user",
			"email": "dev@localhost",
			"name":  "Development User",
		},
		"dev_mode": true,
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(response)
}

// GetCollection handles GET /api/collections/{id}
func (h *ContentHandler) GetCollection(w http.ResponseWriter, r *http.Request) {
	collectionID := chi.URLParam(r, "id")
	siteID := r.URL.Query().Get("site_id")

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	collection, err := h.repository.GetCollection(context.Background(), siteID, collectionID)
	if err != nil {
		if err == sql.ErrNoRows {
			http.Error(w, "Collection not found", http.StatusNotFound)
			return
		}
		http.Error(w, fmt.Sprintf("Database error: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(collection)
}

// GetCollectionItems handles GET /api/collections/{id}/items
func (h *ContentHandler) GetCollectionItems(w http.ResponseWriter, r *http.Request) {
	collectionID := chi.URLParam(r, "id")
	siteID := r.URL.Query().Get("site_id")

	if siteID == "" {
		http.Error(w, "site_id parameter is required", http.StatusBadRequest)
		return
	}

	items, err := h.repository.GetCollectionItems(context.Background(), siteID, collectionID)
	if err != nil {
		http.Error(w, fmt.Sprintf("Database error: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(items)
}

// CreateCollectionItem handles POST /api/collections/{id}/items
func (h *ContentHandler) CreateCollectionItem(w http.ResponseWriter, r *http.Request) {
	userInfo, authErr := h.authService.ExtractUserFromRequest(r)
	if authErr != nil {
		http.Error(w, "Authentication required", http.StatusUnauthorized)
		return
	}

	collectionID := chi.URLParam(r, "id")

	var req CreateCollectionItemRequest
	if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
		http.Error(w, fmt.Sprintf("Invalid JSON: %v", err), http.StatusBadRequest)
		return
	}

	if req.SiteID == "" || req.CollectionID == "" {
		req.SiteID = r.URL.Query().Get("site_id")
		req.CollectionID = collectionID
	}

	if req.SiteID == "" {
		http.Error(w, "site_id is required", http.StatusBadRequest)
		return
	}

	if req.TemplateID == 0 {
		req.TemplateID = 1 // Default to first template
	}

	// Use atomic collection item creation from repository
	createdItem, err := h.repository.CreateCollectionItemAtomic(
		context.Background(),
		req.SiteID,
		req.CollectionID,
		req.TemplateID,
		userInfo.ID,
	)
	if err != nil {
		http.Error(w, fmt.Sprintf("Failed to create collection item: %v", err), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.WriteHeader(http.StatusCreated)
	json.NewEncoder(w).Encode(createdItem)
}

// RegisterRoutes registers all the content API routes
func (h *ContentHandler) RegisterRoutes(r chi.Router) {
	r.Route("/api", func(r chi.Router) {
		// =============================================================================
		// CONTENT MANAGEMENT - Individual content items
		// =============================================================================
		r.Route("/content", func(r chi.Router) {
			// Public routes (no auth required)
			r.Get("/bulk", h.GetBulkContent) // GET /api/content/bulk?site_id=X&ids=a,b,c
			r.Get("/{id}", h.GetContent)     // GET /api/content/{id}?site_id=X
			r.Get("/", h.GetAllContent)      // GET /api/content?site_id=X

			// Protected routes (require authentication)
			r.Group(func(r chi.Router) {
				r.Use(h.authService.RequireAuth)
				r.Post("/", h.CreateOrUpdateContent) // POST /api/content (upsert)
				r.Put("/{id}", h.UpdateContent)      // PUT /api/content/{id}?site_id=X
				r.Delete("/{id}", h.DeleteContent)   // DELETE /api/content/{id}?site_id=X

				// Version control sub-routes
				r.Get("/{id}/versions", h.GetContentVersions) // GET /api/content/{id}/versions?site_id=X
				r.Post("/{id}/rollback", h.RollbackContent)   // POST /api/content/{id}/rollback
			})
		})

		// =============================================================================
		// COLLECTION MANAGEMENT - Groups of related content
		// =============================================================================
		r.Route("/collections", func(r chi.Router) {
			// Public routes
			r.Get("/", h.GetAllCollections)            // GET /api/collections?site_id=X
			r.Get("/{id}", h.GetCollection)            // GET /api/collections/{id}?site_id=X
			r.Get("/{id}/items", h.GetCollectionItems) // GET /api/collections/{id}/items?site_id=X

			// Protected routes
			r.Group(func(r chi.Router) {
				r.Use(h.authService.RequireAuth)
				r.Post("/{id}/items", h.CreateCollectionItem)             // POST /api/collections/{id}/items
				r.Put("/{id}/items/{item_id}", h.UpdateCollectionItem)    // PUT /api/collections/{id}/items/{item_id}
				r.Delete("/{id}/items/{item_id}", h.DeleteCollectionItem) // DELETE /api/collections/{id}/items/{item_id}?site_id=X

				// Bulk operations
				r.Put("/{id}/reorder", h.ReorderCollection) // PUT /api/collections/{id}/reorder?site_id=X
			})
		})

		// =============================================================================
		// AUTHENTICATION - Development token endpoint
		// =============================================================================
		r.Route("/auth", func(r chi.Router) {
			r.Get("/token", h.GetAuthToken) // GET /api/auth/token (dev mode only)
		})

		// =============================================================================
		// SITE OPERATIONS - Site-level functionality
		// =============================================================================
		r.Group(func(r chi.Router) {
			r.Use(h.authService.RequireAuth)
			r.Post("/enhance", h.EnhanceSite) // POST /api/enhance?site_id=X
		})
	})
}