package server

import (
	"net/http"
	"strconv"
	"strings"

	"github.com/go-chi/chi/v5"
	"github.com/writekitapp/writekit/internal/auth"
	"github.com/writekitapp/writekit/internal/tenant"
)

func (s *Server) publicAPIRoutes() chi.Router {
	r := chi.NewRouter()
	r.Use(s.apiKeyMiddleware)
	r.Use(s.apiRateLimitMiddleware(s.rateLimiter))

	r.Get("/posts", s.apiListPosts)
	r.Post("/posts", s.apiCreatePost)
	r.Get("/posts/{slug}", s.apiGetPost)
	r.Put("/posts/{slug}", s.apiUpdatePost)
	r.Delete("/posts/{slug}", s.apiDeletePost)

	r.Get("/settings", s.apiGetSettings)

	return r
}

func (s *Server) apiKeyMiddleware(next http.Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		tenantID, ok := r.Context().Value(tenantIDKey).(string)
		if !ok || tenantID == "" {
			jsonError(w, http.StatusUnauthorized, "unauthorized")
			return
		}

		key := extractAPIKey(r)
		if key != "" {
			db, err := s.tenantPool.Get(tenantID)
			if err != nil {
				jsonError(w, http.StatusInternalServerError, "database error")
				return
			}

			q := tenant.NewQueries(db)
			valid, err := q.ValidateAPIKey(r.Context(), key)
			if err != nil {
				jsonError(w, http.StatusInternalServerError, "validation error")
				return
			}
			if valid {
				next.ServeHTTP(w, r)
				return
			}
			jsonError(w, http.StatusUnauthorized, "invalid API key")
			return
		}

		if GetDemoInfo(r).IsDemo {
			next.ServeHTTP(w, r)
			return
		}

		userID := auth.GetUserID(r)
		if userID == "" {
			jsonError(w, http.StatusUnauthorized, "API key required")
			return
		}

		isOwner, err := s.database.IsUserTenantOwner(r.Context(), userID, tenantID)
		if err != nil || !isOwner {
			jsonError(w, http.StatusUnauthorized, "API key required")
			return
		}

		next.ServeHTTP(w, r)
	})
}

func extractAPIKey(r *http.Request) string {
	auth := r.Header.Get("Authorization")
	if strings.HasPrefix(auth, "Bearer ") {
		return strings.TrimPrefix(auth, "Bearer ")
	}
	return r.URL.Query().Get("api_key")
}

type paginatedPostsResponse struct {
	Posts  []postResponse `json:"posts"`
	Total  int            `json:"total"`
	Limit  int            `json:"limit"`
	Offset int            `json:"offset"`
}

func (s *Server) apiListPosts(w http.ResponseWriter, r *http.Request) {
	tenantID := r.Context().Value(tenantIDKey).(string)

	db, err := s.tenantPool.Get(tenantID)
	if err != nil {
		jsonError(w, http.StatusInternalServerError, "database error")
		return
	}

	limit, _ := strconv.Atoi(r.URL.Query().Get("limit"))
	offset, _ := strconv.Atoi(r.URL.Query().Get("offset"))
	tag := r.URL.Query().Get("tag")
	includeContent := r.URL.Query().Get("include") == "content"

	q := tenant.NewQueries(db)
	result, err := q.ListPostsPaginated(r.Context(), tenant.ListPostsOptions{
		Limit:  limit,
		Offset: offset,
		Tag:    tag,
	})
	if err != nil {
		jsonError(w, http.StatusInternalServerError, "failed to list posts")
		return
	}

	posts := make([]postResponse, len(result.Posts))
	for i, p := range result.Posts {
		posts[i] = postToResponse(&p, includeContent)
	}

	jsonResponse(w, http.StatusOK, paginatedPostsResponse{
		Posts:  posts,
		Total:  result.Total,
		Limit:  limit,
		Offset: offset,
	})
}

func (s *Server) apiGetPost(w http.ResponseWriter, r *http.Request) {
	tenantID := r.Context().Value(tenantIDKey).(string)
	slug := chi.URLParam(r, "slug")

	db, err := s.tenantPool.Get(tenantID)
	if err != nil {
		jsonError(w, http.StatusInternalServerError, "database error")
		return
	}

	q := tenant.NewQueries(db)
	post, err := q.GetPost(r.Context(), slug)
	if err != nil {
		jsonError(w, http.StatusInternalServerError, "failed to get post")
		return
	}
	if post == nil {
		jsonError(w, http.StatusNotFound, "post not found")
		return
	}

	jsonResponse(w, http.StatusOK, postToResponse(post, true))
}

func (s *Server) apiCreatePost(w http.ResponseWriter, r *http.Request) {
	s.createPost(w, r)
}

func (s *Server) apiUpdatePost(w http.ResponseWriter, r *http.Request) {
	s.updatePost(w, r)
}

func (s *Server) apiDeletePost(w http.ResponseWriter, r *http.Request) {
	s.deletePost(w, r)
}

var publicSettingsKeys = []string{
	"site_name",
	"site_description",
	"author_name",
	"author_role",
	"author_bio",
	"author_photo",
	"twitter_handle",
	"github_handle",
	"linkedin_handle",
	"email",
	"accent_color",
	"font",
}

func (s *Server) apiGetSettings(w http.ResponseWriter, r *http.Request) {
	tenantID := r.Context().Value(tenantIDKey).(string)

	db, err := s.tenantPool.Get(tenantID)
	if err != nil {
		jsonError(w, http.StatusInternalServerError, "database error")
		return
	}

	q := tenant.NewQueries(db)
	allSettings, err := q.GetSettings(r.Context())
	if err != nil {
		jsonError(w, http.StatusInternalServerError, "failed to get settings")
		return
	}

	result := make(map[string]string)
	for _, key := range publicSettingsKeys {
		if val, ok := allSettings[key]; ok {
			result[key] = val
		}
	}

	jsonResponse(w, http.StatusOK, result)
}