package main

import (
	"errors"
	"net/http"
	"strconv"

	"github.com/FernandoVideira/LK_API_Temp/internal/store"
	"github.com/go-chi/chi/v5"
)

type postKey string

const postCtx postKey = "post"

type CreatePostPayload struct {
	Title   string   `json:"title" validate:"required,max=100"`
	Content string   `json:"content" validate:"required,max=1000"`
	Tags    []string `json:"tags"`
}

// CreatePost godoc
//
//	@Summary		Creates a new Post
//	@Description	Creates a new Post
//	@Tags			posts
//	@Accept			json
//	@Produce		json
//	@Param			in	body		CreatePostPayload	true	"Post Payload"
//	@Success		200	{object}	store.Post
//	@Failure		400	{object}	error
//	@Failure		404	{object}	error
//	@Failure		500	{object}	error
//	@Security		ApiKeyAuth
//	@Router			/posts [post]
func (api *api) createPostHandler(w http.ResponseWriter, r *http.Request) {
	var payload CreatePostPayload
	if err := readJSON(w, r, &payload); err != nil {
		api.badRequestError(w, r, err)
		return
	}

	if err := Validate.Struct(payload); err != nil {
		api.badRequestError(w, r, err)
		return
	}

	user := getUserFromContext(r)

	post := &store.Post{
		UserID:  user.ID,
		Title:   payload.Title,
		Content: payload.Content,
		Tags:    payload.Tags,
	}

	ctx := r.Context()

	if err := api.store.Posts.Create(ctx, post); err != nil {
		api.internalServerError(w, r, err)
		return
	}

	if err := api.jsonResponse(w, http.StatusCreated, post); err != nil {
		api.internalServerError(w, r, err)
		return
	}
}

// GetPost godoc
//
//	@Summary		Fetches a Post
//	@Description	Fetches a Post by ID
//	@Tags			posts
//	@Accept			json
//	@Produce		json
//	@Param			id	path		int	true	"Post ID"
//	@Success		200	{object}	store.Post
//	@Failure		400	{object}	error
//	@Failure		404	{object}	error
//	@Failure		500	{object}	error
//	@Security		ApiKeyAuth
//	@Router			/posts/{id} [get]
func (api *api) getPostHandler(w http.ResponseWriter, r *http.Request) {
	post := getPostFromContext(r)

	comments, err := api.store.Comments.GetByPostID(r.Context(), post.ID)
	if err != nil {
		api.internalServerError(w, r, err)
		return
	}

	post.Comments = comments

	if err := api.jsonResponse(w, http.StatusOK, post); err != nil {
		api.internalServerError(w, r, err)
		return
	}
}

type UpdatePostPayload struct {
	Title   *string `json:"title" validate:"omitempty,max=100"`
	Content *string `json:"content" validate:"omitempty,max=1000"`
}

// UpdatePost godoc
//
//	@Summary		Update a Post
//	@Description	Update a Post by ID
//	@Tags			posts
//	@Accept			json
//	@Produce		json
//	@Param			id	path		int					true	"Post ID"
//	@Param			in	body		UpdatePostPayload	true	"Post Payload"
//	@Success		200	{object}	store.Post
//	@Failure		400	{object}	error
//	@Failure		404	{object}	error
//	@Failure		500	{object}	error
//	@Security		ApiKeyAuth
//	@Router			/posts/{id} [patch]
func (api *api) updatePostHandler(w http.ResponseWriter, r *http.Request) {
	post := getPostFromContext(r)

	var payload UpdatePostPayload
	if err := readJSON(w, r, &payload); err != nil {
		api.badRequestError(w, r, err)
		return
	}

	if err := Validate.Struct(payload); err != nil {
		api.badRequestError(w, r, err)
		return
	}

	if payload.Content != nil {
		post.Content = *payload.Content
	}

	if payload.Title != nil {
		post.Title = *payload.Title
	}

	if err := api.store.Posts.Update(r.Context(), post); err != nil {
		switch {
		case errors.Is(err, store.ErrNotFound):
			api.conflictError(w, r, err)
		default:
			api.internalServerError(w, r, err)
		}
		return
	}

	if err := api.jsonResponse(w, http.StatusOK, post); err != nil {
		api.internalServerError(w, r, err)
		return
	}
}

// DeletePost godoc
//
//	@Summary		Deletes a Post
//	@Description	Deletse a Post by ID
//	@Tags			posts
//	@Accept			json
//	@Produce		json
//	@Param			id	path		int	true	"Post ID"
//	@Success		204	{object}	string
//	@Failure		404	{object}	error
//	@Failure		500	{object}	error
//	@Security		ApiKeyAuth
//	@Router			/posts/{id} [delete]
func (api *api) deletePostHandler(w http.ResponseWriter, r *http.Request) {
	idParam := chi.URLParam(r, "id")
	id, err := strconv.ParseInt(idParam, 10, 64)
	if err != nil {
		api.badRequestError(w, r, err)
		return
	}
	ctx := r.Context()

	if err := api.store.Posts.Delete(ctx, id); err != nil {
		switch {
		case errors.Is(err, store.ErrNotFound):
			api.notFoundError(w, r, err)
		default:
			api.internalServerError(w, r, err)
		}
		return
	}

	w.WriteHeader(http.StatusNoContent)
}

func getPostFromContext(r *http.Request) *store.Post {
	post, _ := r.Context().Value(postCtx).(*store.Post)
	return post
}