ad_fun/chessstars/internal/courses/handlers.go

package courses

import (
	"net/http"
	"strconv"

	"chessstars/internal/auth"
	"chessstars/internal/httpx"
)

type Handlers struct {
	store *Store
}

func NewHandlers(store *Store) *Handlers {
	return &Handlers{store: store}
}

func pathID(r *http.Request, name string) (int64, bool) {
	v := r.PathValue(name)
	id, err := strconv.ParseInt(v, 10, 64)
	return id, err == nil
}

func canView(c *Course, u *auth.User) bool {
	if c.Visibility == "public" {
		return true
	}
	return u != nil && u.ID == c.AuthorID
}

type chapterSummary struct {
	ID      int64  `json:"id"`
	Ordinal int    `json:"ordinal"`
	Title   string `json:"title"`
}

type courseDetail struct {
	ID          int64             `json:"id"`
	Author      string            `json:"author"`
	Title       string            `json:"title"`
	Description string            `json:"description"`
	Visibility  string            `json:"visibility"`
	Variant     int               `json:"variant"`
	StartFEN    string            `json:"start_fen"`
	RuleFlags   uint32            `json:"rule_flags"`
	Chapters    []chapterSummary  `json:"chapters"`
}

func (h *Handlers) CreateCourse(w http.ResponseWriter, r *http.Request) {
	u, ok := auth.UserFromContext(r.Context())
	if !ok {
		httpx.Error(w, http.StatusUnauthorized, "not logged in")
		return
	}
	var req struct {
		Title       string `json:"title"`
		Description string `json:"description"`
		Visibility  string `json:"visibility"`
		Variant     int    `json:"variant"`
		StartFEN    string `json:"start_fen"`
		RuleFlags   uint32 `json:"rule_flags"`
	}
	if err := httpx.ReadJSON(r, &req); err != nil || req.Title == "" {
		httpx.Error(w, http.StatusBadRequest, "invalid request")
		return
	}

	c, err := h.store.CreateCourse(Course{
		AuthorID: u.ID, AuthorName: u.Username, Title: req.Title, Description: req.Description,
		Visibility: req.Visibility, Variant: req.Variant, StartFEN: req.StartFEN, RuleFlags: req.RuleFlags,
	})
	if err != nil {
		httpx.Error(w, http.StatusInternalServerError, "could not create course")
		return
	}
	httpx.WriteJSON(w, http.StatusOK, map[string]any{"ok": true, "id": c.ID})
}

func (h *Handlers) ListPublicCourses(w http.ResponseWriter, r *http.Request) {
	list, err := h.store.ListPublicCourses()
	if err != nil {
		httpx.Error(w, http.StatusInternalServerError, "list failed")
		return
	}
	httpx.WriteJSON(w, http.StatusOK, map[string]any{"ok": true, "courses": list})
}

func (h *Handlers) ListMyCourses(w http.ResponseWriter, r *http.Request) {
	u, ok := auth.UserFromContext(r.Context())
	if !ok {
		httpx.Error(w, http.StatusUnauthorized, "not logged in")
		return
	}
	list, err := h.store.ListCoursesByAuthor(u.ID)
	if err != nil {
		httpx.Error(w, http.StatusInternalServerError, "list failed")
		return
	}
	httpx.WriteJSON(w, http.StatusOK, map[string]any{"ok": true, "courses": list})
}

func (h *Handlers) GetCourse(w http.ResponseWriter, r *http.Request) {
	id, ok := pathID(r, "id")
	if !ok {
		httpx.Error(w, http.StatusBadRequest, "bad id")
		return
	}
	c, err := h.store.GetCourse(id)
	if err != nil {
		httpx.Error(w, http.StatusNotFound, "no such course")
		return
	}
	u, _ := auth.UserFromContext(r.Context())
	if !canView(c, u) {
		httpx.Error(w, http.StatusNotFound, "no such course")
		return
	}

	chapters, err := h.store.ListChaptersByCourse(c.ID)
	if err != nil {
		httpx.Error(w, http.StatusInternalServerError, "list failed")
		return
	}
	summaries := make([]chapterSummary, 0, len(chapters))
	for _, ch := range chapters {
		summaries = append(summaries, chapterSummary{ID: ch.ID, Ordinal: ch.Ordinal, Title: ch.Title})
	}

	httpx.WriteJSON(w, http.StatusOK, courseDetail{
		ID: c.ID, Author: c.AuthorName, Title: c.Title, Description: c.Description,
		Visibility: c.Visibility, Variant: c.Variant, StartFEN: c.StartFEN, RuleFlags: c.RuleFlags,
		Chapters: summaries,
	})
}

func (h *Handlers) AddChapter(w http.ResponseWriter, r *http.Request) {
	u, ok := auth.UserFromContext(r.Context())
	if !ok {
		httpx.Error(w, http.StatusUnauthorized, "not logged in")
		return
	}
	courseID, ok := pathID(r, "id")
	if !ok {
		httpx.Error(w, http.StatusBadRequest, "bad id")
		return
	}
	c, err := h.store.GetCourse(courseID)
	if err != nil {
		httpx.Error(w, http.StatusNotFound, "no such course")
		return
	}
	if c.AuthorID != u.ID {
		httpx.Error(w, http.StatusForbidden, "not your course")
		return
	}

	var req struct {
		Ordinal      int       `json:"ordinal"`
		Title        string    `json:"title"`
		Annotation   string    `json:"annotation"`
		Moves        []MoveRef `json:"moves"`
		SolutionNote string    `json:"solution_note"`
	}
	if err := httpx.ReadJSON(r, &req); err != nil || req.Title == "" {
		httpx.Error(w, http.StatusBadRequest, "invalid request")
		return
	}

	ch, err := h.store.AddChapter(Chapter{
		CourseID: c.ID, Ordinal: req.Ordinal, Title: req.Title, Annotation: req.Annotation,
		Moves: req.Moves, SolutionNote: req.SolutionNote,
	})
	if err != nil {
		httpx.Error(w, http.StatusInternalServerError, "could not add chapter")
		return
	}
	httpx.WriteJSON(w, http.StatusOK, map[string]any{"ok": true, "id": ch.ID})
}

type chapterDetail struct {
	ID           int64     `json:"id"`
	CourseID     int64     `json:"course_id"`
	Ordinal      int       `json:"ordinal"`
	Title        string    `json:"title"`
	Annotation   string    `json:"annotation"`
	Moves        []MoveRef `json:"moves"`
	SolutionNote string    `json:"solution_note"`
}

func (h *Handlers) GetChapter(w http.ResponseWriter, r *http.Request) {
	if _, ok := auth.UserFromContext(r.Context()); !ok {
		httpx.Error(w, http.StatusUnauthorized, "not logged in")
		return
	}
	courseID, ok := pathID(r, "id")
	if !ok {
		httpx.Error(w, http.StatusBadRequest, "bad course id")
		return
	}
	chapterID, ok := pathID(r, "chapterID")
	if !ok {
		httpx.Error(w, http.StatusBadRequest, "bad chapter id")
		return
	}

	ch, err := h.store.GetChapter(courseID, chapterID)
	if err != nil {
		httpx.Error(w, http.StatusNotFound, "no such chapter")
		return
	}

	httpx.WriteJSON(w, http.StatusOK, chapterDetail{
		ID: ch.ID, CourseID: ch.CourseID, Ordinal: ch.Ordinal, Title: ch.Title,
		Annotation: ch.Annotation, Moves: ch.Moves, SolutionNote: ch.SolutionNote,
	})
}