package photos

import (
	"io"
	"net/http"
	"strconv"
	"time"

	"github.com/gin-gonic/gin"

	"shared-album/internal/auth"
	"shared-album/internal/httpx"
)

const maxUploadSize = 50 << 20

type Handler struct {
	svc *Service
}

func NewHandler(svc *Service) *Handler { return &Handler{svc: svc} }

func (h *Handler) List(c *gin.Context) {
	limit, _ := strconv.Atoi(c.DefaultQuery("limit", "50"))
	var since *time.Time
	if raw := c.Query("since"); raw != "" {
		if t, err := time.Parse(time.RFC3339, raw); err == nil {
			since = &t
		} else if ms, err := strconv.ParseInt(raw, 10, 64); err == nil {
			t := time.UnixMilli(ms)
			since = &t
		}
	}
	list, next, err := h.svc.List(c.Request.Context(), c.Param("id"), auth.UserID(c), c.Query("cursor"), since, limit)
	if err != nil {
		httpx.RespondError(c, err)
		return
	}
	c.JSON(http.StatusOK, gin.H{"photos": list, "next_cursor": next})
}

func (h *Handler) Upload(c *gin.Context) {
	c.Request.Body = http.MaxBytesReader(c.Writer, c.Request.Body, maxUploadSize)
	form, err := c.MultipartForm()
	if err != nil {
		httpx.RespondError(c, httpx.BadRequest("invalid_request", "expected multipart form"))
		return
	}
	files := form.File["files"]
	if len(files) == 0 {
		files = form.File["file"]
	}
	if len(files) == 0 {
		httpx.RespondError(c, httpx.BadRequest("no_files", "no files provided"))
		return
	}

	created := make([]any, 0, len(files))
	for _, fh := range files {
		f, err := fh.Open()
		if err != nil {
			httpx.RespondError(c, err)
			return
		}
		data, err := io.ReadAll(io.LimitReader(f, maxUploadSize))
		f.Close()
		if err != nil {
			httpx.RespondError(c, err)
			return
		}
		p, err := h.svc.Upload(c.Request.Context(), UploadInput{
			AlbumID:  c.Param("id"),
			UserID:   auth.UserID(c),
			Filename: fh.Filename,
			MimeType: fh.Header.Get("Content-Type"),
			Data:     data,
		})
		if err != nil {
			httpx.RespondError(c, err)
			return
		}
		created = append(created, p)
	}
	c.JSON(http.StatusCreated, gin.H{"photos": created})
}

func (h *Handler) Get(c *gin.Context) {
	p, err := h.svc.Get(c.Request.Context(), c.Param("id"), auth.UserID(c))
	if err != nil {
		httpx.RespondError(c, err)
		return
	}
	c.JSON(http.StatusOK, gin.H{"photo": p})
}

type renameRequest struct {
	OriginalFilename string `json:"original_filename" binding:"required"`
}

func (h *Handler) Rename(c *gin.Context) {
	var req renameRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		httpx.RespondError(c, httpx.BadRequest("invalid_request", "original_filename is required"))
		return
	}
	p, err := h.svc.Rename(c.Request.Context(), c.Param("id"), auth.UserID(c), req.OriginalFilename)
	if err != nil {
		httpx.RespondError(c, err)
		return
	}
	c.JSON(http.StatusOK, gin.H{"photo": p})
}

func (h *Handler) Download(c *gin.Context) {
	url, err := h.svc.Download(c.Request.Context(), c.Param("id"), auth.UserID(c))
	if err != nil {
		httpx.RespondError(c, err)
		return
	}
	c.JSON(http.StatusOK, gin.H{"url": url})
}

func (h *Handler) Delete(c *gin.Context) {
	if err := h.svc.Delete(c.Request.Context(), c.Param("id"), auth.UserID(c)); err != nil {
		httpx.RespondError(c, err)
		return
	}
	c.Status(http.StatusNoContent)
}