package themes_handler

import (
	"strconv"
	"strings"
	"unicode/utf8"

	"autolibrary.top/webserver/backend/models/themes_model"
	"autolibrary.top/webserver/utils"

	"github.com/gin-gonic/gin"
)

func parseThemeID(c *gin.Context) (uint, error) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil || id == 0 {
		return 0, strconv.ErrSyntax
	}
	return uint(id), nil
}

func (h *Handler) PutThemeByID(c *gin.Context) {
	theme, ok := h.ownTheme(c)
	if !ok {
		return
	}
	var update struct {
		Name          string   `json:"name"`
		Brief         string   `json:"brief"`
		Description   string   `json:"description"`
		NeedTheme     string   `json:"need_theme"`
		Tags          []string `json:"tags"`
		Version       string   `json:"version"`
		CompatVersion string   `json:"compat_version"`
		PreviewURL    string   `json:"preview_url"`
	}
	if err := c.ShouldBindJSON(&update); err != nil {
		fail(c, 400, "Invalid theme metadata")
		return
	}
	if update.Name != "" && strings.TrimSpace(update.Name) != theme.Name {
		var count int64
		if err := h.DB.Model(&themes_model.Theme{}).Where("user_id = ? AND name = ? AND id != ?", theme.UserID, strings.TrimSpace(update.Name), theme.ID).Count(&count).Error; err != nil {
			fail(c, 500, "Unable to check theme name")
			return
		}
		if count > 0 {
			fail(c, 409, "You already have a theme with this name")
			return
		}
		theme.Name = strings.TrimSpace(update.Name)
	}
	if update.NeedTheme != "" && update.NeedTheme != "dark" && update.NeedTheme != "light" && update.NeedTheme != "both" {
		fail(c, 400, "Invalid theme mode")
		return
	}
	if utf8.RuneCountInString(update.Brief) > 50 || utf8.RuneCountInString(update.Description) > 100 {
		fail(c, 400, "Theme description is too long")
		return
	}
	if strings.TrimSpace(update.Brief) != "" {
		theme.Brief = strings.TrimSpace(update.Brief)
	}
	theme.Description = update.Description
	if update.NeedTheme != "" {
		theme.NeedTheme = update.NeedTheme
	}
	if update.Tags != nil {
		theme.Tags = update.Tags
	}
	if update.Version != "" {
		theme.Version = update.Version
	}
	theme.CompatVersion = update.CompatVersion
	// Preview changes go through the authenticated image upload endpoint. Preserve
	// the legacy field only when it refers to the theme's existing preview.
	if update.PreviewURL != "" && update.PreviewURL != theme.PreviewURL {
		fail(c, 400, "Use the preview upload endpoint to replace an image")
		return
	}
	theme.Status = themes_model.ThemePending
	theme.UpdatedAt = utils.NowInShanghai()
	if err := h.Themes.Save(theme, nil); err != nil {
		fail(c, 500, "Unable to save theme and archive")
		return
	}
	success(c, 200, "Theme updated; review required", theme)
}

func (h *Handler) DeleteThemeByID(c *gin.Context) {
	theme, ok := h.ownTheme(c)
	if !ok {
		return
	}
	if err := h.Themes.Delete(theme); err != nil {
		fail(c, 500, "Unable to delete theme")
		return
	}
	success(c, 200, "Theme deleted", nil)
}