Initial commit: party-mix-app with prefetch cache, audio preload optimizations

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/backend/internal/handlers/party.go

@@ -0,0 +1,173 @@
+package handlers
+
+import (
+	"math/rand"
+	"net/http"
+	"time"
+
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+	"github.com/toyffee/party-mix/internal/models"
+	"gorm.io/gorm"
+)
+
+const codeChars = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789"
+
+func generateCode() string {
+	b := make([]byte, 6)
+	for i := range b {
+		b[i] = codeChars[rand.Intn(len(codeChars))]
+	}
+	return string(b)
+}
+
+type createPartyReq struct {
+	Name       string `json:"name" binding:"required"`
+	TelegramID int64  `json:"telegram_id"`
+}
+
+func CreateParty(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		var req createPartyReq
+		if err := c.ShouldBindJSON(&req); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+			return
+		}
+		party := models.Party{
+			ID:         uuid.NewString(),
+			Name:       req.Name,
+			Code:       generateCode(),
+			TelegramID: req.TelegramID,
+			CreatedAt:  time.Now(),
+		}
+		if err := db.Create(&party).Error; err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to create party"})
+			return
+		}
+		c.JSON(http.StatusCreated, party)
+	}
+}
+
+func GetParty(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		var party models.Party
+		err := db.Preload("Participants.Tracks").First(&party, "id = ?", c.Param("id")).Error
+		if err != nil {
+			c.JSON(http.StatusNotFound, gin.H{"error": "party not found"})
+			return
+		}
+		c.JSON(http.StatusOK, party)
+	}
+}
+
+func GetPartyByCode(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		var party models.Party
+		err := db.Preload("Participants.Tracks").First(&party, "code = ?", c.Param("code")).Error
+		if err != nil {
+			c.JSON(http.StatusNotFound, gin.H{"error": "party not found"})
+			return
+		}
+		c.JSON(http.StatusOK, party)
+	}
+}
+
+type addParticipantReq struct {
+	Name      string   `json:"name" binding:"required"`
+	Tracks    []string `json:"tracks" binding:"required"`
+	ColorBg   string   `json:"color_bg"`
+	ColorText string   `json:"color_text"`
+}
+
+func AddParticipant(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		var req addParticipantReq
+		if err := c.ShouldBindJSON(&req); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+			return
+		}
+		participant := models.Participant{
+			ID:        uuid.NewString(),
+			PartyID:   c.Param("id"),
+			Name:      req.Name,
+			ColorBg:   req.ColorBg,
+			ColorText: req.ColorText,
+			CreatedAt: time.Now(),
+		}
+		tracks := make([]models.Track, 0, len(req.Tracks))
+		for i, title := range req.Tracks {
+			tracks = append(tracks, models.Track{
+				ID:            uuid.NewString(),
+				ParticipantID: participant.ID,
+				Title:         title,
+				Position:      i,
+				CreatedAt:     time.Now(),
+			})
+		}
+		participant.Tracks = tracks
+		if err := db.Create(&participant).Error; err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to add participant"})
+			return
+		}
+		c.JSON(http.StatusCreated, participant)
+	}
+}
+
+func RemoveParticipant(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		pid := c.Param("pid")
+		db.Where("participant_id = ?", pid).Delete(&models.Track{})
+		if err := db.Delete(&models.Participant{}, "id = ?", pid).Error; err != nil {
+			c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to remove participant"})
+			return
+		}
+		c.Status(http.StatusNoContent)
+	}
+}
+
+type addHistoryReq struct {
+	Title          string `json:"title"`
+	Artist         string `json:"artist"`
+	ImgURL         string `json:"img_url"`
+	OwnerName      string `json:"owner_name"`
+	OwnerColorBg   string `json:"owner_color_bg"`
+	OwnerColorText string `json:"owner_color_text"`
+}
+
+func AddHistory(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		var req addHistoryReq
+		if err := c.ShouldBindJSON(&req); err != nil {
+			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
+			return
+		}
+		item := models.HistoryItem{
+			ID:             uuid.NewString(),
+			PartyID:        c.Param("id"),
+			Title:          req.Title,
+			Artist:         req.Artist,
+			ImgURL:         req.ImgURL,
+			OwnerName:      req.OwnerName,
+			OwnerColorBg:   req.OwnerColorBg,
+			OwnerColorText: req.OwnerColorText,
+			PlayedAt:       time.Now(),
+		}
+		db.Create(&item)
+		c.JSON(http.StatusCreated, item)
+	}
+}
+
+func GetHistory(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		var items []models.HistoryItem
+		db.Where("party_id = ?", c.Param("id")).Order("played_at desc").Limit(100).Find(&items)
+		c.JSON(http.StatusOK, items)
+	}
+}
+
+func ClearHistory(db *gorm.DB) gin.HandlerFunc {
+	return func(c *gin.Context) {
+		db.Where("party_id = ?", c.Param("id")).Delete(&models.HistoryItem{})
+		c.Status(http.StatusNoContent)
+	}
+}