package handlers

// folders.go — Chat folder CRUD (v0.23.1)
//
// Folders are user-scoped groupings for personal (direct) chats.
// Routes:
//   GET    /api/v1/folders
//   POST   /api/v1/folders
//   PUT    /api/v1/folders/:id
//   DELETE /api/v1/folders/:id

import (
	"net/http"
	"strings"
	"time"

	"github.com/gin-gonic/gin"

	"git.gobha.me/xcaliber/chat-switchboard/database"
)

type FolderHandler struct{}

func NewFolderHandler() *FolderHandler { return &FolderHandler{} }

type folderRow struct {
	ID         string    `json:"id"`
	Name       string    `json:"name"`
	ParentID   *string   `json:"parent_id,omitempty"`
	SortOrder  int       `json:"sort_order"`
	CreatedAt  time.Time `json:"created_at"`
	UpdatedAt  time.Time `json:"updated_at"`
}

func (h *FolderHandler) List(c *gin.Context) {
	userID := getUserID(c)
	rows, err := database.DB.QueryContext(c.Request.Context(), database.Q(`
		SELECT id, name, parent_id, sort_order, created_at, updated_at
		FROM folders
		WHERE user_id = $1
		ORDER BY sort_order, name
	`), userID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to list folders"})
		return
	}
	defer rows.Close()

	var folders []folderRow
	for rows.Next() {
		var f folderRow
		if err := rows.Scan(&f.ID, &f.Name, &f.ParentID, &f.SortOrder, &f.CreatedAt, &f.UpdatedAt); err != nil {
			continue
		}
		folders = append(folders, f)
	}
	if folders == nil {
		folders = []folderRow{}
	}
	c.JSON(http.StatusOK, gin.H{"folders": folders})
}

func (h *FolderHandler) Create(c *gin.Context) {
	userID := getUserID(c)
	var req struct {
		Name      string `json:"name" binding:"required"`
		SortOrder int    `json:"sort_order"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	req.Name = strings.TrimSpace(req.Name)
	if req.Name == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "name is required"})
		return
	}

	var f folderRow
	err := database.DB.QueryRowContext(c.Request.Context(), database.Q(`
		INSERT INTO folders (user_id, name, sort_order)
		VALUES ($1, $2, $3)
		RETURNING id, name, parent_id, sort_order, created_at, updated_at
	`), userID, req.Name, req.SortOrder).Scan(
		&f.ID, &f.Name, &f.ParentID, &f.SortOrder, &f.CreatedAt, &f.UpdatedAt)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to create folder"})
		return
	}
	c.JSON(http.StatusCreated, gin.H{"folder": f})
}

func (h *FolderHandler) Update(c *gin.Context) {
	userID := getUserID(c)
	folderID := c.Param("id")
	var req struct {
		Name      string `json:"name"`
		SortOrder *int   `json:"sort_order"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}
	if req.Name != "" {
		req.Name = strings.TrimSpace(req.Name)
	}

	res, err := database.DB.ExecContext(c.Request.Context(), database.Q(`
		UPDATE folders
		SET name       = COALESCE(NULLIF($3, ''), name),
		    sort_order = COALESCE($4, sort_order)
		WHERE id = $1 AND user_id = $2
	`), folderID, userID, req.Name, req.SortOrder)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to update folder"})
		return
	}
	if n, _ := res.RowsAffected(); n == 0 {
		c.JSON(http.StatusNotFound, gin.H{"error": "folder not found"})
		return
	}
	c.JSON(http.StatusOK, gin.H{"ok": true})
}

func (h *FolderHandler) Delete(c *gin.Context) {
	userID := getUserID(c)
	folderID := c.Param("id")

	// Unassign chats before deleting folder
	_, _ = database.DB.ExecContext(c.Request.Context(), database.Q(`
		UPDATE channels SET folder_id = NULL WHERE folder_id = $1 AND user_id = $2
	`), folderID, userID)

	res, err := database.DB.ExecContext(c.Request.Context(), database.Q(`
		DELETE FROM folders WHERE id = $1 AND user_id = $2
	`), folderID, userID)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "failed to delete folder"})
		return
	}
	if n, _ := res.RowsAffected(); n == 0 {
		c.JSON(http.StatusNotFound, gin.H{"error": "folder not found"})
		return
	}
	c.JSON(http.StatusOK, gin.H{"ok": true})
}