package main

import (
	"encoding/json"
	"fmt"
	"net/http"
	"strings"

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

// handlePhotos proxies PhotoPrism's /api/v1/photos and then post-filters
// the response so only photos under the caller's BasePath are returned.
// This fixes the review/archive tab cross-user leak.
//
// Route: GET /api/sidecar/timeline  (behind requireSession)
func handlePhotos(pp *ppClient) gin.HandlerFunc {
	return func(c *gin.Context) {
		token := ctxToken(c)
		basePath := ctxBasePath(c)

		// Forward the raw query string to PhotoPrism.
		query := c.Request.URL.RawQuery

		resp, err := pp.call(c.Request.Context(), http.MethodGet, "/api/v1/photos?"+query, token, nil)
		if err != nil || !resp.OK {
			c.JSON(http.StatusBadGateway, gin.H{"error": "upstream photos request failed"})
			return
		}

		// Decode as a generic array so we can inspect Path without
		// committing to a rigid struct (PhotoPrism's photo response
		// varies between list/detail/search endpoints).
		var photos []map[string]any
		if err := json.Unmarshal(resp.Body, &photos); err != nil {
			// If it's not an array (e.g. error, single object), pass through.
			c.Data(resp.Status, "application/json", resp.Body)
			return
		}

		// If the user has no BasePath (admin/empty), return as-is.
		if basePath == "" {
			// Forward PhotoPrism's X-Count header for countPhotos().
			if count := resp.Header.Get("X-Count"); count != "" {
				c.Header("X-Count", count)
			}
			c.JSON(http.StatusOK, photos)
			return
		}

		prefix := basePath + "/"

		// Post-filter by FileName field (originals-relative path).
		filtered := make([]map[string]any, 0, len(photos))
		for _, ph := range photos {
			rawPath, ok := ph["FileName"]
			if !ok {
				continue
			}
			pathStr, ok := rawPath.(string)
			if !ok {
				continue
			}
			// Match exact basePath or basePath/...
			if pathStr == basePath || strings.HasPrefix(pathStr, prefix) {
				filtered = append(filtered, ph)
			}
		}

		// Forward X-Count header adjusted to the filtered count.
		c.Header("X-Count", itoa(len(filtered)))
		c.JSON(http.StatusOK, filtered)
	}
}

// handleNotes pages PhotoPrism's photo list to completion and returns only
// photos carrying a non-empty Caption (mule-image's "Note"), scoped to the
// caller's BasePath. Paging server-side is what makes this correct: the
// client can't tell when the *BasePath-filtered* list is exhausted (a full
// upstream page can filter down to a short — or empty — slice), but here we
// can key the loop off the raw upstream page length.
//
// Route: GET /api/sidecar/notes  (behind requireSession)
func handleNotes(pp *ppClient) gin.HandlerFunc {
	return func(c *gin.Context) {
		token := ctxToken(c)
		basePath := ctxBasePath(c)
		prefix := basePath + "/"

		const pageSize = 1000
		out := make([]map[string]any, 0, 64)
		seen := make(map[string]struct{})

		for offset := 0; ; offset += pageSize {
			path := fmt.Sprintf("/api/v1/photos?count=%d&offset=%d&merged=true&order=newest", pageSize, offset)
			resp, err := pp.call(c.Request.Context(), http.MethodGet, path, token, nil)
			if err != nil || !resp.OK {
				c.JSON(http.StatusBadGateway, gin.H{"error": "upstream photos request failed"})
				return
			}

			var photos []map[string]any
			if err := json.Unmarshal(resp.Body, &photos); err != nil {
				c.JSON(http.StatusBadGateway, gin.H{"error": "unexpected photos response"})
				return
			}
			rawLen := len(photos)

			for _, ph := range photos {
				// BasePath scope — same rule as handlePhotos.
				if basePath != "" {
					pathStr, _ := ph["FileName"].(string)
					if pathStr != basePath && !strings.HasPrefix(pathStr, prefix) {
						continue
					}
				}
				// Non-empty caption only.
				caption, _ := ph["Caption"].(string)
				if strings.TrimSpace(caption) == "" {
					continue
				}
				// Dedupe by UID — `merged` can still repeat a photo at a page seam.
				uid, _ := ph["UID"].(string)
				if uid != "" {
					if _, ok := seen[uid]; ok {
						continue
					}
					seen[uid] = struct{}{}
				}
				out = append(out, ph)
			}

			// A short upstream page means PhotoPrism has no more rows.
			if rawLen < pageSize {
				break
			}
		}

		c.JSON(http.StatusOK, out)
	}
}