package admin

import (
	"io"
	"net/http"
	"os"
	"path/filepath"
	"strings"
)

func (s *AdminServer) handleFiles(w http.ResponseWriter, r *http.Request) {
	relPath := r.URL.Query().Get("path")
	relPath = strings.TrimPrefix(relPath, "/")
	relPath = strings.TrimPrefix(relPath, "data/")

	switch r.Method {
	case http.MethodGet:
		if relPath == "" {
			entries, err := os.ReadDir(s.dataDir)
			if err != nil {
				writeJSON(w, map[string]any{"error": err.Error()})
				return
			}
			var files []map[string]any
			for _, e := range entries {
				files = append(files, map[string]any{
					"name": e.Name(),
					"dir":  e.IsDir(),
				})
			}
			writeJSON(w, files)
			return
		}

		fullPath := filepath.Join(s.dataDir, relPath)
		info, err := os.Stat(fullPath)
		if err != nil {
			writeJSON(w, map[string]any{"error": "not found: " + relPath})
			return
		}

		if info.IsDir() {
			entries, err := os.ReadDir(fullPath)
			if err != nil {
				writeJSON(w, map[string]any{"error": err.Error()})
				return
			}
			var files []map[string]any
			for _, e := range entries {
				files = append(files, map[string]any{
					"name": e.Name(),
					"dir":  e.IsDir(),
				})
			}
			writeJSON(w, files)
			return
		}

		data, err := os.ReadFile(fullPath)
		if err != nil {
			writeJSON(w, map[string]any{"error": "read error: " + err.Error()})
			return
		}
		writeJSON(w, map[string]any{
			"name":    info.Name(),
			"content": string(data),
			"path":    relPath,
		})

	case http.MethodPut, http.MethodPost:
		if relPath == "" {
			writeJSON(w, map[string]any{"error": "missing path"})
			return
		}
		fullPath := filepath.Join(s.dataDir, relPath)

		body, err := io.ReadAll(r.Body)
		if err != nil {
			writeJSON(w, map[string]any{"error": "read body: " + err.Error()})
			return
		}

		var oldContent []byte
		if existing, err := snapshotFile(fullPath); err == nil {
			oldContent = existing
		}

		dir := filepath.Dir(fullPath)
		if err := os.MkdirAll(dir, 0755); err != nil {
			writeJSON(w, map[string]any{"error": "mkdir: " + err.Error()})
			return
		}

		if err := os.WriteFile(fullPath, body, 0644); err != nil {
			writeJSON(w, map[string]any{"error": "write error: " + err.Error()})
			return
		}

		isCreate := oldContent == nil
		desc := "Updated file " + relPath
		if isCreate {
			desc = "Created file " + relPath
		}
		s.undoStack.Push(ChangeDesc{
			Description: desc,
			FilePath:    fullPath,
			OldContent:  oldContent,
			NewContent:  body,
			IsCreate:    isCreate,
		})
		writeJSON(w, map[string]any{"ok": true, "path": relPath})

	case http.MethodDelete:
		if relPath == "" {
			writeJSON(w, map[string]any{"error": "missing path"})
			return
		}
		fullPath := filepath.Join(s.dataDir, relPath)
		oldContent, _ := snapshotFile(fullPath)
		if err := os.Remove(fullPath); err != nil {
			writeJSON(w, map[string]any{"error": "delete error: " + err.Error()})
			return
		}
		s.undoStack.Push(ChangeDesc{
			Description: "Deleted file " + relPath,
			FilePath:    fullPath,
			OldContent:  oldContent,
			IsDelete:    true,
		})
		writeJSON(w, map[string]any{"ok": true, "path": relPath})

	default:
		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
	}
}