feat: add file upload for materials (PDF/DOCX) with ingestion pipeline

internal/httpapi/material_upload.go

@@ -0,0 +1,67 @@
+package httpapi
+
+import (
+	"io"
+	"net/http"
+	"strings"
+
+	"tutor/internal/ingestion"
+	"tutor/internal/ontology"
+)
+
+func (h Handler) uploadMaterial(w http.ResponseWriter, r *http.Request) {
+	if h.ontology == nil {
+		writeError(w, http.StatusNotFound, "ontology not configured")
+		return
+	}
+
+	if err := r.ParseMultipartForm(32 << 20); err != nil {
+		writeError(w, http.StatusBadRequest, "invalid multipart form")
+		return
+	}
+
+	file, header, err := r.FormFile("file")
+	if err != nil {
+		writeError(w, http.StatusBadRequest, "file field required")
+		return
+	}
+	defer file.Close()
+
+	if !ingestion.IsSupported(header.Filename) {
+		writeError(w, http.StatusBadRequest, "unsupported file format; supported: .md, .markdown, .pdf, .docx")
+		return
+	}
+
+	data, err := io.ReadAll(file)
+	if err != nil {
+		writeError(w, http.StatusInternalServerError, "failed to read file")
+		return
+	}
+
+	result, err := ingestion.ParseFromBytes(header.Filename, data)
+	if err != nil {
+		if strings.Contains(err.Error(), "unsupported") {
+			writeError(w, http.StatusBadRequest, "parse error: "+err.Error())
+			return
+		}
+		writeError(w, http.StatusInternalServerError, "parse error: "+err.Error())
+		return
+	}
+
+	title := r.FormValue("title")
+	if title == "" {
+		title = result.Title
+	}
+
+	ingestResult, err := h.ontology.Ingest(ontology.IngestInput{
+		Title:      title,
+		SourceType: result.Format,
+		Body:       result.Body,
+	})
+	if err != nil {
+		writeError(w, http.StatusBadRequest, err.Error())
+		return
+	}
+
+	writeJSON(w, http.StatusCreated, ingestResult)
+}