feat(reports): store and browse report artifacts

app/web/routes.py

@@ -3,9 +3,13 @@
 
 from __future__ import annotations
 
+import csv
+import io
+import json
 import os
 
-from flask import Flask, abort, jsonify, render_template, request
+from flask import Flask, Response, abort, jsonify, render_template, request
+from werkzeug.utils import secure_filename
 
 from ..utils.constants import (
     APP_REPORT_DATA_DIR,
@@ -154,6 +158,84 @@ def register_routes(app: Flask,
 
     # --- reports -----------------------------------------------------------
 
+    @app.get("/api/reports")
+    def list_report_artifacts():
+        source = (request.args.get("source") or "").strip() or None
+        if source is not None and source not in report_sources:
+            return jsonify({"error": "unknown report source"}), 400
+        limit = request.args.get("limit", default=50, type=int)
+        try:
+            from ..db import get_connection
+            from ..db import repositories as repo
+            result = repo.list_report_artifacts(
+                get_connection(), source=source,
+                report_type=(request.args.get("type") or "").strip() or None,
+                since=(request.args.get("since") or "").strip() or None,
+                until=(request.args.get("until") or "").strip() or None,
+                limit=limit,
+                cursor=(request.args.get("cursor") or "").strip() or None,
+            )
+            return jsonify(result)
+        except ValueError as exc:
+            return jsonify({"error": str(exc)}), 400
+        except Exception as exc:
+            return jsonify({"error": f"report database unavailable: {exc}"}), 503
+
+    @app.get("/api/report-artifacts/<int:artifact_id>")
+    def get_report_artifact(artifact_id: int):
+        try:
+            from ..db import get_connection
+            from ..db import repositories as repo
+            artifact = repo.get_report_artifact(get_connection(), artifact_id)
+        except Exception as exc:
+            return jsonify({"error": f"report database unavailable: {exc}"}), 503
+        if artifact is None:
+            abort(404, "report artifact not found")
+        return jsonify(artifact)
+
+    @app.get("/api/report-artifacts/<int:artifact_id>/export")
+    def export_report_artifact(artifact_id: int):
+        try:
+            from ..db import get_connection
+            from ..db import repositories as repo
+            artifact = repo.get_report_artifact(get_connection(), artifact_id)
+        except Exception as exc:
+            return jsonify({"error": f"report database unavailable: {exc}"}), 503
+        if artifact is None:
+            abort(404, "report artifact not found")
+
+        payload = artifact["payload"]
+        export_format = (request.args.get("format") or "json").lower()
+        filename = secure_filename(os.path.basename(
+            artifact["original_path"])) or f"report-{artifact_id}"
+        if export_format == "json":
+            content = json.dumps(payload, ensure_ascii=False, indent=2)
+            mimetype = "application/json"
+            extension = ".json"
+        elif export_format == "txt" and payload.get("format") == "text":
+            content = payload.get("content", "")
+            mimetype = "text/plain; charset=utf-8"
+            extension = ".txt"
+        elif export_format == "csv" and payload.get("format") == "csv":
+            output = io.StringIO(newline="")
+            writer = csv.DictWriter(
+                output, fieldnames=payload.get("columns", []),
+                extrasaction="ignore")
+            writer.writeheader()
+            writer.writerows(payload.get("rows", []))
+            content = output.getvalue()
+            mimetype = "text/csv; charset=utf-8"
+            extension = ".csv"
+        else:
+            return jsonify({"error": "unsupported export format"}), 406
+
+        download_name = (filename if filename.lower().endswith(extension)
+                         else f"{filename}{extension}")
+        response = Response(content, mimetype=mimetype)
+        response.headers["Content-Disposition"] = (
+            f'attachment; filename="{download_name}"')
+        return response
+
     @app.get("/api/reports/<source>")
     def list_reports(source):
         base = report_sources.get(source)