package httpapi

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

	"github.com/dtoro/oikos/internal/execlog"
	"github.com/go-chi/chi/v5"
	"github.com/google/uuid"
)

// serveExecutionLogs returns an execution's streamed command output.
//
// Registered as a carve-out rather than through the OpenAPI codegen for the
// same reason as /activity/recent: it is a recency-ordered projection with no
// schema type yet. Without this the execution_logs rows would be write-only —
// which is the exact shape of the bugs this whole change set has been about.
func (s *Server) serveExecutionLogs(w http.ResponseWriter, req *http.Request) {
	ctx := req.Context()

	rawID := chi.URLParam(req, "id")
	execID, err := uuid.Parse(rawID)
	if err != nil {
		writeProblem(w, req, http.StatusBadRequest, "invalid execution id", rawID)
		return
	}

	limit := 1000
	if l := req.URL.Query().Get("limit"); l != "" {
		if n, perr := strconv.Atoi(l); perr == nil && n > 0 && n <= 5000 {
			limit = n
		}
	}

	chunks, err := execlog.Read(ctx, s.pool, execID, limit)
	if err != nil {
		writeProblem(w, req, http.StatusInternalServerError, "query failed", err.Error())
		return
	}

	// Also hand back the concatenation, since that is what a caller tailing
	// output actually wants to render.
	var combined strings.Builder
	for _, c := range chunks {
		combined.WriteString(c.Chunk)
	}

	w.Header().Set("Content-Type", "application/json")
	_ = json.NewEncoder(w).Encode(map[string]any{
		"items":    chunks,
		"combined": combined.String(),
	})
}