package api

import (
	"encoding/json"
	"net/http"
	"path/filepath"
	"strconv"
	"time"

	"github.com/will/k8s-agent-dashboard/internal/claude"
)

type BacklogResponse struct {
	Limit  int            `json:"limit"`
	Events []claude.Event `json:"events"`
}

func GetClaudeLiveBacklog(loader ClaudeLoader) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		limit := 200
		if l := r.URL.Query().Get("limit"); l != "" {
			if n, err := strconv.Atoi(l); err == nil && n > 0 {
				limit = n
				if limit > 1000 {
					limit = 1000
				}
			}
		}

		historyPath := filepath.Join(loader.ClaudeDir(), "history.jsonl")
		lines, err := claude.TailLastNLines(historyPath, limit)
		if err != nil {
			respondError(w, http.StatusInternalServerError, err.Error())
			return
		}

		events := make([]claude.Event, 0, len(lines))
		for _, line := range lines {
			ev := parseHistoryLine(line)
			events = append(events, ev)
		}

		respondJSON(w, http.StatusOK, BacklogResponse{
			Limit:  limit,
			Events: events,
		})
	}
}

func parseHistoryLine(line string) claude.Event {
	data := map[string]any{
		"rawLine": line,
	}

	var jsonData map[string]any
	if err := json.Unmarshal([]byte(line), &jsonData); err != nil {
		data["parseError"] = err.Error()
	} else {
		data["json"] = jsonData

		summary := map[string]string{}
		if v, ok := jsonData["sessionId"].(string); ok {
			summary["sessionId"] = v
		}
		if v, ok := jsonData["project"].(string); ok {
			summary["project"] = v
		}
		if v, ok := jsonData["display"].(string); ok {
			summary["display"] = v
		}
		data["summary"] = summary
	}

	return claude.Event{
		TS:   time.Now(),
		Type: claude.EventTypeHistoryAppend,
		Data: data,
	}
}