import { t } from "@lingui/core/macro";
import { Trans, useLingui } from "@lingui/react/macro";
import type { ProjectGoal, ProjectGoalStatus, ProjectSession } from "@rakazo/contracts";
import { useCallback, useEffect, useState } from "react";
import { rpc } from "../lib/rpc";

const INITIAL_VISIBLE = 4;

function goalStatusTone(status: ProjectGoalStatus): string {
  if (status === "done") return "text-success";
  if (status === "doing") return "text-warning";
  return "text-foreground";
}

function goalStatusLabel(status: ProjectGoalStatus): string {
  switch (status) {
    case "open":
      return t`To do`;
    case "doing":
      return t`In progress`;
    case "done":
      return t`Done`;
    default: {
      const _exhaustive: never = status;
      return _exhaustive;
    }
  }
}

function sessionStatusTone(status: ProjectSession["status"]): string {
  if (status === "failed") return "text-destructive";
  if (status === "cancelled") return "text-muted-foreground";
  if (status === "completed") return "text-success";
  if (status === "waiting_input" || status === "waiting_takeover") return "text-warning";
  return "text-foreground";
}

function sessionStatusLabel(status: ProjectSession["status"]): string {
  switch (status) {
    case "queued":
      return t`Queued`;
    case "leased":
    case "running":
      return t`Running`;
    case "waiting_input":
      return t`Waiting`;
    case "waiting_takeover":
      return t`Takeover`;
    case "completed":
      return t`Done`;
    case "failed":
      return t`Failed`;
    case "cancelled":
      return t`Cancelled`;
    default: {
      const _exhaustive: never = status;
      return _exhaustive;
    }
  }
}

function formatRelativeTime(iso: string): string {
  const delta = Date.now() - new Date(iso).getTime();
  const minutes = Math.round(delta / 60_000);
  if (minutes < 1) return t`just now`;
  if (minutes < 60) return t`${minutes}m ago`;
  const hours = Math.round(minutes / 60);
  if (hours < 24) return t`${hours}h ago`;
  const days = Math.round(hours / 24);
  return t`${days}d ago`;
}

type ProjectSessionTimelineProps = {
  sectionId: string;
  sectionName: string;
  groupId: string;
  groupName: string;
  onOpenSession: (sourceMessageId: string) => void;
  onStartSession: () => void;
  onOpenGroupChat: (groupId: string) => void;
  onStartVoiceFirst: (groupId: string) => void;
};

export function ProjectSessionTimeline({
  sectionId,
  sectionName,
  groupId,
  groupName,
  onOpenSession,
  onStartSession,
  onOpenGroupChat,
  onStartVoiceFirst,
}: ProjectSessionTimelineProps) {
  const { t } = useLingui();
  const [goals, setGoals] = useState<ProjectGoal[]>([]);
  const [sessions, setSessions] = useState<ProjectSession[]>([]);
  const [loadingGoals, setLoadingGoals] = useState(true);
  const [loadingSessions, setLoadingSessions] = useState(true);
  const [sessionsExpanded, setSessionsExpanded] = useState(false);
  const [creatingGoal, setCreatingGoal] = useState(false);
  const [newGoalTitle, setNewGoalTitle] = useState("");

  const reloadGoals = useCallback(async () => {
    const result = await rpc.projectGoals.list({
      sectionId,
      groupId,
      seedDefaults: true,
    });
    setGoals(result);
  }, [groupId, sectionId]);

  useEffect(() => {
    let cancelled = false;
    void reloadGoals()
      .catch(() => {
        if (!cancelled) setGoals([]);
      })
      .finally(() => {
        if (!cancelled) setLoadingGoals(false);
      });
    return () => {
      cancelled = true;
    };
  }, [reloadGoals]);

  useEffect(() => {
    let cancelled = false;
    void rpc.groups
      .listSessions({ groupId })
      .then((result) => {
        if (!cancelled) setSessions(result.sessions);
      })
      .catch(() => {
        if (!cancelled) setSessions([]);
      })
      .finally(() => {
        if (!cancelled) setLoadingSessions(false);
      });
    return () => {
      cancelled = true;
    };
  }, [groupId]);

  const visibleSessions = sessionsExpanded ? sessions : sessions.slice(0, INITIAL_VISIBLE);
  const hiddenSessionCount = Math.max(0, sessions.length - INITIAL_VISIBLE);

  const handleCreateGoal = async () => {
    const title = newGoalTitle.trim();
    if (!title) return;
    setCreatingGoal(true);
    try {
      await rpc.projectGoals.create({
        sectionId,
        title,
        groupId,
      });
      setNewGoalTitle("");
      await reloadGoals();
    } finally {
      setCreatingGoal(false);
    }
  };

  return (
    <div className="flex flex-1 flex-col overflow-hidden">
      <div className="border-b border-border/60 px-4 py-4 md:px-8 md:py-5 lg:px-10">
        <p className="text-ui-label font-medium uppercase tracking-wide text-muted-foreground">
          <Trans>Project</Trans>
        </p>
        <h2 className="text-ui-body font-semibold tracking-tight text-foreground">{sectionName}</h2>
        <p className="mt-1 text-ui-body-sm text-muted-foreground">
          <Trans>
            Goals for this project, separate from chat messages. Conversations are below.
          </Trans>
        </p>
      </div>

      <div className="flex-1 overflow-y-auto px-4 py-4 md:px-8 lg:px-10">
        <div className="mx-auto flex w-full max-w-2xl flex-col gap-8">
          <section aria-labelledby="project-goals-heading">
            <div className="mb-3 flex items-center justify-between gap-3">
              <h3
                id="project-goals-heading"
                className="text-ui-body-sm font-semibold text-foreground"
              >
                <Trans>Goals</Trans>
              </h3>
              <span className="rounded-full border border-primary/25 bg-primary/10 px-2 py-0.5 text-ui-label font-medium text-primary">
                <Trans>Goal</Trans>
              </span>
            </div>

            {loadingGoals ? (
              <p className="text-ui-body-sm text-muted-foreground">
                <Trans>Loading goals…</Trans>
              </p>
            ) : goals.length === 0 ? (
              <div className="rounded-[16px] border border-dashed border-border/70 bg-card/40 px-4 py-6 text-center">
                <p className="text-ui-body-sm text-muted-foreground">
                  <Trans>No goals in this project yet.</Trans>
                </p>
              </div>
            ) : (
              <div className="flex flex-col gap-2">
                {goals.map((goal) => {
                  const tone = goalStatusTone(goal.status);
                  const label = goalStatusLabel(goal.status);
                  const linkedGroupId = goal.groupId ?? groupId;
                  return (
                    <article
                      key={goal.id}
                      data-testid="project-goal-row"
                      className="rounded-[16px] border border-primary/20 bg-card/80 px-4 py-3.5 shadow-xs"
                    >
                      <div className="flex items-start justify-between gap-3">
                        <div className="min-w-0 flex-1">
                          <div className="flex flex-wrap items-center gap-2">
                            <span className="rounded-full border border-primary/30 bg-primary/10 px-2 py-0.5 text-ui-label font-semibold uppercase tracking-wide text-primary">
                              <Trans>Goal</Trans>
                            </span>
                            <p className="truncate text-ui-body font-medium text-foreground">
                              {goal.title}
                            </p>
                          </div>
                          {goal.description ? (
                            <p className="mt-1.5 line-clamp-2 text-ui-body-sm text-muted-foreground">
                              {goal.description}
                            </p>
                          ) : null}
                        </div>
                        <div className="flex shrink-0 flex-col items-end gap-1">
                          <span className="text-ui-label text-muted-foreground">
                            {formatRelativeTime(goal.updatedAt)}
                          </span>
                          <span
                            className={`flex items-center gap-1 text-ui-label font-medium ${tone}`}
                          >
                            <span
                              className="h-1.5 w-1.5 rounded-full bg-current"
                              aria-hidden="true"
                            />
                            {label}
                          </span>
                        </div>
                      </div>
                      <div className="mt-3 flex flex-wrap gap-2">
                        {/voice\s*first/i.test(goal.title) ? (
                          <button
                            type="button"
                            data-testid="voice-first-start"
                            onClick={() => onStartVoiceFirst(linkedGroupId)}
                            className="rounded-lg border border-emerald-500/40 bg-emerald-500/15 px-3 py-1.5 text-ui-label font-semibold text-emerald-200 transition-colors hover:bg-emerald-500/25"
                          >
                            <Trans>Start Voice First</Trans>
                          </button>
                        ) : null}
                        <button
                          type="button"
                          onClick={() => onOpenGroupChat(linkedGroupId)}
                          className="rounded-lg border border-border bg-background px-3 py-1.5 text-ui-label font-medium text-foreground transition-colors hover:bg-accent"
                        >
                          <Trans>Open conversation</Trans>
                        </button>
                      </div>
                    </article>
                  );
                })}
              </div>
            )}

            <div className="mt-4 flex flex-col gap-2 sm:flex-row">
              <input
                type="text"
                value={newGoalTitle}
                onChange={(event) => setNewGoalTitle(event.target.value)}
                placeholder={t`New goal…`}
                className="min-w-0 flex-1 rounded-xl border border-border bg-background px-3 py-2 text-ui-body-sm text-foreground"
                onKeyDown={(event) => {
                  if (event.key === "Enter") void handleCreateGoal();
                }}
              />
              <button
                type="button"
                disabled={creatingGoal || !newGoalTitle.trim()}
                onClick={() => void handleCreateGoal()}
                className="rounded-xl border border-border bg-background px-4 py-2 text-ui-body-sm font-medium text-foreground transition-colors hover:bg-accent disabled:opacity-50"
              >
                <Trans>Add goal</Trans>
              </button>
            </div>
          </section>

          <section aria-labelledby="project-chats-heading">
            <div className="mb-3 flex items-center justify-between gap-3">
              <h3
                id="project-chats-heading"
                className="text-ui-body-sm font-semibold text-foreground"
              >
                <Trans>Conversations</Trans>
              </h3>
              <span className="text-ui-label text-muted-foreground">{groupName}</span>
            </div>

            {loadingSessions ? (
              <p className="text-ui-body-sm text-muted-foreground">
                <Trans>Loading conversations…</Trans>
              </p>
            ) : sessions.length === 0 ? (
              <div className="rounded-[16px] border border-border/70 bg-card/50 px-4 py-6 text-center">
                <p className="text-ui-body-sm text-muted-foreground">
                  <Trans>No conversations in this project chat yet.</Trans>
                </p>
                <button
                  type="button"
                  onClick={onStartSession}
                  className="mt-4 rounded-xl border border-border bg-background px-4 py-2 text-ui-body-sm font-medium text-foreground transition-colors hover:bg-accent"
                >
                  <Trans>Start chat</Trans>
                </button>
              </div>
            ) : (
              <div className="flex flex-col gap-2">
                {visibleSessions.map((session) => {
                  const tone = sessionStatusTone(session.status);
                  const label = sessionStatusLabel(session.status);
                  const participants =
                    session.botNames.length > 0 ? session.botNames.join(", ") : t`Team`;
                  return (
                    <button
                      key={session.sessionId}
                      type="button"
                      data-testid="project-session-row"
                      aria-label={t`${session.promptSnippet}, ${label}`}
                      onClick={() => onOpenSession(session.sourceMessageId)}
                      className="rounded-[14px] border border-border/60 bg-muted/20 px-4 py-3 text-left transition-all hover:border-border hover:bg-muted/35"
                    >
                      <div className="flex items-start justify-between gap-3">
                        <div className="min-w-0 flex-1">
                          <p className="text-ui-label font-medium uppercase tracking-wide text-muted-foreground">
                            <Trans>Chat</Trans>
                          </p>
                          <p className="truncate text-ui-body-sm font-medium text-foreground">
                            {session.promptSnippet}
                          </p>
                          <p className="mt-0.5 truncate text-ui-label text-muted-foreground">
                            {participants}
                          </p>
                        </div>
                        <div className="flex shrink-0 flex-col items-end gap-1">
                          <span className="text-ui-label text-muted-foreground">
                            {formatRelativeTime(session.startedAt)}
                          </span>
                          <span
                            className={`flex items-center gap-1 text-ui-label font-medium ${tone}`}
                          >
                            <span
                              className="h-1.5 w-1.5 rounded-full bg-current"
                              aria-hidden="true"
                            />
                            {label}
                          </span>
                        </div>
                      </div>
                    </button>
                  );
                })}
                {!sessionsExpanded && hiddenSessionCount > 0 ? (
                  <button
                    type="button"
                    onClick={() => setSessionsExpanded(true)}
                    className="self-start px-1 py-1 text-ui-body-sm font-medium text-primary hover:underline"
                  >
                    <Trans>More conversations ({hiddenSessionCount})</Trans>
                  </button>
                ) : null}
                <button
                  type="button"
                  onClick={onStartSession}
                  className="mt-1 self-start rounded-lg border border-border/70 px-3 py-1.5 text-ui-label font-medium text-foreground transition-colors hover:bg-accent"
                >
                  <Trans>New conversation</Trans>
                </button>
              </div>
            )}
          </section>
        </div>
      </div>
    </div>
  );
}