import type {
  MediaAsset,
  MediaCapabilities,
  MediaCollection,
  MediaEditPlan,
  MediaProject,
  MediaRender,
  PlatformProfileSummary,
} from "@rakazo/contracts";
import { Stack, useLocalSearchParams } from "expo-router";
import { useVideoPlayer, VideoView } from "expo-video";
import { useCallback, useEffect, useRef, useState } from "react";
import {
  ActivityIndicator,
  Alert,
  Pressable,
  ScrollView,
  StyleSheet,
  Text,
  View,
} from "react-native";
import { mobileTokens } from "../lib/appearance";
import { useI18n } from "../lib/i18n";
import {
  mediaRpc,
  registerDeviceSource,
  renderVideoSource,
  shareRender,
  uploadAssets,
} from "../lib/media-api";
import type { MediaVariant } from "../lib/media-project";
import {
  blockers,
  canApprove,
  canShare,
  MEDIA_POLL_MS,
  projectReadiness,
  projectVariants,
  shouldPollProject,
  variantState,
  videoOutput,
} from "../lib/media-project";
import { native, useThemedStyles } from "../lib/native";

type ProjectData = { project: MediaProject; plans: MediaEditPlan[]; renders: MediaRender[] };

function message(reason: unknown): string {
  return reason instanceof Error ? reason.message : String(reason);
}

export default function MediaProjectScreen() {
  const styles = useThemedStyles(createStyles);
  const { t } = useI18n();
  const { projectId, upload } = useLocalSearchParams<{ projectId: string; upload?: string }>();
  const [data, setData] = useState<ProjectData | null>(null);
  const [assets, setAssets] = useState<MediaAsset[]>([]);
  const [profiles, setProfiles] = useState<PlatformProfileSummary[]>([]);
  const [analysis, setAnalysis] = useState(true);
  const [deviceSourceId, setDeviceSourceId] = useState<string | null>(null);
  const [uploadProgress, setUploadProgress] = useState<number | null>(null);
  const [busy, setBusy] = useState<string | null>(null);
  const [error, setError] = useState<string | null>(null);
  const uploadStarted = useRef(false);
  const planned = useRef(false);
  const uploadAbort = useRef<AbortController | null>(null);

  const load = useCallback(async () => {
    if (!projectId) return;
    const next = await mediaRpc<ProjectData>("projects/get", { projectId });
    const collections = await Promise.all(
      next.project.collectionIds.map((collectionId) =>
        mediaRpc<{ collection: MediaCollection; assets: MediaAsset[] }>("collections/get", {
          collectionId,
        }),
      ),
    );
    const byId = new Map<string, MediaAsset>();
    for (const entry of collections) for (const asset of entry.assets) byId.set(asset.id, asset);
    setAssets([...byId.values()]);
    setData(next);
  }, [projectId]);

  useEffect(() => {
    void load().catch((reason) => setError(message(reason)));
    void mediaRpc<PlatformProfileSummary[]>("profiles/list")
      .then(setProfiles)
      .catch(() => undefined);
    void registerDeviceSource()
      .then((source) => setDeviceSourceId(source.id))
      .catch(() => undefined);
    void mediaRpc<MediaCapabilities>("capabilities")
      .then((capabilities) => setAnalysis(capabilities.configured))
      .catch(() => undefined);
    return () => uploadAbort.current?.abort();
  }, [load]);

  const readiness = projectReadiness(assets, analysis, deviceSourceId);
  const uploading = uploadProgress !== null;

  const startUpload = useCallback(async () => {
    if (!deviceSourceId) return;
    uploadStarted.current = true;
    const controller = new AbortController();
    uploadAbort.current = controller;
    setUploadProgress(0);
    try {
      const failed = await uploadAssets(
        assets,
        deviceSourceId,
        setUploadProgress,
        controller.signal,
      );
      if (failed.length > 0) {
        Alert.alert(t("{count} items could not be uploaded.", { count: failed.length }));
      }
    } catch (reason) {
      if (!controller.signal.aborted) setError(message(reason));
    } finally {
      if (!controller.signal.aborted) {
        setUploadProgress(null);
        await load().catch(() => undefined);
      }
    }
  }, [assets, deviceSourceId, load, t]);

  useEffect(() => {
    if (upload === "1" && readiness === "uploading" && !uploadStarted.current) {
      void startUpload();
    }
  }, [upload, readiness, startUpload]);

  useEffect(() => {
    if (!data || readiness !== "ready" || data.plans.length > 0 || planned.current) return;
    planned.current = true;
    void (async () => {
      try {
        const plans = await mediaRpc<MediaEditPlan[]>(
          "projects/autoPlan",
          { projectId: data.project.id },
          { timeoutMs: 120_000 },
        );
        for (const plan of plans) {
          await mediaRpc("renders/start", { planId: plan.id, quality: "draft" });
        }
        await load();
      } catch (reason) {
        setError(message(reason));
      }
    })();
  }, [data, readiness, load]);

  useEffect(() => {
    if (!data || uploading) return;
    const waiting = data.plans.length === 0 && readiness === "processing";
    if (!waiting && !shouldPollProject(data.renders)) return;
    const timer = setTimeout(() => void load().catch(() => undefined), MEDIA_POLL_MS);
    return () => clearTimeout(timer);
  }, [data, readiness, uploading, load]);

  async function act(variant: MediaVariant, action: () => Promise<unknown>) {
    setBusy(variant.profileId);
    try {
      await action();
      await load();
    } catch (reason) {
      Alert.alert(message(reason));
    } finally {
      setBusy(null);
    }
  }

  const variants = data
    ? projectVariants({
        profileIds: data.project.profileIds,
        plans: data.plans,
        renders: data.renders,
        profiles,
      })
    : [];

  return (
    <ScrollView
      style={styles.screen}
      contentContainerStyle={styles.content}
      contentInsetAdjustmentBehavior="automatic"
    >
      <Stack.Screen options={{ title: data?.project.title ?? "" }} />
      {error ? <Text style={styles.error}>{error}</Text> : null}
      {!data ? <ActivityIndicator color={native.secondaryLabel} /> : null}
      {data && readiness === "uploading" ? (
        uploading ? (
          <View style={styles.progressRow}>
            <ActivityIndicator color={native.secondaryLabel} />
            <Text style={styles.status}>
              {t("Uploading {percent}%", { percent: Math.round((uploadProgress ?? 0) * 100) })}
            </Text>
          </View>
        ) : (
          <Pressable
            accessibilityRole="button"
            style={styles.primaryButton}
            onPress={() => void startUpload()}
          >
            <Text style={styles.primaryLabel}>{t("Upload")}</Text>
          </Pressable>
        )
      ) : null}
      {data && variants.length === 0 && readiness === "processing" ? (
        <ActivityIndicator color={native.secondaryLabel} />
      ) : null}
      {variants.map((variant) => (
        <VariantCard
          key={variant.profileId}
          variant={variant}
          busy={busy === variant.profileId}
          onApprove={() =>
            void act(variant, () =>
              mediaRpc("renders/start", { planId: variant.plan.id, quality: "final" }),
            )
          }
          onShare={() =>
            void act(variant, async () => {
              if (variant.final) await shareRender(variant.final);
            })
          }
        />
      ))}
      {variants.length > 0 ? <Text style={styles.note}>{t("Edit on web or desktop.")}</Text> : null}
    </ScrollView>
  );
}

function VariantCard({
  variant,
  busy,
  onApprove,
  onShare,
}: {
  variant: MediaVariant;
  busy: boolean;
  onApprove: () => void;
  onShare: () => void;
}) {
  const styles = useThemedStyles(createStyles);
  const { t } = useI18n();
  const state = variantState(variant);
  const progress = Math.round((variant.latest?.progress ?? 0) * 100);
  const blocker = blockers(variant.latest)[0];
  const status =
    state === "rendering" || state === "approved_rendering"
      ? t("Rendering {percent}%", { percent: progress })
      : state === "blocked"
        ? (blocker?.message ?? t("Blocked"))
        : state === "failed"
          ? (variant.latest?.error ?? t("Failed"))
          : null;

  return (
    <View style={styles.card}>
      <Text style={styles.cardTitle}>{variant.profileName}</Text>
      {variant.preview ? <VariantPlayer render={variant.preview} /> : null}
      {status ? (
        <Text style={state === "blocked" || state === "failed" ? styles.blocked : styles.status}>
          {status}
        </Text>
      ) : null}
      {busy ? (
        <ActivityIndicator color={native.secondaryLabel} />
      ) : canApprove(variant) || canShare(variant) ? (
        <View style={styles.actions}>
          {canApprove(variant) ? (
            <Pressable accessibilityRole="button" style={styles.button} onPress={onApprove}>
              <Text style={styles.buttonLabel}>{t("Approve")}</Text>
            </Pressable>
          ) : null}
          {canShare(variant) ? (
            <Pressable accessibilityRole="button" style={styles.button} onPress={onShare}>
              <Text style={styles.buttonLabel}>{t("Share")}</Text>
            </Pressable>
          ) : null}
        </View>
      ) : null}
    </View>
  );
}

function VariantPlayer({ render }: { render: MediaRender }) {
  const renderId = render.id;
  const fileName = videoOutput(render)?.fileName ?? null;
  const [source, setSource] = useState<{ uri: string; headers: Record<string, string> } | null>(
    null,
  );
  useEffect(() => {
    if (!fileName) return;
    let active = true;
    void renderVideoSource(renderId, fileName).then((next) => {
      if (active) setSource(next);
    });
    return () => {
      active = false;
    };
  }, [renderId, fileName]);
  return source ? <Player key={source.uri} source={source} /> : null;
}

function Player({ source }: { source: { uri: string; headers: Record<string, string> } }) {
  const styles = useThemedStyles(createStyles);
  const player = useVideoPlayer(source);
  return <VideoView player={player} nativeControls contentFit="contain" style={styles.video} />;
}

function createStyles() {
  const tokens = mobileTokens();
  return StyleSheet.create({
    screen: { flex: 1, backgroundColor: native.page },
    content: { padding: 16, gap: 12 },
    card: { padding: 14, borderRadius: 16, backgroundColor: native.fill, gap: 10 },
    cardTitle: { color: native.label, fontSize: 16, fontWeight: "600" },
    video: { width: "100%", aspectRatio: 9 / 16, maxHeight: 460, borderRadius: 12 },
    status: { color: native.secondaryLabel, fontSize: 14 },
    blocked: { color: tokens.destructive, fontSize: 14 },
    progressRow: { flexDirection: "row", alignItems: "center", gap: 10 },
    actions: { flexDirection: "row", gap: 8 },
    button: {
      minHeight: 42,
      paddingHorizontal: 16,
      borderRadius: 12,
      backgroundColor: native.fillPressed,
      alignItems: "center",
      justifyContent: "center",
    },
    buttonLabel: { color: native.label, fontSize: 15, fontWeight: "600" },
    primaryButton: {
      minHeight: 48,
      borderRadius: 12,
      backgroundColor: tokens.primary,
      alignItems: "center",
      justifyContent: "center",
    },
    primaryLabel: { color: tokens.primaryForeground, fontSize: 16, fontWeight: "600" },
    error: { color: tokens.destructive, fontSize: 14 },
    note: { color: native.tertiaryLabel, fontSize: 13, textAlign: "center", marginTop: 4 },
  });
}