/**
 * @file EditorModal.tsx
 * @description Create/edit modal for text-file config artifacts (skills,
 * agents, commands, output styles, memory). Tool-agnostic: it takes a
 * `fetchContent` callback instead of reaching for any particular tool's API,
 * so the same modal serves both the Claude Code and Codex config pages. It
 * loads a file ONCE per path (never over the user's typing), refuses to save
 * over a failed or truncated read, asks before discarding edits or overwriting
 * a file changed on disk, and is a real dialog (focus trap, Escape).
 * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
 */

import { useCallback, useEffect, useRef, useState } from "react";
import { useTranslation } from "react-i18next";
import { Pencil, X, Save, AlertCircle } from "lucide-react";
import type { CcArtifactType } from "../../lib/api";
import { confirmDialog, confirmDiscard } from "../../lib/confirm";
import { useDialog } from "../../hooks/useDialog";
import { useUnsavedGuard } from "../../hooks/useUnsavedGuard";

/** What a fetcher may answer: the text, or the API's `{text, truncated}`. */
type Fetched = string | { text: string; truncated?: boolean };
const textOf = (r: Fetched) => (typeof r === "string" ? r : r.text);

/** Same rule the server applies to an artifact name. */
const NAME_RE = /^[A-Za-z0-9][A-Za-z0-9._-]{0,63}$/;

/** Claude Code's own scope union, kept as the default so existing callers
 *  (CcConfig.tsx) don't need to name it. Codex has no `auto-memory` scope —
 *  its caller instantiates `TScope` as just `"user" | "project"` instead of
 *  casting its own narrower type into this one. */
type DefaultScope = "user" | "project" | "auto-memory";

export type EditorState<
  TType extends string = CcArtifactType,
  TScope extends string = DefaultScope,
> =
  | {
      mode: "create";
      type: TType;
      defaultScope: "user" | "project";
      template: string;
      project?: string; // set for type === "auto-memory"
    }
  | {
      mode: "edit";
      type: TType;
      scope: TScope;
      name: string;
      filePath: string;
      project?: string; // set for type === "auto-memory"
    }
  | null;

/** Types that are a single fixed file per scope (e.g. Claude's CLAUDE.md, Codex's
 *  AGENTS.md / config.toml) - no `name` field, and no artifact name is ever sent. */
const DEFAULT_NAMELESS_TYPES = ["memory"];

interface EditorModalProps<
  TType extends string = CcArtifactType,
  TScope extends string = DefaultScope,
> {
  state: NonNullable<EditorState<TType, TScope>>;
  fetchContent: (filePath: string) => Promise<Fetched>;
  onClose: () => void;
  onSave: (args: {
    type: TType;
    targetScope: TScope;
    name: string | undefined;
    content: string;
    project?: string;
  }) => Promise<void>;
  /** Which `state.type` values are nameless singleton files. Defaults to
   *  Claude Code's own `["memory"]` so existing callers are unaffected. */
  namelessTypes?: readonly string[];
  /** Refuse the Project target (its folder is the plugin cache, wiped on update). */
  projectDisabled?: boolean;
}

export function EditorModal<
  TType extends string = CcArtifactType,
  TScope extends string = DefaultScope,
>({
  state,
  fetchContent,
  onClose,
  onSave,
  namelessTypes = DEFAULT_NAMELESS_TYPES,
  projectDisabled = false,
}: EditorModalProps<TType, TScope>) {
  const { t } = useTranslation("ccConfig");
  const isCreate = state.mode === "create";
  const isNameless = namelessTypes.includes(state.type);
  const isAutoMemory = state.type === "auto-memory";
  const [content, setContent] = useState<string>(isCreate ? state.template : "");
  const [name, setName] = useState<string>("");
  const [targetScope, setTargetScope] = useState<"user" | "project">(
    isCreate
      ? state.defaultScope
      : state.scope === "auto-memory"
        ? "user"
        : (state.scope as "user" | "project")
  );
  const [loading, setLoading] = useState(!isCreate);
  const [saving, setSaving] = useState(false);
  const [error, setError] = useState<string | null>(null);
  // "ok" once an edit's text is in; a failed or truncated load never saves —
  // Save over a failed load wrote an EMPTY file, over a truncated one a cut file.
  const [loadState, setLoadState] = useState<"ok" | "failed" | "truncated">(
    isCreate ? "ok" : "failed"
  );
  // The text as opened; `dirty` and the changed-on-disk check compare to it.
  const original = useRef<string>(isCreate ? state.template : "");
  const panelRef = useRef<HTMLDivElement>(null);
  const titleId = "cc-editor-title";
  const dirty = !loading && content !== original.current;
  useUnsavedGuard(dirty);

  // Read through a ref: callers pass an inline fetcher, and a dependency on it
  // reloaded the file on every parent render — overwriting the user's typing.
  const fetchRef = useRef(fetchContent);
  fetchRef.current = fetchContent;
  const editPath = state.mode === "edit" ? state.filePath : null;

  // `t` through a ref too: a language switch must not re-run the load below.
  const tRef = useRef(t);
  tRef.current = t;

  // For edit mode, fetch the file once per path.
  useEffect(() => {
    if (editPath === null) return;
    let live = true;
    setLoading(true);
    fetchRef
      .current(editPath)
      .then((r) => {
        if (!live) return;
        const text = textOf(r);
        original.current = text;
        setContent(text);
        const cut = typeof r !== "string" && !!r.truncated;
        setLoadState(cut ? "truncated" : "ok");
        if (cut) setError(tRef.current("edit.truncatedReadOnly"));
        setLoading(false);
      })
      .catch((err: unknown) => {
        if (!live) return;
        const msg = err instanceof Error ? err.message : "unknown";
        setLoadState("failed");
        setError(tRef.current("edit.loadError", { message: msg }));
        setLoading(false);
      });
    return () => {
      live = false;
    };
  }, [editPath]);

  const requestClose = useCallback(async () => {
    if (dirty && !(await confirmDiscard())) return;
    onClose();
  }, [dirty, onClose]);

  // Escape closes — but not while typing in the textarea, where it only leaves
  // the field (an editor's Escape must never cost a draft).
  useDialog(true, panelRef, () => {
    const el = document.activeElement;
    if (el instanceof HTMLTextAreaElement) {
      el.blur();
      return;
    }
    void requestClose();
  });

  const handleSave = useCallback(async () => {
    setSaving(true);
    setError(null);
    try {
      if (!isNameless && state.mode === "create") {
        if (!name.trim()) {
          setError(t("edit.nameRequired"));
          return;
        }
        if (!isAutoMemory && !NAME_RE.test(name)) {
          setError(t("edit.nameInvalid"));
          return;
        }
      }
      // The file changed on disk since it was opened (a running session, a
      // terminal): say so instead of silently overwriting that change.
      if (state.mode === "edit") {
        const fresh = await fetchRef
          .current(state.filePath)
          .then(textOf)
          .catch(() => null);
        // Could not re-read it: say so rather than saving blind.
        const ask =
          fresh === null
            ? {
                title: t("edit.unverifiedTitle"),
                message: t("edit.unverifiedBody"),
                confirmLabel: t("edit.saveAnyway"),
              }
            : fresh !== original.current
              ? {
                  title: t("edit.changedOnDiskTitle"),
                  message: t("edit.changedOnDiskBody"),
                  confirmLabel: t("edit.overwrite"),
                }
              : null;
        if (ask && !(await confirmDialog(ask))) return;
      }
      // For auto-memory creates, append a .md extension when the user omits it.
      const createName = isAutoMemory && !/\.md$/i.test(name) ? `${name}.md` : name;
      const effectiveName =
        state.mode === "edit" ? state.name : isNameless ? undefined : createName;
      await onSave({
        type: state.type,
        // Widening back to TScope: this component is the one place that
        // legitimately knows about all three scope shapes across both
        // callers; a Codex caller's TScope ("user" | "project") never
        // actually receives "auto-memory" since isAutoMemory can only be
        // true when TType includes "auto-memory" (Claude-only).
        targetScope: (isAutoMemory ? "auto-memory" : targetScope) as TScope,
        name: effectiveName,
        content,
        project: state.project,
      });
      original.current = content;
    } catch (err: unknown) {
      const msg = err instanceof Error ? err.message : "unknown";
      setError(t("edit.writeError", { message: msg }));
    } finally {
      setSaving(false);
    }
  }, [state, targetScope, name, content, isAutoMemory, isNameless, onSave, t]);

  const titleText = isCreate
    ? isAutoMemory
      ? t("memory.newFileTitle", { project: state.project ?? "" })
      : t("edit.newTitle", { type: state.type })
    : t("edit.editTitle", { name: state.mode === "edit" ? state.name : "" });

  return (
    <div
      className="fixed inset-0 bg-surface-0/70 z-50 flex items-center justify-center p-4"
      onClick={() => void requestClose()}
    >
      <div
        ref={panelRef}
        role="dialog"
        aria-modal="true"
        aria-labelledby={titleId}
        className="relative w-full max-w-4xl max-h-[90vh] rounded-xl border border-border bg-surface-1 flex flex-col"
        onClick={(e) => e.stopPropagation()}
      >
        <div className="flex items-center gap-2 border-b border-border px-4 py-2.5">
          <Pencil className="w-4 h-4 text-fg-muted" />
          <span id={titleId} className="text-sm font-medium text-fg-primary flex-1 truncate">
            {titleText}
          </span>
          <button
            type="button"
            onClick={() => void requestClose()}
            className="text-fg-secondary hover:text-fg-primary p-1 rounded-md hover:bg-surface-3"
            aria-label={t("common.close")}
          >
            <X className="w-4 h-4" />
          </button>
        </div>

        <div className="overflow-auto p-4 space-y-3">
          {isCreate && !isNameless && (
            <div className="grid grid-cols-1 md:grid-cols-2 gap-3">
              <div>
                <label className="block text-[11px] font-semibold uppercase tracking-wider text-fg-muted mb-1">
                  {t("edit.nameLabel")}
                </label>
                <input
                  value={name}
                  onChange={(e) => setName(e.target.value)}
                  placeholder={
                    isAutoMemory ? t("memory.namePlaceholder") : t("edit.namePlaceholder")
                  }
                  pattern={isAutoMemory ? undefined : "[A-Za-z0-9][A-Za-z0-9._-]{0,63}"}
                  className="w-full bg-surface-2 border border-border rounded-md px-3 py-1.5 text-sm font-mono text-fg-primary placeholder:text-fg-muted focus:outline-none focus:border-accent/50"
                />
                <p className="mt-1 text-[10px] text-fg-muted">
                  {isAutoMemory ? t("memory.nameHelp") : t("edit.nameHelp")}
                </p>
              </div>
              {isAutoMemory ? (
                <div>
                  <label className="block text-[11px] font-semibold uppercase tracking-wider text-fg-muted mb-1">
                    {t("memory.projectLabel")}
                  </label>
                  <div className="rounded-md border border-border bg-surface-2 px-3 py-1.5 font-mono text-[11px] text-fg-secondary truncate">
                    {state.project}
                  </div>
                  <p className="mt-1 text-[10px] text-fg-muted">{t("memory.projectHelp")}</p>
                </div>
              ) : (
                <div>
                  <label className="block text-[11px] font-semibold uppercase tracking-wider text-fg-muted mb-1">
                    {t("edit.scopePicker")}
                  </label>
                  <div className="inline-flex rounded-md border border-border bg-surface-2 p-0.5">
                    {(["user", "project"] as const).map((s) => (
                      <button
                        key={s}
                        type="button"
                        aria-pressed={targetScope === s}
                        disabled={s === "project" && projectDisabled}
                        title={
                          s === "project" && projectDisabled ? t("scope.projectInCache") : undefined
                        }
                        onClick={() => setTargetScope(s)}
                        className={`px-3 py-1 text-[11px] font-medium rounded disabled:opacity-40 disabled:cursor-not-allowed ${
                          targetScope === s
                            ? "bg-accent/20 text-accent border border-accent/30"
                            : "text-fg-secondary hover:text-fg-primary"
                        }`}
                      >
                        {t(`scope.${s}`)}
                      </button>
                    ))}
                  </div>
                </div>
              )}
            </div>
          )}

          <div>
            <label className="block text-[11px] font-semibold uppercase tracking-wider text-fg-muted mb-1">
              {t("edit.contentLabel")}
            </label>
            {loading ? (
              <div className="h-72 rounded-md border border-border bg-surface-2 animate-pulse" />
            ) : (
              <textarea
                value={content}
                onChange={(e) => setContent(e.target.value)}
                readOnly={loadState !== "ok"}
                aria-label={t("edit.contentLabel")}
                spellCheck={false}
                className="w-full h-72 bg-surface-2 border border-border rounded-md px-3 py-2 text-[11px] font-mono text-fg-primary placeholder:text-fg-muted focus:outline-none focus:border-accent/50 resize-y"
              />
            )}
          </div>

          {error && (
            <div
              role="alert"
              className="rounded-md border border-status-danger/40 bg-status-danger/10 px-3 py-2 text-xs text-status-danger inline-flex items-center gap-2"
            >
              <AlertCircle className="w-3.5 h-3.5" />
              {error}
            </div>
          )}
        </div>

        <div className="border-t border-border px-4 py-3 flex items-center justify-end gap-2">
          <button
            type="button"
            onClick={() => void requestClose()}
            className="text-[12px] font-medium px-3 py-1.5 rounded-md border border-border bg-surface-2 hover:bg-surface-3 text-fg-secondary"
          >
            {t("edit.cancel")}
          </button>
          <button
            type="button"
            onClick={handleSave}
            disabled={saving || loading || loadState !== "ok"}
            className="text-[12px] font-medium px-3 py-1.5 rounded-md border border-accent/40 bg-accent/15 hover:bg-accent/25 text-accent inline-flex items-center gap-1.5 disabled:opacity-60"
          >
            <Save className="w-3.5 h-3.5" />
            {saving ? t("edit.saving") : t("edit.save")}
          </button>
        </div>
      </div>
    </div>
  );
}