import { ChevronDown, Plus } from "lucide-react";
import * as React from "react";

import { TemplateFormDialog } from "@/features/settings/ui/ChannelTemplatesSettingsCard";
import { cn } from "@/shared/lib/cn";
import { Button } from "@/shared/ui/button";
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuRadioGroup,
  DropdownMenuRadioItem,
  DropdownMenuSeparator,
  DropdownMenuTrigger,
} from "@/shared/ui/dropdown-menu";
import { Input } from "@/shared/ui/input";
import { Textarea } from "@/shared/ui/textarea";

import {
  CHANNEL_FORM_FIELD_CONTROL_CLASS,
  CHANNEL_FORM_FIELD_SHELL_CLASS,
} from "@/features/channels/ui/channelFormStyles";
import { ChannelPermissionsSettings } from "@/features/channels/ui/ChannelPermissionsSettings";
import { ChannelTypeSettings } from "@/features/channels/ui/ChannelTypeSettings";
import type { CreateChannelFormState } from "@/features/sidebar/lib/useCreateChannelForm";

const CREATE_LABEL_OPTIONAL_CLASS =
  "ml-1 text-xs font-normal text-muted-foreground/50";
const NO_TEMPLATE_VALUE = "__no-template__";

export const CREATE_CHANNEL_FORM_ID = "create-channel-form";

/**
 * The body of the create-channel form (name, description, visibility,
 * optional template). Rendered inside both the standalone dialog and the
 * "Add channel" browser's create mode. Wrap in a `<form>` with
 * `id={CREATE_CHANNEL_FORM_ID}` and hook up `form.handleSubmit`.
 */
export function CreateChannelFormFields({
  form,
}: {
  form: CreateChannelFormState;
}) {
  const { channelKind, kindLabel, isCreating } = form;
  const [isCreateTemplateOpen, setIsCreateTemplateOpen] = React.useState(false);
  const selectedTemplate = form.templates.find(
    (template) => template.id === form.selectedTemplateId,
  );
  const selectedTemplatePersonaCount =
    selectedTemplate?.agents.personas.length ?? 0;
  const selectedTemplateTeamCount = selectedTemplate?.agents.teams.length ?? 0;
  const selectedTemplateSummary = selectedTemplate
    ? [
        form.visibility === "private" ? "Private" : "Open",
        selectedTemplate.canvasTemplate ? "Canvas included" : null,
        selectedTemplatePersonaCount > 0
          ? `${selectedTemplatePersonaCount} ${selectedTemplatePersonaCount === 1 ? "agent" : "agents"}`
          : null,
        selectedTemplateTeamCount > 0
          ? `${selectedTemplateTeamCount} ${selectedTemplateTeamCount === 1 ? "team" : "teams"}`
          : null,
      ]
        .filter(Boolean)
        .join(" · ")
    : null;

  return (
    <div className="space-y-5">
      <div className="space-y-1.5">
        <label
          className="text-sm font-medium text-foreground"
          htmlFor="create-channel-name"
        >
          Name
        </label>
        <div
          className={cn(
            "flex min-h-11 items-center px-3",
            CHANNEL_FORM_FIELD_SHELL_CLASS,
          )}
        >
          <Input
            autoCapitalize="none"
            autoComplete="off"
            autoCorrect="off"
            className={cn(
              "h-8 px-0 py-0 leading-6",
              CHANNEL_FORM_FIELD_CONTROL_CLASS,
            )}
            data-testid="create-channel-name"
            disabled={isCreating}
            id="create-channel-name"
            onChange={(event) => form.setName(event.target.value)}
            placeholder={
              channelKind === "forum" ? "design-discussions" : "release-notes"
            }
            ref={form.nameInputRef}
            spellCheck={false}
            value={form.name}
          />
        </div>
      </div>

      <div className="space-y-1.5">
        <label
          className="text-sm font-medium text-foreground"
          htmlFor="create-channel-description"
        >
          Description
          <span className={CREATE_LABEL_OPTIONAL_CLASS}>Optional</span>
        </label>
        <div className={CHANNEL_FORM_FIELD_SHELL_CLASS}>
          <Textarea
            className={cn(
              "min-h-20 resize-none px-3 py-3 leading-5",
              CHANNEL_FORM_FIELD_CONTROL_CLASS,
            )}
            data-testid="create-channel-description"
            disabled={isCreating}
            id="create-channel-description"
            onChange={(event) => form.setDescription(event.target.value)}
            placeholder={`What this ${kindLabel} is for`}
            rows={2}
            value={form.description}
          />
        </div>
      </div>

      <ChannelTypeSettings
        disabled={isCreating}
        label="Type"
        onOpenChange={form.setTypePopoverOpen}
        onTemporaryChange={form.setEphemeral}
        onTtlSecondsChange={form.setTtlSeconds}
        open={form.typePopoverOpen}
        temporary={form.ephemeral}
        testIdPrefix="create-channel"
        ttlSeconds={form.ttlSeconds}
      />

      <ChannelPermissionsSettings
        disabled={isCreating}
        onVisibilityChange={form.setVisibility}
        testIdPrefix="create-channel"
        visibility={form.visibility}
      />

      <div
        className={cn(
          "flex min-h-12 items-center justify-between gap-4 rounded-xl border border-input bg-background px-3 py-3",
          isCreating && "opacity-50",
        )}
        data-testid="create-channel-template-container"
      >
        <span className="text-sm font-medium text-foreground">
          Template
          <span className={CREATE_LABEL_OPTIONAL_CLASS}>Optional</span>
        </span>
        <DropdownMenu modal={false}>
          <DropdownMenuTrigger asChild>
            <Button
              aria-label={`Template: ${selectedTemplate?.name ?? "None"}`}
              className="-mr-2.5 ml-auto h-9 min-w-0 max-w-[60%] justify-end px-2.5 text-right text-sm font-medium text-foreground hover:bg-muted/50"
              data-testid="create-channel-template"
              disabled={isCreating}
              id="create-channel-template"
              type="button"
              variant="ghost"
            >
              <span className="truncate text-right">
                {selectedTemplate?.name ?? "None"}
              </span>
              <ChevronDown className="size-4 shrink-0 text-muted-foreground/70" />
            </Button>
          </DropdownMenuTrigger>
          <DropdownMenuContent
            align="end"
            onCloseAutoFocus={(event) => event.preventDefault()}
            style={{
              minWidth: "var(--radix-dropdown-menu-trigger-width)",
            }}
          >
            <DropdownMenuRadioGroup
              onValueChange={(templateId) =>
                form.handleTemplateChange(
                  templateId === NO_TEMPLATE_VALUE ? "" : templateId,
                )
              }
              value={form.selectedTemplateId ?? NO_TEMPLATE_VALUE}
            >
              <DropdownMenuRadioItem value={NO_TEMPLATE_VALUE}>
                None
              </DropdownMenuRadioItem>
              {form.templates.map((template) => (
                <DropdownMenuRadioItem key={template.id} value={template.id}>
                  {template.name}
                </DropdownMenuRadioItem>
              ))}
            </DropdownMenuRadioGroup>
            <DropdownMenuSeparator />
            <DropdownMenuItem onSelect={() => setIsCreateTemplateOpen(true)}>
              <Plus className="size-4" />
              Create new channel template…
            </DropdownMenuItem>
          </DropdownMenuContent>
        </DropdownMenu>
        <TemplateFormDialog
          onCreated={form.handleTemplateCreated}
          onOpenChange={setIsCreateTemplateOpen}
          open={isCreateTemplateOpen}
          template={null}
        />
      </div>
      {selectedTemplateSummary ? (
        <p
          className="-mt-3 px-3 text-xs text-muted-foreground"
          data-testid="create-channel-template-summary"
        >
          {selectedTemplateSummary}
        </p>
      ) : null}

      {form.errorMessage ? (
        <p className="text-sm text-destructive">{form.errorMessage}</p>
      ) : null}
    </div>
  );
}

/**
 * Footer for the create-channel form. The submit button is bound to the form
 * via `form={CREATE_CHANNEL_FORM_ID}`.
 */
export function CreateChannelFormFooter({
  form,
  submitLabel,
}: {
  form: CreateChannelFormState;
  submitLabel?: string;
}) {
  const { isCreating, kindLabel } = form;

  return (
    <div className="flex w-full items-center justify-end gap-3">
      <Button
        data-testid="create-channel-submit"
        disabled={!form.canSubmit}
        form={CREATE_CHANNEL_FORM_ID}
        type="submit"
      >
        {isCreating ? "Creating..." : (submitLabel ?? `Create ${kindLabel}`)}
      </Button>
    </div>
  );
}