import { html, nothing, type TemplateResult } from 'lit';
import type { SummaryPanelConfig, SummaryPanelSource } from './types';
import {
  type SummaryDraftProblem, type SummaryPanelLocalPreferences,
  moveSummaryItem, newSummaryBlock, newSummaryValue,
  normalizeSummaryDraft, sameSummaryPanel,
} from './summary-panel';
import type { SummaryPanelDialogState } from './summary-panel-runtime-loaded';
import type { SummaryPanelHost } from './summary-panel-host';

export type SummaryPanelEditorContext = {
  host: SummaryPanelHost;
  dialog: SummaryPanelDialogState;
  local: SummaryPanelLocalPreferences;
  storageUnavailable: boolean;
  problems: SummaryDraftProblem[];
  setDialog(dialog: SummaryPanelDialogState | null): void;
  saveLocal(patch: Partial<SummaryPanelLocalPreferences>): void;
  mutate(mutate: (draft: SummaryPanelConfig) => void): void;
  deleteBlock(index: number): void;
  dragStart(event: DragEvent, token: string): void;
  drop(event: DragEvent, target: string): void;
  sourceToken(source: SummaryPanelSource): string;
  setSource(blockIndex: number, valueIndex: number, token: string): void;
  save(): void;
  reload(): void;
  close(): void;
  t(key: string): string;
};

export type SummaryPanelEditorRenderer = (
  context: SummaryPanelEditorContext,
) => TemplateResult | typeof nothing;

/** Lazy settings surface for #437; imported only after the gear is pressed. */
export const renderSummaryPanelEditor: SummaryPanelEditorRenderer = (context) => {
  const { host, dialog, local, problems, t } = context;
  const firstError = problems.find((problem) => problem.kind === 'error');
  const changed = dialog.localShow !== dialog.baseLocalShow
    || !dialog.localOnly && !sameSummaryPanel(normalizeSummaryDraft(dialog.draft), dialog.base);
  const canSave = changed && !dialog.busy && !firstError;
  const fieldProblem = (path: string) => problems.find((problem) => problem.path === path);
  const problemText = (problem: SummaryDraftProblem | undefined) => problem
    ? t(`summary.problem.${problem.code}`) : '';
  const allEntities = Object.entries(host.hass?.states || {}).sort((a, b) => {
    const an = String(a[1]?.attributes?.friendly_name || a[0]);
    const bn = String(b[1]?.attributes?.friendly_name || b[0]);
    return an.localeCompare(bn);
  });
  const query = dialog.entityFilter.trim().toLocaleLowerCase();
  const entities = query ? allEntities.filter(([id, state]) => `${id} ${
    state.attributes?.friendly_name || ''}`.toLocaleLowerCase().includes(query)) : allEntities;
  const close = () => context.close();
  const showRow = html`<label class="summary-switch"><input type="checkbox"
      .checked=${dialog.localShow}
      @change=${(event: Event) => context.setDialog({
        ...dialog, localShow: (event.target as HTMLInputElement).checked,
      })} />
    <span>${t('summary.show_local')}</span></label>`;
  const sizeRows = html`<h3 class="summary-sizes-title">${t('summary.sizes_title')}</h3>
    <div class="summary-local-sizes">
      <label>${t('kiosk.icon_scale')}</label>
      <input type="range" min="50" max="300" step="5"
        .value=${String(Math.round(local.icon_scale * 100))}
        @input=${(event: Event) => context.saveLocal({
          icon_scale: Number((event.target as HTMLInputElement).value) / 100,
        })} />
      <span>${Math.round(local.icon_scale * 100)}%</span>
      <label>${t('kiosk.font_scale')}</label>
      <input type="range" min="50" max="300" step="5"
        .value=${String(Math.round(local.font_scale * 100))}
        @input=${(event: Event) => context.saveLocal({
          font_scale: Number((event.target as HTMLInputElement).value) / 100,
        })} />
      <span>${Math.round(local.font_scale * 100)}%</span>
      <button class="btn ghost summary-size-reset" type="button"
        @click=${() => context.saveLocal({ icon_scale: 1, font_scale: 1 })}>${t('gs.reset')}</button>
    </div>
    ${context.storageUnavailable
      ? html`<div class="summary-problem warning">${t('summary.storage_unavailable')}</div>` : nothing}`;
  return html`<hp-dialog .hass=${host.hass} .title=${t('summary.settings')}
      icon="mdi:view-dashboard-outline" dismiss-on-scrim aria-busy=${String(dialog.busy)}
      @hp-close=${close}>
    <div class="body summary-editor">
      ${dialog.localOnly ? html`<p class="rhint">${t(
        dialog.localOnlyHint,
      )}</p>` : nothing}
      ${dialog.localOnly ? html`${showRow}${sizeRows}` : html`
        <label>${t('summary.panel_title')}</label>
        <input type="text" .value=${dialog.draft.title}
          data-summary-error=${String(dialog.attempted && firstError?.path === 'title')}
          aria-invalid=${fieldProblem('title')?.kind === 'error' ? 'true' : 'false'}
          @input=${(event: Event) => context.mutate((draft) => {
            draft.title = (event.target as HTMLInputElement).value;
          })} />
        ${fieldProblem('title')
          ? html`<div class="summary-problem error">${problemText(fieldProblem('title'))}</div>` : nothing}
        ${showRow}
        <label class="summary-switch"><input type="checkbox" .checked=${dialog.draft.show_on_mobile}
          @change=${(event: Event) => context.mutate((draft) => {
            draft.show_on_mobile = (event.target as HTMLInputElement).checked;
          })} />
          <span>${t('summary.show_mobile')}</span></label>
        ${sizeRows}
        <label>${t('summary.search_entities')}</label>
        <input type="search" .value=${dialog.entityFilter}
          @input=${(event: Event) => context.setDialog({
            ...dialog, entityFilter: (event.target as HTMLInputElement).value,
          })} />
        ${entities.length ? nothing : html`<div class="summary-empty">${t('summary.no_search_results')}</div>`}
        <div class="summary-editor-blocks">
          ${dialog.draft.blocks.map((block, bi) => {
            const bp = `blocks.${bi}`;
            const scopeProblem = fieldProblem(`${bp}.scope`);
            return html`<article class="summary-editor-block"
                @dragover=${(event: DragEvent) => event.preventDefault()}
                @drop=${(event: DragEvent) => context.drop(event, `block:${bi}`)}>
              <div class="summary-editor-row summary-block-head">
                <span class="summary-drag" draggable="true" title=${t('summary.drag')}
                  @dragstart=${(event: DragEvent) => context.dragStart(event, `block:${bi}`)}>⋮⋮</span>
                <input type="text" .value=${block.title}
                  placeholder=${t('summary.block_title')}
                  data-summary-error=${String(dialog.attempted && firstError?.path === `${bp}.title`)}
                  @input=${(event: Event) => context.mutate((draft) => {
                    draft.blocks[bi].title = (event.target as HTMLInputElement).value;
                  })} />
                <button type="button" title=${t('summary.up')} ?disabled=${bi === 0}
                  @click=${() => context.mutate((draft) => {
                    draft.blocks = moveSummaryItem(draft.blocks, bi, bi - 1);
                  })}>↑</button>
                <button type="button" title=${t('summary.down')}
                  ?disabled=${bi === dialog.draft.blocks.length - 1}
                  @click=${() => context.mutate((draft) => {
                    draft.blocks = moveSummaryItem(draft.blocks, bi, bi + 1);
                  })}>↓</button>
                <button type="button" title=${t('btn.delete')}
                  @click=${() => context.deleteBlock(bi)}><ha-icon icon="mdi:delete-outline"></ha-icon></button>
              </div>
              ${fieldProblem(`${bp}.title`)
                ? html`<div class="summary-problem error">${problemText(fieldProblem(`${bp}.title`))}</div>` : nothing}
              <div class="summary-editor-row">
                <label class="summary-switch"><input type="checkbox" .checked=${block.visible}
                  @change=${(event: Event) => context.mutate((draft) => {
                    draft.blocks[bi].visible = (event.target as HTMLInputElement).checked;
                  })} />
                  <span>${t('summary.block_visible')}</span></label>
                <select .value=${block.scope.type}
                  @change=${(event: Event) => context.mutate((draft) => {
                    draft.blocks[bi].scope = (event.target as HTMLSelectElement).value === 'space'
                      ? { type: 'space', space_id: host._space } : { type: 'all' };
                  })}>
                  <option value="all" ?selected=${block.scope.type === 'all'}>${t('summary.scope_all')}</option>
                  <option value="space" ?selected=${block.scope.type === 'space'}>${t('summary.scope_space')}</option>
                </select>
                ${block.scope.type === 'space' ? html`<select .value=${block.scope.space_id}
                  data-summary-error=${String(dialog.attempted && firstError?.path === `${bp}.scope`)}
                  @change=${(event: Event) => context.mutate((draft) => {
                    const scope = draft.blocks[bi].scope;
                    if (scope.type === 'space') scope.space_id = (event.target as HTMLSelectElement).value;
                  })}>
                ${!host._model.some((space) => space.id === block.scope.space_id)
                    ? html`<option value=${block.scope.space_id} selected>${block.scope.space_id}</option>` : nothing}
                ${host._model.map((space) => html`<option value=${space.id}
                    ?selected=${space.id === block.scope.space_id}>${space.title}</option>`)}
                </select>` : nothing}
              </div>
              ${scopeProblem
                ? html`<div class="summary-problem ${scopeProblem.kind}">${problemText(scopeProblem)}</div>` : nothing}
              <div class="summary-editor-values">
                ${block.values.map((value, vi) => {
                  const vp = `${bp}.values.${vi}`;
                  const sourceProblem = fieldProblem(`${vp}.source`);
                  const sourceToken = context.sourceToken(value.source);
                  return html`<div class="summary-editor-value"
                      @dragover=${(event: DragEvent) => { event.preventDefault(); event.stopPropagation(); }}
                      @drop=${(event: DragEvent) => context.drop(event, `value:${bi}:${vi}`)}>
                    <div class="summary-editor-row">
                      <span class="summary-drag" draggable="true" title=${t('summary.drag')}
                        @dragstart=${(event: DragEvent) => context.dragStart(event, `value:${bi}:${vi}`)}>⋮⋮</span>
                      <input type="text" .value=${value.label}
                        placeholder=${t('summary.value_name')}
                        data-summary-error=${String(dialog.attempted && firstError?.path === `${vp}.label`)}
                        @input=${(event: Event) => context.mutate((draft) => {
                          draft.blocks[bi].values[vi].label = (event.target as HTMLInputElement).value;
                        })} />
                      <button type="button" title=${t('summary.up')} ?disabled=${vi === 0}
                        @click=${() => context.mutate((draft) => {
                          draft.blocks[bi].values = moveSummaryItem(draft.blocks[bi].values, vi, vi - 1);
                        })}>↑</button>
                      <button type="button" title=${t('summary.down')} ?disabled=${vi === block.values.length - 1}
                        @click=${() => context.mutate((draft) => {
                          draft.blocks[bi].values = moveSummaryItem(draft.blocks[bi].values, vi, vi + 1);
                        })}>↓</button>
                      <button type="button" title=${t('btn.delete')}
                        @click=${() => context.mutate((draft) => {
                          draft.blocks[bi].values.splice(vi, 1);
                        })}><ha-icon icon="mdi:delete-outline"></ha-icon></button>
                    </div>
                    ${fieldProblem(`${vp}.label`)
                      ? html`<div class="summary-problem error">${problemText(fieldProblem(`${vp}.label`))}</div>` : nothing}
                    <select class="summary-source" .value=${sourceToken}
                      data-summary-error=${String(dialog.attempted && firstError?.path === `${vp}.source`)}
                      @change=${(event: Event) => context.setSource(
                        bi, vi, (event.target as HTMLSelectElement).value,
                      )}>
                      <optgroup label=${t('summary.system_group')}>
                        <option value="system:device_count" ?selected=${sourceToken === 'system:device_count'}>${t('summary.system.device_count')}</option>
                        <option value="system:total_area" ?selected=${sourceToken === 'system:total_area'}>${t('summary.system.total_area')}</option>
                        <option value="system:datetime" ?selected=${sourceToken === 'system:datetime'}>${t('summary.system.datetime')}</option>
                      </optgroup>
                      <optgroup label=${t('summary.entities_group')}>
                        ${value.source.type === 'entity' && !value.source.entity_id
                          ? html`<option value="entity:" selected>${t('summary.select_source')}</option>` : nothing}
                        ${value.source.type === 'entity' && !entities.some(([id]) => id === value.source.entity_id)
                          ? html`<option value=${`entity:${value.source.entity_id}`} selected>${
                            host.hass?.states?.[value.source.entity_id]?.attributes?.friendly_name || value.source.entity_id
                          } — ${value.source.entity_id}</option>` : nothing}
                        ${entities.map(([id, state]) => html`<option value=${`entity:${id}`}
                          ?selected=${sourceToken === `entity:${id}`}>
                          ${state.attributes?.friendly_name || id} — ${id}
                        </option>`)}
                      </optgroup>
                    </select>
                    ${sourceProblem
                      ? html`<div class="summary-problem ${sourceProblem.kind}">${problemText(sourceProblem)}</div>` : nothing}
                  </div>`;
                })}
                <button class="btn ghost summary-add" type="button"
                  ?disabled=${block.values.length >= 20}
                  title=${block.values.length >= 20 ? t('summary.limit_values') : ''}
                  @click=${() => context.mutate((draft) => {
                    draft.blocks[bi].values.push(newSummaryValue(t));
                  })}>
                  <ha-icon icon="mdi:plus"></ha-icon>${t('summary.add_value')}
                </button>
              </div>
            </article>`;
          })}
        </div>
        <button class="btn ghost summary-add" type="button"
          ?disabled=${dialog.draft.blocks.length >= 10}
          title=${dialog.draft.blocks.length >= 10 ? t('summary.limit_blocks') : ''}
          @click=${() => context.mutate((draft) => {
            draft.blocks.push(newSummaryBlock(t));
          })}>
          <ha-icon icon="mdi:plus"></ha-icon>${t('summary.add_block')}
        </button>
        ${dialog.error ? html`<div class="summary-problem error" role="alert">${dialog.error}</div>` : nothing}
        ${dialog.conflict ? html`<button class="btn ghost summary-reload" type="button"
          ?disabled=${dialog.busy} @click=${() => context.reload()}>
          <ha-icon icon="mdi:reload"></ha-icon>${t('summary.reload_current')}
        </button>` : nothing}
      `}
    </div>
    <div class="row" slot="footer">
      <button class="btn ghost" ?disabled=${dialog.busy} @click=${close}>${t('btn.cancel')}</button>
      <span class="spacer"></span>
      <button class="btn on" ?disabled=${dialog.localOnly ? !changed || dialog.busy : !canSave}
        @click=${() => context.save()}><ha-icon icon="mdi:check"></ha-icon>${t('btn.save')}</button>
    </div>
  </hp-dialog>`;
};