/**
 * @license
 * Copyright 2019 Google LLC
 * SPDX-License-Identifier: Apache-2.0
 */

// Former goog.module ID: Blockly.geras.RenderInfo

import type {BlockSvg} from '../../block_svg.js';
import type {Input} from '../../inputs/input.js';
import {RenderInfo as BaseRenderInfo} from '../common/info.js';
import type {Measurable} from '../measurables/base.js';
import type {BottomRow} from '../measurables/bottom_row.js';
import {DummyInput} from '../../inputs/dummy_input.js';
import {EndRowInput} from '../../inputs/end_row_input.js';
import {ExternalValueInput} from '../measurables/external_value_input.js';
import type {Field} from '../measurables/field.js';
import {InRowSpacer} from '../measurables/in_row_spacer.js';
import type {InputRow} from '../measurables/input_row.js';
import type {Row} from '../measurables/row.js';
import {StatementInput} from '../../inputs/statement_input.js';
import type {TopRow} from '../measurables/top_row.js';
import {Types} from '../measurables/types.js';
import {ValueInput} from '../../inputs/value_input.js';

import type {ConstantProvider} from './constants.js';
import {InlineInput} from './measurables/inline_input.js';
import {StatementInput as StatementInputMeasurable} from './measurables/statement_input.js';
import type {Renderer} from './renderer.js';

/**
 * An object containing all sizing information needed to draw this block,
 * customized for the geras renderer.
 *
 * This measure pass does not propagate changes to the block (although fields
 * may choose to rerender when getSize() is called).  However, calling it
 * repeatedly may be expensive.
 */
export class RenderInfo extends BaseRenderInfo {
  // TODO(b/109816955): remove '!', see go/strict-prop-init-fix.
  override constants_!: ConstantProvider;

  protected override readonly renderer_: Renderer;

  /**
   * @param renderer The renderer in use.
   * @param block The block to measure.
   */
  constructor(renderer: Renderer, block: BlockSvg) {
    super(renderer, block);
    this.renderer_ = renderer;
  }

  /**
   * Get the block renderer in use.
   *
   * @returns The block renderer in use.
   */
  override getRenderer(): Renderer {
    return this.renderer_;
  }

  override populateBottomRow_() {
    super.populateBottomRow_();

    const followsStatement =
      this.block_.inputList.length &&
      this.block_.inputList[this.block_.inputList.length - 1] instanceof
        StatementInput;
    // The minimum height of the bottom row is smaller in Geras than in other
    // renderers, because the dark path adds a pixel.
    // If one of the row's elements has a greater height this will be
    // overwritten in the compute pass.
    if (!followsStatement) {
      this.bottomRow.minHeight =
        this.constants_.MEDIUM_PADDING - this.constants_.DARK_PATH_OFFSET;
    }
  }

  override addInput_(input: Input, activeRow: Row) {
    // Non-dummy inputs have visual representations onscreen.
    if (this.isInline && input instanceof ValueInput) {
      activeRow.elements.push(new InlineInput(this.constants_, input));
      activeRow.hasInlineInput = true;
    } else if (input instanceof StatementInput) {
      activeRow.elements.push(
        new StatementInputMeasurable(this.constants_, input),
      );
      activeRow.hasStatement = true;
    } else if (input instanceof ValueInput) {
      activeRow.elements.push(new ExternalValueInput(this.constants_, input));
      activeRow.hasExternalInput = true;
    } else if (input instanceof DummyInput || input instanceof EndRowInput) {
      // Dummy and end-row inputs have no visual representation, but the
      // information is still important.
      activeRow.minHeight = Math.max(
        activeRow.minHeight,
        this.constants_.DUMMY_INPUT_MIN_HEIGHT,
      );
      activeRow.hasDummyInput = true;
    }
    // Ignore row alignment if inline.
    if (!this.isInline && activeRow.align === null) {
      activeRow.align = input.align;
    }
  }

  override addElemSpacing_() {
    let hasExternalInputs = false;
    for (let i = 0, row; (row = this.rows[i]); i++) {
      if (row.hasExternalInput) {
        hasExternalInputs = true;
      }
    }
    for (let i = 0, row; (row = this.rows[i]); i++) {
      const oldElems = row.elements;
      row.elements = [];
      // No spacing needed before the corner on the top row or the bottom row.
      if (row.startsWithElemSpacer()) {
        // There's a spacer before the first element in the row.
        row.elements.push(
          new InRowSpacer(
            this.constants_,
            this.getInRowSpacing_(null, oldElems[0]),
          ),
        );
      }
      if (!oldElems.length) {
        continue;
      }
      for (let e = 0; e < oldElems.length - 1; e++) {
        row.elements.push(oldElems[e]);
        const spacing = this.getInRowSpacing_(oldElems[e], oldElems[e + 1]);
        row.elements.push(new InRowSpacer(this.constants_, spacing));
      }
      row.elements.push(oldElems[oldElems.length - 1]);
      if (row.endsWithElemSpacer()) {
        let spacing = this.getInRowSpacing_(
          oldElems[oldElems.length - 1],
          null,
        );
        if (hasExternalInputs && row.hasDummyInput) {
          spacing += this.constants_.TAB_WIDTH;
        }
        // There's a spacer after the last element in the row.
        row.elements.push(new InRowSpacer(this.constants_, spacing));
      }
    }
  }

  override getInRowSpacing_(prev: Measurable | null, next: Measurable | null) {
    if (!prev) {
      // Between an editable field and the beginning of the row.
      if (next && Types.isField(next) && (next as Field).isEditable) {
        return this.constants_.MEDIUM_PADDING;
      }
      // Inline input at the beginning of the row.
      if (next && Types.isInlineInput(next)) {
        return this.constants_.MEDIUM_LARGE_PADDING;
      }
      if (next && Types.isStatementInput(next)) {
        return this.constants_.STATEMENT_INPUT_PADDING_LEFT;
      }
      // Anything else at the beginning of the row.
      return this.constants_.LARGE_PADDING;
    }

    // Spacing between a non-input and the end of the row or a statement input.
    if (!Types.isInput(prev) && (!next || Types.isStatementInput(next))) {
      // Between an editable field and the end of the row.
      if (Types.isField(prev) && (prev as Field).isEditable) {
        return this.constants_.MEDIUM_PADDING;
      }
      // Padding at the end of an icon-only row to make the block shape clearer.
      if (Types.isIcon(prev)) {
        return this.constants_.LARGE_PADDING * 2 + 1;
      }
      if (Types.isHat(prev)) {
        return this.constants_.NO_PADDING;
      }
      // Establish a minimum width for a block with a previous or next
      // connection.
      if (Types.isPreviousOrNextConnection(prev)) {
        return this.constants_.LARGE_PADDING;
      }
      // Between rounded corner and the end of the row.
      if (Types.isLeftRoundedCorner(prev)) {
        return this.constants_.MIN_BLOCK_WIDTH;
      }
      // Between a jagged edge and the end of the row.
      if (Types.isJaggedEdge(prev)) {
        return this.constants_.NO_PADDING;
      }
      // Between noneditable fields and icons and the end of the row.
      return this.constants_.LARGE_PADDING;
    }

    // Between inputs and the end of the row.
    if (Types.isInput(prev) && !next) {
      if (Types.isExternalInput(prev)) {
        return this.constants_.NO_PADDING;
      } else if (Types.isInlineInput(prev)) {
        return this.constants_.LARGE_PADDING;
      } else if (Types.isStatementInput(prev)) {
        return this.constants_.NO_PADDING;
      }
    }

    // Spacing between a non-input and an input.
    if (!Types.isInput(prev) && next && Types.isInput(next)) {
      // Between an editable field and an input.
      if (Types.isField(prev) && (prev as Field).isEditable) {
        if (Types.isInlineInput(next)) {
          return this.constants_.SMALL_PADDING;
        } else if (Types.isExternalInput(next)) {
          return this.constants_.SMALL_PADDING;
        }
      } else {
        if (Types.isInlineInput(next)) {
          return this.constants_.MEDIUM_LARGE_PADDING;
        } else if (Types.isExternalInput(next)) {
          return this.constants_.MEDIUM_LARGE_PADDING;
        } else if (Types.isStatementInput(next)) {
          return this.constants_.LARGE_PADDING;
        }
      }
      return this.constants_.LARGE_PADDING - 1;
    }

    // Spacing between an icon and an icon or field.
    if (Types.isIcon(prev) && next && !Types.isInput(next)) {
      return this.constants_.LARGE_PADDING;
    }
    // Spacing between an inline input and a field.
    if (Types.isInlineInput(prev) && next && Types.isField(next)) {
      // Editable field after inline input.
      if ((next as Field).isEditable) {
        return this.constants_.MEDIUM_PADDING;
      } else {
        // Noneditable field after inline input.
        return this.constants_.LARGE_PADDING;
      }
    }

    if (Types.isLeftSquareCorner(prev) && next) {
      // Spacing between a hat and a corner
      if (Types.isHat(next)) {
        return this.constants_.NO_PADDING;
      }
      // Spacing between a square corner and a previous or next connection
      if (Types.isPreviousConnection(next)) {
        return next.notchOffset;
      } else if (Types.isNextConnection(next)) {
        // Next connections are shifted slightly to the left (in both LTR and
        // RTL) to make the dark path under the previous connection show
        // through.
        const offset =
          ((this.RTL ? 1 : -1) * this.constants_.DARK_PATH_OFFSET) / 2;
        return next.notchOffset + offset;
      }
    }

    // Spacing between a rounded corner and a previous or next connection.
    if (Types.isLeftRoundedCorner(prev) && next) {
      if (Types.isPreviousConnection(next)) {
        return next.notchOffset - this.constants_.CORNER_RADIUS;
      } else if (Types.isNextConnection(next)) {
        // Next connections are shifted slightly to the left (in both LTR and
        // RTL) to make the dark path under the previous connection show
        // through.
        const offset =
          ((this.RTL ? 1 : -1) * this.constants_.DARK_PATH_OFFSET) / 2;
        return next.notchOffset - this.constants_.CORNER_RADIUS + offset;
      }
    }

    // Spacing between two fields of the same editability.
    if (
      Types.isField(prev) &&
      next &&
      Types.isField(next) &&
      (prev as Field).isEditable === (next as Field).isEditable
    ) {
      return this.constants_.LARGE_PADDING;
    }

    // Spacing between anything and a jagged edge.
    if (next && Types.isJaggedEdge(next)) {
      return this.constants_.LARGE_PADDING;
    }

    return this.constants_.MEDIUM_PADDING;
  }

  override getSpacerRowHeight_(prev: Row, next: Row) {
    // If we have an empty block add a spacer to increase the height.
    if (Types.isTopRow(prev) && Types.isBottomRow(next)) {
      return this.constants_.EMPTY_BLOCK_SPACER_HEIGHT;
    }
    // Top and bottom rows act as a spacer so we don't need any extra padding.
    if (Types.isTopRow(prev) || Types.isBottomRow(next)) {
      return this.constants_.NO_PADDING;
    }
    if (prev.hasExternalInput && next.hasExternalInput) {
      return this.constants_.LARGE_PADDING;
    }
    if (!prev.hasStatement && next.hasStatement) {
      return this.constants_.BETWEEN_STATEMENT_PADDING_Y;
    }
    if (prev.hasStatement && next.hasStatement) {
      return this.constants_.LARGE_PADDING;
    }
    if (!prev.hasStatement && next.hasDummyInput) {
      return this.constants_.LARGE_PADDING;
    }
    if (prev.hasDummyInput) {
      return this.constants_.LARGE_PADDING;
    }
    return this.constants_.MEDIUM_PADDING;
  }

  override getElemCenterline_(row: Row, elem: Measurable) {
    if (Types.isSpacer(elem)) {
      return row.yPos + elem.height / 2;
    }
    if (Types.isBottomRow(row)) {
      const bottomRow = row as BottomRow;
      const baseline =
        bottomRow.yPos + bottomRow.height - bottomRow.descenderHeight;
      if (Types.isNextConnection(elem)) {
        return baseline + elem.height / 2;
      }
      return baseline - elem.height / 2;
    }
    if (Types.isTopRow(row)) {
      const topRow = row as TopRow;
      if (Types.isHat(elem)) {
        return topRow.capline - elem.height / 2;
      }
      return topRow.capline + elem.height / 2;
    }

    let result = row.yPos;
    if (Types.isField(elem) || Types.isIcon(elem)) {
      result += elem.height / 2;
      if (
        (row.hasInlineInput || row.hasStatement) &&
        elem.height + this.constants_.TALL_INPUT_FIELD_OFFSET_Y <= row.height
      ) {
        result += this.constants_.TALL_INPUT_FIELD_OFFSET_Y;
      }
    } else if (Types.isInlineInput(elem)) {
      result += elem.height / 2;
    } else {
      result += row.height / 2;
    }
    return result;
  }

  override alignRowElements_() {
    if (!this.isInline) {
      super.alignRowElements_();
      return;
    }
    // Walk backgrounds through rows on the block, keeping track of the right
    // input edge.
    let nextRightEdge = 0;
    const rowNextRightEdges = new WeakMap();
    let prevInput = null;
    for (let i = this.rows.length - 1, row; (row = this.rows[i]); i--) {
      rowNextRightEdges.set(row, nextRightEdge);
      if (Types.isInputRow(row)) {
        if (row.hasStatement) {
          this.alignStatementRow_(row as InputRow);
        }
        if (
          prevInput &&
          prevInput.hasStatement &&
          row.width < prevInput.width
        ) {
          rowNextRightEdges.set(row, prevInput.width);
        } else if (row.hasStatement) {
          nextRightEdge = row.width;
        } else {
          // To keep right edges of consecutive non-statement rows aligned, use
          // the maximum width.
          nextRightEdge = Math.max(nextRightEdge, row.width);
        }
        prevInput = row;
      }
    }
    // Walk down each row from the top, comparing the prev and next right input
    // edges and setting the desired width to the max of the two.
    let prevRightEdge = 0;
    for (let i = 0, row; (row = this.rows[i]); i++) {
      if (row.hasStatement) {
        prevRightEdge = this.getDesiredRowWidth_(row);
      } else if (Types.isSpacer(row)) {
        // Set the spacer row to the max of the prev or next input width.
        row.width = Math.max(prevRightEdge, rowNextRightEdges.get(row));
      } else {
        const currentWidth = row.width;
        const desiredWidth = Math.max(
          prevRightEdge,
          rowNextRightEdges.get(row),
        );
        const missingSpace = desiredWidth - currentWidth;
        if (missingSpace > 0) {
          this.addAlignmentPadding_(row, missingSpace);
        }
        prevRightEdge = row.width;
      }
    }
  }

  override getDesiredRowWidth_(row: Row) {
    // Limit the width of a statement row when a block is inline.
    if (this.isInline && row.hasStatement) {
      return (
        this.statementEdge + this.constants_.MAX_BOTTOM_WIDTH + this.startX
      );
    }
    return super.getDesiredRowWidth_(row);
  }

  override finalize_() {
    // Performance note: this could be combined with the draw pass, if the time
    // that this takes is excessive.  But it shouldn't be, because it only
    // accesses and sets properties that already exist on the objects.
    let widestRowWithConnectedBlocks = 0;
    let yCursor = 0;
    for (let i = 0, row; (row = this.rows[i]); i++) {
      row.yPos = yCursor;
      row.xPos = this.startX;
      yCursor += row.height;

      widestRowWithConnectedBlocks = Math.max(
        widestRowWithConnectedBlocks,
        row.widthWithConnectedBlocks,
      );
      // Add padding to the bottom row if block height is less than minimum
      const heightWithoutHat = yCursor - this.topRow.ascenderHeight;
      if (
        row === this.bottomRow &&
        heightWithoutHat < this.constants_.MIN_BLOCK_HEIGHT
      ) {
        // But the hat height shouldn't be part of this.
        const diff = this.constants_.MIN_BLOCK_HEIGHT - heightWithoutHat;
        this.bottomRow.height += diff;
        yCursor += diff;
      }
      this.recordElemPositions_(row);
    }
    if (
      this.outputConnection &&
      this.block_.nextConnection &&
      this.block_.nextConnection.isConnected()
    ) {
      const target = this.block_.nextConnection.targetBlock();
      if (target) {
        // Include width of connected block in value to stack width measurement.
        widestRowWithConnectedBlocks = Math.max(
          widestRowWithConnectedBlocks,
          target.getHeightWidth().width - this.constants_.DARK_PATH_OFFSET,
        );
      }
    }

    this.bottomRow.baseline = yCursor - this.bottomRow.descenderHeight;
    this.widthWithChildren =
      widestRowWithConnectedBlocks +
      this.startX +
      this.constants_.DARK_PATH_OFFSET;
    this.width += this.constants_.DARK_PATH_OFFSET;
    this.height = yCursor + this.constants_.DARK_PATH_OFFSET;
    this.startY = this.topRow.capline;
  }
}