import { describe, expect, test } from "vitest"
import {
  isClosedBorder,
  selectBorderVariant,
  getPerimeterOpenings,
  SPECIAL_PRESETS_BY_LEVEL,
  generateWilderness,
} from "../src/game/wilderness.ts"
import type { WildernessPiece } from "../src/game/wilderness.ts"
import { Rng } from "../src/game/rng.ts"
import type { Ds1, Ds1Cell } from "../src/formats/ds1.ts"

function makeMockDs1(width: number, height: number, hasGapInWalls: boolean): Ds1 {
  const cells: Ds1Cell[][] = []
  for (let y = 0; y < height; y += 1) {
    const row: Ds1Cell[] = []
    for (let x = 0; x < width; x += 1) {
      const isGap = hasGapInWalls && x === Math.floor(width / 2)
      row.push({
        walls: isGap ? [] : [{ prop1: 2, sequence: 0, style: 1, type: 0, unknown1: 0, unknown2: 0, hidden: false }],
        floors: [{ prop1: 2, sequence: 0, style: 1, unknown1: 0, unknown2: 0, hidden: false }],
        shadows: [],
        substitutions: [],
      })
    }
    cells.push(row)
  }
  return {
    version: 18,
    width,
    height,
    act: 1,
    substitutionType: 0,
    wallLayers: 1,
    floorLayers: 1,
    cells,
    objects: [],
    npcPathOffset: null,
  }
}

describe("Wilderness Features & Border Rules", () => {
  test("isClosedBorder identifies continuous vs open wall presets", () => {
    const closed = makeMockDs1(8, 8, false)
    const open = makeMockDs1(8, 8, true)

    expect(isClosedBorder(closed, "south")).toBe(true)
    expect(isClosedBorder(closed, "north")).toBe(true)
    expect(isClosedBorder(open, "south")).toBe(false)
    expect(isClosedBorder(open, "north")).toBe(false)
  })

  test("getPerimeterOpenings enforces 0 exits for Cow Level and 1 entrance/1 exit for Blood Moor", () => {
    const cowOpenings = getPerimeterOpenings(39, 10, 10)
    expect(cowOpenings.size).toBe(0)

    const bloodMoorOpenings = getPerimeterOpenings(2, 10, 10)
    expect(bloodMoorOpenings.size).toBe(2)
    expect(bloodMoorOpenings.has("5,9")).toBe(true)
    expect(bloodMoorOpenings.has("9,5")).toBe(true)
  })

  test("selectBorderVariant picks open variant for openings and closed variant for closed walls", () => {
    const closedDs1 = makeMockDs1(8, 8, false)
    const openDs1 = makeMockDs1(8, 8, true)
    const piece: WildernessPiece = {
      name: "Act 1 - Wild Border 1",
      border: true,
      levels: [closedDs1, openDs1],
    }

    const rng = new Rng(12345)
    const pickedOpen = selectBorderVariant(piece, "south", true, rng)
    expect(isClosedBorder(pickedOpen, "south")).toBe(false)

    const pickedClosed = selectBorderVariant(piece, "south", false, rng)
    expect(isClosedBorder(pickedClosed, "south")).toBe(true)
  })

  test("SPECIAL_PRESETS_BY_LEVEL contains stone walls and river presets", () => {
    const bloodMoorPresets = SPECIAL_PRESETS_BY_LEVEL[2]
    expect(bloodMoorPresets).toBeDefined()
    expect(bloodMoorPresets).toContain("Act 1 - Corral Fill")
    expect(bloodMoorPresets).toContain("Act 1 - Fence Fill 4")
    expect(bloodMoorPresets).toContain("Act 1 - River Upper")
    expect(bloodMoorPresets).toContain("Act 1 - Bridge")

    const cowPresets = SPECIAL_PRESETS_BY_LEVEL[39]
    expect(cowPresets).toBeDefined()
    expect(cowPresets).toContain("Act 1 - Corral Fill")
    expect(cowPresets).toContain("Act 1 - Fence Fill 4")
    expect(cowPresets).toContain("Act 1 - Fence Fill 5")
    expect(cowPresets).toContain("Act 1 - Bivouac")
    expect(cowPresets).toContain("Act 1 - Pond")
  })

  test("generateWilderness generates Level 2 with river or pond deterministically by seed", () => {
    const closedDs1 = makeMockDs1(8, 8, false)
    const piece: WildernessPiece = {
      name: "Act 1 - Wild Border 1",
      border: true,
      levels: [closedDs1],
    }
    const riverPiece: WildernessPiece = {
      name: "Act 1 - River Upper",
      border: false,
      levels: [closedDs1],
    }
    const pondPiece: WildernessPiece = {
      name: "Act 1 - Pond",
      border: false,
      levels: [closedDs1],
    }
    const corralPiece: WildernessPiece = {
      name: "Act 1 - Corral Fill",
      border: false,
      levels: [closedDs1],
    }

    const result = generateWilderness({
      levelId: 2,
      levelName: "Blood Moor",
      levelTypeName: "Act 1 - Wilderness",
      sizeX: 80,
      sizeY: 80,
      subType: 6,
      subTheme: 0,
      seed: 12345,
      pieces: [piece, riverPiece, pondPiece, corralPiece],
      substitutions: [],
    })

    expect(result.stats.blockGrid).toEqual({ width: 10, height: 10 })
    expect(result.level.width).toBe(80)
    expect(result.level.height).toBe(80)
  })
})