import { describe, expect, it, mock } from "bun:test"

describe("experimental.session.compacting handler", () => {
  function createCompactingHandler(hooks: {
    compactionTodoPreserver?: { capture: (sessionID: string) => Promise<void> }
    claudeCodeHooks?: {
      "experimental.session.compacting"?: (
        input: { sessionID: string },
        output: { context: string[] },
      ) => Promise<void>
    }
    compactionContextInjector?: (sessionID: string) => string
  }) {
    return async (
      _input: { sessionID: string },
      output: { context: string[] },
    ): Promise<void> => {
      await hooks.compactionTodoPreserver?.capture(_input.sessionID)
      await hooks.claudeCodeHooks?.["experimental.session.compacting"]?.(
        _input,
        output,
      )
      if (hooks.compactionContextInjector) {
        output.context.push(hooks.compactionContextInjector(_input.sessionID))
      }
    }
  }

  //#given all three hooks are present
  //#when compacting handler is invoked
  //#then all hooks are called in order: capture → PreCompact → contextInjector
  it("calls claudeCodeHooks PreCompact alongside other hooks", async () => {
    const callOrder: string[] = []

    const handler = createCompactingHandler({
      compactionTodoPreserver: {
        capture: mock(async () => { callOrder.push("capture") }),
      },
      claudeCodeHooks: {
        "experimental.session.compacting": mock(async () => {
          callOrder.push("preCompact")
        }),
      },
      compactionContextInjector: mock((sessionID: string) => {
        callOrder.push("contextInjector")
        return `context-for-${sessionID}`
      }),
    })

    const output = { context: [] as string[] }
    await handler({ sessionID: "ses_test" }, output)

    expect(callOrder).toEqual(["capture", "preCompact", "contextInjector"])
    expect(output.context).toEqual(["context-for-ses_test"])
  })

  //#given claudeCodeHooks injects context during PreCompact
  //#when compacting handler is invoked
  //#then injected context from PreCompact is preserved in output
  it("preserves context injected by PreCompact hooks", async () => {
    const handler = createCompactingHandler({
      claudeCodeHooks: {
        "experimental.session.compacting": async (_input, output) => {
          output.context.push("precompact-injected-context")
        },
      },
    })

    const output = { context: [] as string[] }
    await handler({ sessionID: "ses_test" }, output)

    expect(output.context).toContain("precompact-injected-context")
  })

  //#given claudeCodeHooks is null (no claude code hooks configured)
  //#when compacting handler is invoked
  //#then handler completes without error and other hooks still run
  it("handles null claudeCodeHooks gracefully", async () => {
    const captureMock = mock(async () => {})
    const contextMock = mock(() => "injected-context")

    const handler = createCompactingHandler({
      compactionTodoPreserver: { capture: captureMock },
      claudeCodeHooks: undefined,
      compactionContextInjector: contextMock,
    })

    const output = { context: [] as string[] }
    await handler({ sessionID: "ses_test" }, output)

    expect(captureMock).toHaveBeenCalledWith("ses_test")
    expect(contextMock).toHaveBeenCalledWith("ses_test")
    expect(output.context).toEqual(["injected-context"])
  })

  //#given compactionContextInjector is null
  //#when compacting handler is invoked
  //#then handler does not early-return, PreCompact hooks still execute
  it("does not early-return when compactionContextInjector is null", async () => {
    const preCompactMock = mock(async () => {})

    const handler = createCompactingHandler({
      claudeCodeHooks: {
        "experimental.session.compacting": preCompactMock,
      },
      compactionContextInjector: undefined,
    })

    const output = { context: [] as string[] }
    await handler({ sessionID: "ses_test" }, output)

    expect(preCompactMock).toHaveBeenCalled()
    expect(output.context).toEqual([])
  })
})

/**
 * Tests for conditional tool registration logic in index.ts
 * 
 * The actual plugin initialization is complex to test directly,
 * so we test the underlying logic that determines tool registration.
 */
describe("look_at tool conditional registration", () => {
  describe("isMultimodalLookerEnabled logic", () => {
    // given multimodal-looker is in disabled_agents
    // when checking if agent is enabled
    // then should return false (disabled)
    it("returns false when multimodal-looker is disabled (exact case)", () => {
      const disabledAgents: string[] = ["multimodal-looker"]
      const isEnabled = !disabledAgents.some(
        (agent) => agent.toLowerCase() === "multimodal-looker"
      )
      expect(isEnabled).toBe(false)
    })

    // given multimodal-looker is in disabled_agents with different case
    // when checking if agent is enabled
    // then should return false (case-insensitive match)
    it("returns false when multimodal-looker is disabled (case-insensitive)", () => {
      const disabledAgents: string[] = ["Multimodal-Looker"]
      const isEnabled = !disabledAgents.some(
        (agent) => agent.toLowerCase() === "multimodal-looker"
      )
      expect(isEnabled).toBe(false)
    })

    // given multimodal-looker is NOT in disabled_agents
    // when checking if agent is enabled
    // then should return true (enabled)
    it("returns true when multimodal-looker is not disabled", () => {
      const disabledAgents: string[] = ["oracle", "librarian"]
      const isEnabled = !disabledAgents.some(
        (agent) => agent.toLowerCase() === "multimodal-looker"
      )
      expect(isEnabled).toBe(true)
    })

    // given disabled_agents is empty
    // when checking if agent is enabled
    // then should return true (enabled by default)
    it("returns true when disabled_agents is empty", () => {
      const disabledAgents: string[] = []
      const isEnabled = !disabledAgents.some(
        (agent) => agent.toLowerCase() === "multimodal-looker"
      )
      expect(isEnabled).toBe(true)
    })

    // given disabled_agents is undefined (simulated as empty array)
    // when checking if agent is enabled
    // then should return true (enabled by default)
    it("returns true when disabled_agents is undefined (fallback to empty)", () => {
      const disabledAgents: string[] | undefined = undefined
      const list: string[] = disabledAgents ?? []
      const isEnabled = !list.some(
        (agent) => agent.toLowerCase() === "multimodal-looker"
      )
      expect(isEnabled).toBe(true)
    })
  })

  describe("conditional tool spread pattern", () => {
    // given lookAt is not null (agent enabled)
    // when spreading into tool object
    // then look_at should be included
    it("includes look_at when lookAt is not null", () => {
      const lookAt = { execute: () => {} } // mock tool
      const tools = {
        ...(lookAt ? { look_at: lookAt } : {}),
      }
      expect(tools).toHaveProperty("look_at")
    })

    // given lookAt is null (agent disabled)
    // when spreading into tool object
    // then look_at should NOT be included
    it("excludes look_at when lookAt is null", () => {
      const lookAt = null
      const tools = {
        ...(lookAt ? { look_at: lookAt } : {}),
      }
      expect(tools).not.toHaveProperty("look_at")
    })
  })
})