lightspeed

//// Deterministic ecosystem integration harness for M26.

import gleam/int
import gleam/list
import gleam/string
import lightspeed/data/repository
import lightspeed/integration/data
import lightspeed/integration/jobs
import lightspeed/integration/mail
import lightspeed/integration/ops
import lightspeed/integration/stack

pub const snapshot_version = 1

/// M26 conformance scenarios.
pub type Scenario {
  ReferenceStacks
  MixedRuntimeCookbook
  OperatorRunMonitorRollbackIncident
  ReproducibleSetupTeardown
}

/// One M26 scenario outcome.
pub type ScenarioOutcome {
  ScenarioOutcome(
    scenario: Scenario,
    passed: Bool,
    deterministic: Bool,
    signature: String,
  )
}

/// Full M26 report.
pub type Report {
  Report(
    outcomes: List(ScenarioOutcome),
    failed_scenarios: Int,
    nondeterministic_failures: Int,
  )
}

/// Run all M26 scenarios.
pub fn run_matrix() -> Report {
  let outcomes =
    [
      ReferenceStacks,
      MixedRuntimeCookbook,
      OperatorRunMonitorRollbackIncident,
      ReproducibleSetupTeardown,
    ]
    |> list.map(run_scenario)

  Report(
    outcomes: outcomes,
    failed_scenarios: count_failed(outcomes),
    nondeterministic_failures: count_nondeterministic(outcomes),
  )
}

/// Run one scenario twice and require deterministic parity.
pub fn run_scenario(scenario: Scenario) -> ScenarioOutcome {
  let #(first_passed, first_signature) = evaluate(scenario)
  let #(second_passed, second_signature) = evaluate(scenario)
  let deterministic =
    first_passed == second_passed && first_signature == second_signature
  let passed = first_passed && second_passed && deterministic

  ScenarioOutcome(
    scenario: scenario,
    passed: passed,
    deterministic: deterministic,
    signature: first_signature,
  )
}

/// Scenario label.
pub fn scenario_label(scenario: Scenario) -> String {
  case scenario {
    ReferenceStacks -> "reference_stacks"
    MixedRuntimeCookbook -> "mixed_runtime_cookbook"
    OperatorRunMonitorRollbackIncident ->
      "operator_run_monitor_rollback_incident"
    ReproducibleSetupTeardown -> "reproducible_setup_teardown"
  }
}

/// Stable pass/fail label.
pub fn pass_fail_label(outcome: ScenarioOutcome) -> String {
  case outcome.passed {
    True -> "pass"
    False -> "fail"
  }
}

/// Scenario signature.
pub fn signature(outcome: ScenarioOutcome) -> String {
  outcome.signature
}

/// Scenario accessor.
pub fn scenario(outcome: ScenarioOutcome) -> Scenario {
  outcome.scenario
}

/// Outcome determinism accessor.
pub fn deterministic(outcome: ScenarioOutcome) -> Bool {
  outcome.deterministic
}

/// Report outcomes.
pub fn outcomes(report: Report) -> List(ScenarioOutcome) {
  report.outcomes
}

/// Failed scenario count.
pub fn failed_scenarios(report: Report) -> Int {
  report.failed_scenarios
}

/// Nondeterministic scenario count.
pub fn nondeterministic_failures(report: Report) -> Int {
  report.nondeterministic_failures
}

/// Stable report signature.
pub fn report_signature(report: Report) -> String {
  let entries =
    list.map(report.outcomes, fn(outcome) {
      scenario_label(outcome.scenario)
      <> "="
      <> pass_fail_label(outcome)
      <> ":deterministic="
      <> bool_label(outcome.deterministic)
      <> ":"
      <> outcome.signature
    })

  join_with(";", entries)
}

/// Deterministic snapshot signature for CI fixture drift guards.
pub fn snapshot_signature() -> String {
  "m26.snapshot.v"
  <> int.to_string(snapshot_version)
  <> "|"
  <> report_signature(run_matrix())
}

/// Deterministic markdown report for integration fixture gate scripts.
pub fn snapshot_report_markdown() -> String {
  let report = run_matrix()
  let failed = failed_scenarios(report)
  let nondeterministic = nondeterministic_failures(report)
  let status = case failed == 0 && nondeterministic == 0 {
    True -> "OK"
    False -> "FAIL"
  }

  "# Integration Fixture Report\n\n"
  <> "snapshot_version: "
  <> int.to_string(snapshot_version)
  <> "\n"
  <> "status: "
  <> status
  <> "\n"
  <> "failed_scenarios: "
  <> int.to_string(failed)
  <> "\n"
  <> "nondeterministic_failures: "
  <> int.to_string(nondeterministic)
  <> "\n\n"
  <> "snapshot_signature: "
  <> snapshot_signature()
  <> "\n\n"
  <> "report_signature: "
  <> report_signature(report)
  <> "\n"
}

fn evaluate(scenario: Scenario) -> #(Bool, String) {
  case scenario {
    ReferenceStacks -> evaluate_reference_stacks()
    MixedRuntimeCookbook -> evaluate_mixed_runtime_cookbook()
    OperatorRunMonitorRollbackIncident ->
      evaluate_operator_run_monitor_rollback_incident()
    ReproducibleSetupTeardown -> evaluate_reproducible_setup_teardown()
  }
}

fn evaluate_reference_stacks() -> #(Bool, String) {
  let commerce = stack.commerce_stack()
  let collaboration = stack.collaboration_stack()
  let passed = stack.valid(commerce) && stack.valid(collaboration)

  #(
    passed,
    "commerce="
      <> stack.signature(commerce)
      <> "|collaboration="
      <> stack.signature(collaboration),
  )
}

fn evaluate_mixed_runtime_cookbook() -> #(Bool, String) {
  let mixed = stack.mixed_runtime_stack()
  let data_adapter = repository.adapter_label(data.adapter(mixed.data_pattern))
  let jobs_backend = jobs.backend_label(jobs.backend(mixed.jobs_pattern))
  let mail_backend = mail.backend_label(mail.backend(mixed.mail_pattern))
  let ops_backend = ops.backend_label(ops.backend(mixed.ops_pattern))

  let passed =
    stack.valid(mixed)
    && contains(data_adapter, "mixed_bridge")
    && contains(jobs_backend, "mixed_queue")
    && contains(mail_backend, "mixed_mail")
    && contains(ops_backend, "telemetry_bridge")

  #(
    passed,
    "stack="
      <> stack.signature(mixed)
      <> "|data="
      <> data_adapter
      <> "|jobs="
      <> jobs_backend
      <> "|mail="
      <> mail_backend
      <> "|ops="
      <> ops_backend,
  )
}

fn evaluate_operator_run_monitor_rollback_incident() -> #(Bool, String) {
  let production_ops = ops.production_pattern()
  let mixed_ops = ops.mixed_runtime_pattern()
  let passed = ops.valid(production_ops) && ops.valid(mixed_ops)

  #(
    passed,
    "production="
      <> ops.signature(production_ops)
      <> "|mixed="
      <> ops.signature(mixed_ops),
  )
}

fn evaluate_reproducible_setup_teardown() -> #(Bool, String) {
  let stack_a = stack.collaboration_stack()
  let first = stack.lifecycle_signature(stack_a)
  let second = stack.lifecycle_signature(stack_a)
  let passed = first == second

  #(passed, first)
}

fn count_failed(outcomes: List(ScenarioOutcome)) -> Int {
  case outcomes {
    [] -> 0
    [outcome, ..rest] ->
      case outcome.passed {
        True -> count_failed(rest)
        False -> 1 + count_failed(rest)
      }
  }
}

fn count_nondeterministic(outcomes: List(ScenarioOutcome)) -> Int {
  case outcomes {
    [] -> 0
    [outcome, ..rest] ->
      case outcome.deterministic {
        True -> count_nondeterministic(rest)
        False -> 1 + count_nondeterministic(rest)
      }
  }
}

fn join_with(separator: String, values: List(String)) -> String {
  case values {
    [] -> ""
    [value] -> value
    [value, ..rest] -> value <> separator <> join_with(separator, rest)
  }
}

fn bool_label(value: Bool) -> String {
  case value {
    True -> "true"
    False -> "false"
  }
}

fn contains(haystack: String, needle: String) -> Bool {
  string.contains(haystack, needle)
}