package main

import (
	"context"
	"time"

	stdio "git.novox.be/novox/mesh-sdk/go"
	"git.novox.be/novox/mesh-sdk/go/buildstep"
	"git.novox.be/novox/mesh-sdk/go/delivery"
)

// **The module pulls its seat's asks** (novox/hq ADR 0525 §2-§6, ADR 0536 §4; issue 1887 A3node), as mesh-build-go
// does: the seat node-build-node, delivery first, then check, then recheck, at most the node's build capacity at once
// (its setting `capacity`); each ask runs with the step bodies its tools run, behind the same guard, and ends on the key
// <node>.<ask id>. The tools stay as the hand path (ADR 0525 §8).

// Seat is the node seat this module holds.
const Seat = "node-build-node"

func (m *Module) askSteps(steps []StepTool) buildstep.AskSteps {
	byName := map[string]buildstep.StepFunc{}
	for _, s := range steps {
		run := s.Run
		byName[s.Name] = func(ctx context.Context, args map[string]any) (any, error) {
			defer m.holdArg(args)()
			return run(ctx, args)
		}
	}
	return buildstep.AskSteps{
		Fetch: byName["build_node_fetch"], Build: byName["build_node_build"], Test: byName["build_node_test"],
		Toolchain: func(ctx context.Context) (delivery.ToolchainUsed, error) {
			installed, err := m.Probe(ctx)
			if err != nil {
				return delivery.ToolchainUsed{}, err
			}
			return delivery.ToolchainUsed{Version: installed, Recipe: m.recipe().Version()}, nil
		},
		Release: func(ws string) error { return m.spaces().Release(ws) },
		Logf:    m.Say,
	}
}

// Puller is the module's pull of its seat's asks, on source (the runtime's seat pull when nil).
func (m *Module) Puller(steps []StepTool, source buildstep.AskSource) *buildstep.Puller {
	if source == nil {
		source = buildstep.SeatAsks{Language: delivery.AskNode}
	}
	capacity := m.Capacity
	// The capacity's own change wakes the puller (issue 1887): the runtime's watch of the config value as mesh-config
	// resolved it; the settings file is read only when that watch cannot start. A test's Capacity is its own.
	var watch func(string, func(stdio.ProvisionChange) error) error
	// And the CPU bounds it (issue 1806's follow-up): the configured capacity is an upper bound, the node's build slice
	// gives floor(its quota's cores / the module's cores-per-step) at once, read live; a test judges by its own Capacity.
	// And the node's build hours (a node may build only in a window): outside them it takes
	// nothing new.
	var cores func() float64
	var hours func() (*buildstep.BuildWindow, string)
	if capacity == nil {
		hours = buildstep.NodeBuildHours(m.Settings, m.Node, m.Say)
		capacity = buildstep.NodeCapacity(m.Settings, m.Node, m.Say)
		watch = buildstep.WatchConfigServed
		cores = buildstep.NodeCoresPerStep(m.Settings, buildstep.DefaultCoresPerStep[delivery.AskNode], m.Say)
	}
	ask := m.askSteps(steps)
	var load func(string) ([]byte, error)
	if m.ReadPauses.Get != nil {
		load = func(key string) ([]byte, error) { return m.ReadPauses.Get(key) }
	}
	return &buildstep.Puller{Source: source, Language: delivery.AskNode, Node: m.Node, Put: m.Steps, PausePut: m.Pauses, Load: load,
		Capacity: capacity, WatchConfig: watch, CoresPerStep: cores, BuildHours: hours, Logf: m.Say,
		Run: func(ctx context.Context, a delivery.StepAsk) (any, error) {
			if err := m.Prepare(ctx); err != nil {
				return nil, err
			}
			if err := m.room(); err != nil {
				return nil, err
			}
			return buildstep.RunAsk(ctx, ask, a)
		}}
}

// SeatTools are the seat's verbs on this node (ADR 0525 §10).
func (m *Module) SeatTools(p *buildstep.Puller) []stdio.Tool {
	return buildstep.SeatTools(Seat, "Node", p)
}

// StepEndTool ends one step left running (issue 1890); the module's steps state is the one it reads and writes.
const StepEndTool = "build_node_step_end"

// endLeftRunning is the module's start sweep (issue 1890): it ends the steps of its node that a previous process left
// running (buildstep.EndStaleAtStart; every step names its owner). main runs it once at the start, and the module's test
// runs it through the conformance kit's left-running case.
func (m *Module) endLeftRunning(ctx context.Context, scan buildstep.Scan, booted time.Time, logf func(string, ...any)) {
	buildstep.EndStaleAtStart(ctx, scan, m.Node, booted, logf)
}

// stepScan is the module's steps state as buildstep reads it.
func (m *Module) stepScan() buildstep.Scan {
	return buildstep.ScanOf(stdio.State(delivery.StepsState))
}