package main

// A step's room to work and its workspace's end (novox/hq issue 1839, ADR 0509): every step is refused while the work
// or toolchain cache filesystem is under the floor, a workspace is held while a step runs on it, removed when its caller releases
// it, and swept unheld past buildstep.UnheldBound.

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

// ReleaseTool removes a workspace whose caller's steps have ended.
const ReleaseTool = "build_node_release"

// floorOf is the floor the module keeps on node: build-agent's.
func floorOf(node string) buildstep.Floor {
	return buildstep.Floor{Node: node, Bytes: buildstep.FreeSpaceFloor}
}

// room refuses while the work or toolchain cache filesystem is under the floor.
func (m *Module) room() error {
	paths := []string{m.Work}
	if m.Toolchain != nil {
		paths = append(paths, m.Toolchain.Paths.Cache)
	}
	return m.Floor.Check(paths...)
}

// spaces are the module's workspaces under Work.
func (m *Module) spaces() *buildstep.Workspaces {
	m.spacesOnce.Do(func() { m.workspaces = &buildstep.Workspaces{Dir: m.Work} })
	return m.workspaces
}

// holdArg holds the workspace a step's arguments name while the step runs; nothing when they name none.
func (m *Module) holdArg(args map[string]any) func() {
	ws, _ := args["workspace"].(string)
	if ws == "" {
		return func() {}
	}
	return m.spaces().Hold(ws)
}

// releaseTool is build_node_release: no guard and no floor, since it only frees room.
func (m *Module) releaseTool() stdio.Tool {
	return stdio.Tool{Name: ReleaseTool,
		Description: "Remove a workspace whose steps have ended (fetch, test, build): its caller says so once its last step " +
			"answered. A workspace already gone is no error; one a running step holds is refused. A workspace never released " +
			"is removed two hours after its last use.",
		Input: map[string]any{"type": "object", "properties": map[string]any{
			"workspace": map[string]any{"type": "string", "description": "the workspace id a fetch answered"},
		}, "required": []string{"workspace"}},
		Run: func(args map[string]any) (any, error) {
			ws, _ := args["workspace"].(string)
			if err := m.spaces().Release(ws); err != nil {
				return nil, err
			}
			return map[string]any{"released": ws}, nil
		}}
}

// sweepSaid is CleanWorkspaces' saying of a workspace a caller never released: a fault of the caller (ADR 0509).
func (m *Module) sweepSaid(removed []string) {
	if len(removed) > 0 && m.Say != nil {
		m.Say("removed %d workspaces no caller released within %s: %v", len(removed), buildstep.UnheldBound, removed)
	}
}