package buildstep

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"strings"
	"testing"
	"time"

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

const runCommit = "0123456789abcdef0123456789abcdef01234567"

// recorder is a build module's step tools that record each call.
type recorder struct {
	calls   []string
	fetch   map[string]any
	tests   map[string]bool // package or module directory -> passed
	digests map[string]string
}

func (r *recorder) steps() AskSteps {
	call := func(name string, answer func(args map[string]any) any) StepFunc {
		return func(ctx context.Context, args map[string]any) (any, error) {
			b, _ := json.Marshal(args)
			r.calls = append(r.calls, name+" "+string(b))
			return answer(args), nil
		}
	}
	return AskSteps{
		Fetch: call("fetch", func(map[string]any) any { return r.fetch }),
		Build: call("build", func(args map[string]any) any {
			return map[string]any{"digest": "sha256:" + args["artifact"].(string), "reference": "artifact-store://" + args["artifact"].(string)}
		}),
		Copy:   call("copy", func(args map[string]any) any { return map[string]any{"digest": "sha256:copied"} }),
		Digest: call("digest", func(map[string]any) any { return map[string]any{"level": "unit", "packages": r.digests} }),
		Test: call("test", func(args map[string]any) any {
			passed := true
			if pkgs, ok := args["packages"].([]string); ok {
				for _, p := range pkgs {
					passed = passed && r.tests[p]
				}
			}
			if dir, ok := args["module"].(string); ok {
				passed = r.tests[dir]
			}
			return map[string]any{"passed": passed, "tests": 1}
		}),
		Kept: func(ctx context.Context, level, digest string) (int, bool, error) { return 7, digest == "d-kept", nil },
	}
}

func ask(job any) delivery.StepAsk {
	a := delivery.StepAsk{ID: NewID(), Kind: delivery.AskCheck, Language: delivery.AskGo, Asker: "t", At: time.Now()}
	switch j := job.(type) {
	case delivery.BuildJob:
		a.Build = &j
	case delivery.CheckJob:
		a.Check = &j
	}
	return a
}

// 1887/A3: a build ask fetches once, builds each artifact from the workspace with publish, copies a pinned one without a
// fetch, and answers each artifact's digest and reference.
func TestRunAskBuilds(t *testing.T) {
	r := &recorder{fetch: map[string]any{"workspace": "/w/1"}}
	steps := r.steps()
	var released []string
	steps.Release = func(ws string) error { released = append(released, ws); return nil }
	out, err := RunAsk(context.Background(), steps, ask(delivery.BuildJob{Module: "m", Path: "modules/m", Publish: true,
		Fetch:     map[string]any{"repository": "novox/x", "commit": runCommit},
		Artifacts: []delivery.AskArtifact{{Artifact: "base", From: "registry/b@sha256:00"}, {Artifact: "bundle"}, {Artifact: "lib"}}}))
	if err != nil {
		t.Fatal(err)
	}
	got := strings.Join(r.calls, "\n")
	want := `copy {"artifact":"base","from":"registry/b@sha256:00","module":"m"}
fetch {"commit":"` + runCommit + `","repository":"novox/x"}
build {"artifact":"bundle","module":"modules/m","publish":true,"workspace":"/w/1"}
build {"artifact":"lib","module":"modules/m","publish":true,"workspace":"/w/1"}`
	if got != want {
		t.Fatalf("calls:\n%s\nwant:\n%s", got, want)
	}
	if len(released) != 1 || released[0] != "/w/1" {
		t.Errorf("released %v, want the one workspace", released)
	}
	a := out.(delivery.BuildAnswer)
	if len(a.Artifacts) != 3 || a.Artifacts[1].Reference != "artifact-store://bundle" {
		t.Fatalf("answer %+v", a)
	}
}

// A build ask for another toolchain is refused, so its step ends refused and the asker reads why.
func TestRunAskRefusesAnotherToolchain(t *testing.T) {
	r := &recorder{fetch: map[string]any{"workspace": "/w"}}
	s := r.steps()
	s.Toolchain = func(context.Context) (delivery.ToolchainUsed, error) {
		return delivery.ToolchainUsed{Version: "go1.27", Recipe: "3"}, nil
	}
	_, err := RunAsk(context.Background(), s, ask(delivery.BuildJob{Module: "m", Path: ".", Fetch: map[string]any{"repository": "novox/x", "commit": runCommit},
		Artifacts: []delivery.AskArtifact{{Artifact: "bundle"}}, Toolchain: &delivery.ToolchainUsed{Version: "go1.26", Recipe: "3"}}))
	var ref *Refusal
	if !errors.As(err, &ref) || len(r.calls) != 0 {
		t.Fatalf("err %v, calls %v", err, r.calls)
	}
}

// 1887/A3, A5a, issue 1887 design limit 1: a check ask runs the levels of one check after one fetch: it digests the unit
// level, takes the kept verdicts, tests the packages whose tests changed first, and stops at the first failure, running
// no later level.
func TestRunAskChecksTheLevelsOfOneCheck(t *testing.T) {
	r := &recorder{
		fetch:   map[string]any{"workspace": "/w", "changed": []string{"pkg/b/b_test.go"}},
		digests: map[string]string{"x/pkg/a": "d-a", "x/pkg/b": "d-b", "x/pkg/k": "d-kept"},
		tests:   map[string]bool{"x/pkg/a": true, "x/pkg/b": false},
	}
	out, err := RunAsk(context.Background(), r.steps(), ask(delivery.CheckJob{Levels: []string{delivery.LevelUnit, delivery.LevelIntegration}, Kept: true,
		Runner: "workspace", RunnerWhen: "modules/mesh-build-go/", Fetch: map[string]any{"repository": "novox/x", "commit": runCommit, "base": runCommit}}))
	if err != nil {
		t.Fatal(err)
	}
	got := strings.Join(r.calls, "\n")
	want := `fetch {"base":"` + runCommit + `","commit":"` + runCommit + `","repository":"novox/x"}
digest {"level":"unit","workspace":"/w"}
test {"level":"unit","packages":["x/pkg/b"],"workspace":"/w"}`
	if got != want {
		t.Fatalf("calls:\n%s\nwant:\n%s", got, want)
	}
	a := out.(delivery.CheckAnswer)
	if len(a.Levels) != 1 {
		t.Fatalf("levels %+v, want the unit level alone", a.Levels)
	}
	u := a.Levels[0]
	if u.Level != delivery.LevelUnit || len(u.Kept) != 1 || u.Kept[0].Package != "x/pkg/k" || u.Kept[0].Tests != 7 || len(u.Tests) != 1 || u.Digest == nil {
		t.Fatalf("the unit level %+v", u)
	}
}

// ADR 0535 §2, §4: a merge that changes the build module's own code is judged by the candidate's runner: its digest says
// the candidate ran, and every package runs with nothing kept; an installed module that ignores the runner is planned as
// any other, the runner dropped. A digest that does not cover the fetch's siblings runs the level whole too.
func TestRunAskRunsWholeUnderTheRunnerOrWithoutTheSiblings(t *testing.T) {
	for _, tc := range []struct{ judged, want string }{
		{"candidate 999", `digest {"level":"unit","runner":"workspace","workspace":"/w"}
test {"level":"unit","runner":"workspace","workspace":"/w"}`},
		{"installed", `digest {"level":"unit","runner":"workspace","workspace":"/w"}`},
	} {
		r := &recorder{fetch: map[string]any{"workspace": "/w", "changed": []string{"modules/mesh-build-go/x.go"}},
			digests: map[string]string{"x/pkg/a": "d-kept"}, tests: map[string]bool{}}
		steps := r.steps()
		digest := steps.Digest
		steps.Digest = func(ctx context.Context, args map[string]any) (any, error) {
			_, _ = digest(ctx, args)
			return map[string]any{"level": "unit", "packages": r.digests, "judged_by": tc.judged}, nil
		}
		out, err := RunAsk(context.Background(), steps, ask(delivery.CheckJob{Levels: []string{delivery.LevelUnit}, Kept: true,
			Runner: "workspace", RunnerWhen: "modules/mesh-build-go/", Fetch: map[string]any{"repository": "novox/x", "commit": runCommit}}))
		if err != nil {
			t.Fatal(err)
		}
		if got := strings.Join(r.calls[1:], "\n"); got != tc.want {
			t.Errorf("judged by %s: calls\n%s\nwant\n%s", tc.judged, got, tc.want)
		}
		l := out.(delivery.CheckAnswer).Levels[0]
		if tc.judged == "installed" && (len(l.Kept) != 1 || l.Judged != "") {
			t.Errorf("an installed module's level %+v, want the kept verdict taken", l)
		}
		if tc.judged != "installed" && (len(l.Kept) != 0 || l.Digest != nil || l.Judged != tc.judged) {
			t.Errorf("the candidate's level %+v, want nothing kept and the program named", l)
		}
	}
	r := &recorder{fetch: map[string]any{"workspace": "/w"}, digests: map[string]string{"x/pkg/a": "d-kept"}, tests: map[string]bool{}}
	out, err := RunAsk(context.Background(), r.steps(), ask(delivery.CheckJob{Levels: []string{delivery.LevelUnit}, Kept: true,
		Fetch: map[string]any{"repository": "novox/x", "commit": runCommit, "beside": []any{map[string]any{"repository": "novox/mesh-sdk", "commit": runCommit}}}}))
	if err != nil {
		t.Fatal(err)
	}
	if l := out.(delivery.CheckAnswer).Levels[0]; len(l.Kept) != 0 || l.Digest != nil {
		t.Fatalf("a digest without the siblings kept %+v", l)
	}
}

// A Node check tests each module directory, the one whose tests changed first; a conflict ends the ask with the fetch
// alone, a verdict for the asker.
func TestRunAskChecksNodeModulesAndConflicts(t *testing.T) {
	r := &recorder{fetch: map[string]any{"workspace": "/w", "modules": []string{"a", "b"}, "changed": []string{"b/test/x.test.ts"}},
		tests: map[string]bool{"a": true, "b": true}}
	s := r.steps()
	s.Digest = nil
	if _, err := RunAsk(context.Background(), s, ask(delivery.CheckJob{Levels: []string{delivery.LevelUnit}, Fetch: map[string]any{"repository": "novox/x", "commit": runCommit}})); err != nil {
		t.Fatal(err)
	}
	if fmt.Sprint(r.calls[1:]) != `[test {"level":"unit","module":"b","workspace":"/w"} test {"level":"unit","module":"a","workspace":"/w"}]` {
		t.Fatalf("calls %v", r.calls)
	}
	r = &recorder{fetch: map[string]any{"workspace": "/w", "conflicts": []string{"go.mod"}}}
	out, err := RunAsk(context.Background(), r.steps(), ask(delivery.CheckJob{Levels: []string{delivery.LevelUnit}, Fetch: map[string]any{"repository": "novox/x", "commit": runCommit}}))
	if err != nil || len(r.calls) != 1 || len(out.(delivery.CheckAnswer).Levels) != 0 {
		t.Fatalf("a conflict: %v %v", err, r.calls)
	}
}