// tmctl is the TextMachine CLI: translate / report / status / export / build / redrive / manifest /
// backup / migrate / seed-lint / bank-apply (dispatchCommands).
// main.go — thin wiring (package №4): argument parsing — invocation.go,
// output renderers — render.go, .env — dotenv.go; here just the
// «parse → env → ctx → fetch → render» wiring and exit-code mapping.
package main

import (
	"context"
	"errors"
	"fmt"
	"io"
	"os"
	"os/signal"
	"path/filepath"
	"strings"
	"syscall"

	"textmachine/backend/internal/membank"
	"textmachine/backend/internal/obs"
	"textmachine/backend/internal/pipeline"
	"textmachine/backend/internal/store"
)

func main() {
	os.Exit(exitOf(os.Stderr, run))
}

// exitOf runs the command behind a recover so a panic of the MAIN goroutine leaves through the exit
// contract rather than the runtime's handler (obs.PanicError). Worker goroutines carry their own recover
// at the wave seam (pipeline.runWave); this covers everything else, from parsing to the renderers.
//
// `diag` is the diagnostics sink (main passes os.Stderr, tests a buffer) for the same reason
// parseInvocation takes one: what reaches stderr on a crash is the contract, so it is asserted rather
// than assumed. os.Exit is the CALLER's — it skips deferred functions, including this recover.
func exitOf(diag io.Writer, body func() error) (code int) {
	defer func() {
		if p := recover(); p != nil {
			err := obs.NewPanicError("tmctl", p)
			fmt.Fprintln(diag, "tmctl:", err)
			code = exitCode(err)
		}
	}()
	err := body()
	if err != nil {
		fmt.Fprintln(diag, "tmctl:", err)
	}
	return exitCode(err)
}

// The refusal band. A code in [refusalFirst, refusalLast] means the invocation was TURNED DOWN:
// nothing reached a provider, nothing was spent, no work needs rolling back and a retry is safe — and
// the particular number names why. «Nothing was written» is NOT the band's promise any more, it is a
// clause of the individual classes: exit 15 (write incomplete) legitimately answers with files on disk,
// and its report's `written_delta`/`written_rejects` carry which. A consumer keys a destructive action
// on a CLASS it knows, never on band membership (pipeline/refusal.go — the two-tier letter).
//
// It is a BAND and not a list because the vocabulary is the engine's and it will grow: a caller looks up
// the number, and a class this build of the caller has never heard of still lands in the band and reads
// as "refused" rather than as "failed". That difference is the whole of PD-196 — the platform's intake
// rejects a book as `source_unreadable` after five failures and deletes the upload, and every refusal
// used to arrive as the same exit 1, so an operator's typo in a hand-written book.yaml was one step from
// destroying a user's file. A new class is a new constant here and in pipeline.RefusalClass; no consumer
// has to enumerate them to stay safe.
const (
	refusalFirst = 10
	refusalLast  = 19

	exitConfigInvalid     = 10 // the configuration will not run: unreadable, unparseable, invalid, no key
	exitSourceUnreadable  = 11 // the BOOK's source cannot be read or decoded — the one class about the text
	exitProjectLocked     = 12 // another tmctl owns this project right now; come back later
	exitSchemaMismatch    = 13 // this project's schema is not this binary's: run `tmctl migrate` (row 174)
	exitDecisionsRejected = 14 // the decision document was read and declined; the USER re-decides (D39.156)
	exitWriteIncomplete   = 15 // the document was accepted and the write did not complete; the report says which file landed — re-send the same document
	exitBookIncomplete    = 16 // `build` refused to write a book with holes; the message lists them — finish the book, or ask for the marked copy with --partial
	exitRefusedOther      = 19 // a refusal class this build of tmctl has no number for
)

// refusalExit is the dictionary the band is read through.
var refusalExit = map[pipeline.RefusalClass]int{
	pipeline.RefusalBadConfig:         exitConfigInvalid,
	pipeline.RefusalSourceUnreadable:  exitSourceUnreadable,
	pipeline.RefusalProjectLocked:     exitProjectLocked,
	pipeline.RefusalSchemaMismatch:    exitSchemaMismatch,
	pipeline.RefusalDecisionsRejected: exitDecisionsRejected,
	pipeline.RefusalWriteIncomplete:   exitWriteIncomplete,
	pipeline.RefusalBookIncomplete:    exitBookIncomplete,
}

// exitCode maps a run() error onto the ratified shell contract (Milestone 2 / R1-FL-A):
//
//	0  clean
//	1  infra failure and everything else, including a flag-parse error and a recovered PANIC
//	   (*obs.PanicError, row 176)
//	2  completed-with-flags (acceptance allows N flags; the typed *pipeline.CompletedWithFlags,
//	   which survives %w-wraps via errors.As)
//	3  bank-mining signature stop (*pipeline.WaveSignatureStop — the run paused before the edit wave
//	   for owner sign; a DELIBERATE human-in-the-loop halt, not a crash)
//	4  ceiling halt (*pipeline.CeilingHalt — the book or day USD ceiling stopped the run)
//	5  graceful stop (SIGINT/SIGTERM was caught and the run wound down)
//	10-19 refusal band, see above
//
// 3 is DISTINCT from both 2 (flagged chunks) and 1 (crash) so exit-code automation can tell a
// sign-boundary pause from a real failure — a human sees the stderr text either way, but a script that
// shipped "translate && export" must NOT treat the pause as success (exit 0) nor as an infra crash.
//
// 4 and 5 exist for the same reason one level up, and they are money (row 165). A supervisor learns how
// a run ended from its exit code, so while a ceiling halt and a caught SIGTERM both mapped to 1 the
// platform recorded `failed` for both — for a stop its own contract calls `paused` and forbids calling
// `failed` (PD-113), and for the user's own stop and for an ordinary host reboot (PD-152). Since the
// ceiling argument is now set flush against the hold (PD-158), "the money ran out" and "the machine
// broke" were the same number at exactly the moment they became opposite facts.
//
// 5 reads a CANCELLED context because in tmctl the run context is cancelled by signal.NotifyContext and
// by nothing else (see run): a cancelled run is one somebody asked to stop. It is checked after the
// typed sentinels, so a run that reached its own terminal state before the signal keeps its own code.
func exitCode(err error) int {
	var flagged *pipeline.CompletedWithFlags
	var sigStop *pipeline.WaveSignatureStop
	var ceiling *pipeline.CeilingHalt
	var refusal *pipeline.Refusal
	var panicked *obs.PanicError
	switch {
	case err == nil:
		return 0
	case errors.As(err, &panicked):
		// A crash is 1, not a new number: both bands are frozen seams and a fresh code would be a word
		// added to a ratified dictionary. Checked FIRST so a panic cannot be read as one of the
		// deliberate stops below even if a layer joined it with one.
		return 1
	case errors.As(err, &sigStop):
		return 3
	case errors.As(err, &flagged):
		return 2
	case errors.As(err, &ceiling):
		return 4
	case errors.As(err, &refusal):
		if code, ok := refusalExit[refusal.Class]; ok {
			return code
		}
		return exitRefusedOther
	case errors.Is(err, context.Canceled):
		return 5
	default:
		return 1
	}
}

// traceID is the identity of this invocation: its log axis, its request_log column, and — since the
// event seam exists — the `engine_run_id` half of the ratified idempotency key (engine_run_id, seq).
//
// It is ACCEPTED from the environment (row 102) and minted only when none was given. A run the platform
// spawned should be ONE trace end to end, and letting the caller name it means the idempotency namespace
// of the stream is the caller's by construction rather than something it has to learn from a handshake
// (the reader's own comment anticipates exactly this). The environment and not a flag: argv is the one
// channel this zone keeps deliberately free of run identity (PD-99), and a supervisor already has an
// Env for the unit.
//
// A value it cannot use is REFUSED rather than trimmed into something else: an id is compared, joined
// and stored, so silently correcting it would make two runs share a namespace. The shape is what a log
// axis and a database key can both carry — printable, no spaces, bounded.
func traceID() string {
	v := os.Getenv("TM_TRACE_ID")
	if v == "" {
		return obs.NewTraceID()
	}
	if len(v) > 64 {
		fmt.Fprintf(os.Stderr, "tmctl: TM_TRACE_ID is %d characters (max 64) — minting one instead\n", len(v))
		return obs.NewTraceID()
	}
	for _, c := range v {
		if c <= ' ' || c > '~' {
			fmt.Fprintln(os.Stderr, "tmctl: TM_TRACE_ID must be printable ASCII without spaces — minting one instead")
			return obs.NewTraceID()
		}
	}
	return v
}

// dispatchCommands is the list the switch in run() dispatches, in usage order. It exists as ONE list
// because the usage line and the unknown-command hint were two hand-maintained copies of it, and the
// usage line fell three commands behind (row 176) while the hint stayed current.
var dispatchCommands = []string{
	"translate", "report", "status", "export", "build", "redrive", "manifest", "backup", "migrate", "seed-lint",
	"bank-apply",
}

func run() error {
	inv, err := parseInvocation(os.Args[1:], os.Stderr)
	if err != nil {
		return err
	}

	// KEY CHAIN, in precedence order. The DEPLOYMENT's file is first and therefore wins, because
	// loadDotEnv never overrides a variable that is already set: explicit beats convention, and the stand
	// books that pass no flag keep the behaviour they have always had. It is also the only link that can
	// FAIL — a file a caller named and that cannot be read is a deployment fault, not a missing option,
	// and the alternative is a paid run that dies at its first provider call (backlog row 211).
	if inv.keysFile != "" {
		if err := loadKeysFile(inv.keysFile, os.Stderr); err != nil {
			return pipeline.RefuseConfig(err)
		}
	}
	loadDotEnv(filepath.Join(filepath.Dir(inv.cfgPath), ".env"), os.Stderr)
	loadDotEnv(".env", os.Stderr)

	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()
	// LogBodies is decided once at admission (privacy by default): the content
	// of LLM exchanges reaches the logs only when LOG_LLM_BODIES=1 AND LOG_LEVEL=debug.
	ctx = obs.WithReqInfo(ctx, obs.ReqInfo{
		TraceID:   traceID(),
		LogBodies: os.Getenv("LOG_LLM_BODIES") == "1",
	})

	switch inv.cmd {
	case "translate":
		// F4 (row 83): back up + integrity-check the project DB before a paid run starts. This lives HERE
		// (the boevoy command dispatch), not in translate()/the Runner, so a fake-provider test that drives
		// those directly never triggers it — no provider-name discriminator needed.
		if err := preflightBackup(inv.cfgPath, os.Stdout); err != nil {
			return err
		}
		return translate(ctx, inv.cfgPath, inv.resnapshot, inv.acceptRebill, inv.verifyBank, inv.ceilingUSD, inv.maxUnits)
	case "report":
		return report(inv.cfgPath)
	case "status":
		return status(ctx, inv.cfgPath, inv.asJSON)
	case "export":
		return export(inv.cfgPath, inv.asPlaintext, inv.asPairs)
	case "build":
		return build(inv.cfgPath, inv.buildFormats, inv.buildOut, inv.buildPartial)
	case "redrive":
		// A dry-run redrive spends nothing and mutates nothing; only a real redrive re-attacks and re-bills.
		if !inv.sel.DryRun {
			if err := preflightBackup(inv.cfgPath, os.Stdout); err != nil {
				return err
			}
		}
		return redrive(ctx, inv.cfgPath, inv.resnapshot, inv.acceptRebill, inv.sel, inv.verifyBank, inv.ceilingUSD)
	case "manifest":
		return manifestCmd(inv.cfgPath, inv.asJSON)
	case "backup":
		return backupCmd(inv.cfgPath, os.Stdout)
	case "migrate":
		return migrateCmd(inv.cfgPath, os.Stdout)
	case "seed-lint":
		return seedLint(inv.seedPath)
	case "bank-apply":
		return bankApply(ctx, os.Stdout, inv.cfgPath, inv.decisionsPath, inv.dryRun)
	default:
		return fmt.Errorf("unknown command %q (want %s)", inv.cmd, strings.Join(dispatchCommands, "|"))
	}
}

// translate runs the book. The three money flags are ORTHOGONAL (D20.2-Q2 / row 145): --resnapshot
// grants permission to re-pin jobs onto the current config snapshot, --accept-rebill[=usd] consents to
// the AMOUNT that re-pin would re-pay, and --ceiling-usd replaces the BOOK ceiling for this process.
//
// ⚠ --ceiling-usd is NOT a per-run budget. The ledger admits against the book's CUMULATIVE spend
// (store/ledger.go: `bookTotal + estimate > BookUSD`, where bookTotal is committed+reserved across every
// run of the book), so the flag says "this book may reach $X while I am running", not "this run may
// spend $X". A caller that wants to grant an increment has to pass already-committed + increment, and a
// value below what the book has already spent denies the very first reservation.
//
// Over the book's consent threshold the run stops with the sum before reserving anything — a flag that
// names no money cannot carry a Р6 consent to a spend.
//
// --max-units is the FOURTH flag and the second CEILING, and it is orthogonal to --ceiling-usd in the way
// that matters most (D39.165 §1б): that one bounds the book's CUMULATIVE money, this one bounds THIS
// run's WORK, in output units — the granularity the manifest publishes and a purchase of chapters
// converts into exactly. Both can be in force; whichever binds first stops the run, and the two stops are
// different answers. Money stops the run in the middle of what it meant to do — exit 4, resumable, "add
// money". Volume means the run did precisely what was bought — exit 0, an ordinary completion, and the
// exit-code dictionary above is not touched. Which one stopped it is said in the run's report and its log
// (pipeline.VolumeStop), never by a new code: the platform reads an unknown exit code as a FAILURE, so a
// user who received exactly what they paid for would have been shown a service error.
func translate(ctx context.Context, cfgPath string, resnapshot bool, acceptRebill pipeline.RebillConsent, verifyBank bool, ceilingUSD float64, maxUnits int) error {
	r, err := pipeline.NewRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()
	r.Resnapshot = resnapshot
	r.AcceptRebill = acceptRebill
	r.VerifyBank = verifyBank
	r.CeilingUSD = ceilingUSD
	r.MaxUnits = maxUnits

	res, err := r.TranslateBook(ctx)
	if err != nil {
		// R1-FL-A: the bank-mining signature stop is a typed sentinel, not an infra failure — render the
		// operator's next steps to stdout (the bank table + the signature-map path + resume guidance) and
		// return it so main() maps it to the distinct exit code 3 (the Error() text also prints to stderr).
		var sigStop *pipeline.WaveSignatureStop
		if errors.As(err, &sigStop) {
			renderSignatureStop(os.Stdout, sigStop)
			// …and the MONEY (S17): the draft wave the pause sits behind is already paid for, and a stop
			// that reports zero about it leaves the operator guessing what the run has cost so far.
			if committed, reserved, lerr := r.Store.SpentUSD(r.Book.BookID); lerr == nil {
				fmt.Fprintf(os.Stdout, "Book ledger so far: committed=$%.6f reserved=$%.6f\n", committed, reserved)
			}
		}
		return err
	}
	return renderTranslate(os.Stdout, res, func() (float64, float64, error) {
		return r.Store.SpentUSD(res.BookID)
	})
}

// seedLint validates a glossary seed YAML (a manual seed or the emitted mined delta) through the REAL
// loadGlossarySeed fail-louds + the shared-key collision check (WS3). $0, no store, no provider keys — a
// pre-flight the operator runs on the mined delta before the W1.5 reseed. Prints "OK" on a clean seed.
func seedLint(seedPath string) error {
	if err := membank.SeedLint(seedPath); err != nil {
		return err
	}
	fmt.Fprintf(os.Stdout, "seed-lint OK: %s is loadable (0 fail-louds, 0 shared-key collisions)\n", seedPath)
	return nil
}

func report(cfgPath string) error {
	// Read-only ($0): no API keys required (D20.4 — a store audit must not demand provider keys).
	r, err := pipeline.NewReadOnlyRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()

	// Reads via callbacks (interleaved with printing, as historically): a read failure
	// mid-audit leaves the already-printed part on stdout (see renderReport).
	if err := renderReport(os.Stdout,
		func() ([]store.RequestLogView, error) { return r.Store.RequestLogRows(r.Book.BookID) },
		func() ([]store.ChunkStatus, error) { return r.Store.ChunkStatusesForBook(r.Book.BookID) },
		func() ([]store.RetrievalState, error) { return r.Store.RetrievalStatesForBook(r.Book.BookID) },
		func() (float64, float64, error) { return r.Store.SpentUSD(r.Book.BookID) }); err != nil {
		return err
	}
	// Per-run quality-report (D39 layer 5): aggregate the deterministic quality signals into a readable
	// summary — the "telemetry from day one" the owner asked for (H5). Read-only ($0), never a gate.
	q, err := r.QualityReport()
	if err != nil {
		return err
	}
	return renderQuality(os.Stdout, q)
}

// export prints the READ-ONLY export projection (D39 layer 6 / D39.2-open №1): every chunk's FINAL
// export text EXACTLY by prod semantics (final_hash → checkpoint → exportNormalize), so the polygon
// extractor / reader-samples read the SAME bytes the backend ships instead of the raw checkpoint. Like
// report/status it is $0 and needs no provider keys (D20.4 — an audit surface must not demand keys).
// Default output is stable JSON (the machine surface); --plaintext emits the human concatenation.
func export(cfgPath string, asPlaintext, asPairs bool) error {
	r, err := pipeline.NewReadOnlyRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()

	exp, err := r.Export(asPairs)
	if err != nil {
		return err
	}
	return renderExport(os.Stdout, exp, asPlaintext)
}

// build writes the READER's copy of the book (backlog row 236): EPUB and/or plain text from the same
// export projection `export` prints, beside the project database (pipeline.BuildBook). $0 and key-less
// like export — it reads the store and writes a file; no provider is called. A book with any hole is
// refused (exit 16, the holes listed) unless --partial asks for the marked copy. Its own verb rather than a
// flag on `export`: `export` is a pure read whose stdout IS its output, and a command that writes files
// beside the database is a different thing to script around (the `manifest` precedent).
func build(cfgPath string, formats []string, out string, partial bool) error {
	r, err := pipeline.NewReadOnlyRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()

	rep, err := r.BuildBook(pipeline.BuildOptions{Formats: formats, Out: out, Partial: partial})
	if err != nil {
		return err
	}
	return renderBuild(os.Stdout, rep)
}

// status prints the READ-ONLY progress projection (D15.3): 0 LLM, 0 replay. --json emits the
// StatusReport with stable disposition/flag_reason enums for CI/IDE; the default is a human
// dashboard (unit counts, per-chapter quality passports, money, secondary ETA). BOTH modes exit 2
// (completed-with-flags) when flagged>0 (minor 1d — --json used to always exit 0), so a consumer
// never reads a clean 0 over a book that still needs attention.
func status(ctx context.Context, cfgPath string, asJSON bool) error {
	// Read-only ($0): no API keys required (D20.4 — a progress projection must not demand keys).
	r, err := pipeline.NewReadOnlyRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()

	rep, err := r.Status(ctx)
	if err != nil {
		return err
	}
	if asJSON {
		return renderStatusJSON(os.Stdout, rep)
	}
	return renderStatusHuman(os.Stdout, rep, cfgPath)
}

// manifestCmd rebuilds and persists the book's chapter/chunk manifest (backlog row 100). $0 and key-less
// like the other read commands: it ingests + cuts the source and writes a sidecar beside the project DB —
// no LLM, no provider key, no wave.
//
// It opens the store exactly as `status` does (NewReadOnlyRunner): read-only, no flock — EXCEPT on the
// first touch of a project, where that path falls back to a full Open and therefore CREATES and migrates
// the database. That is the state this command is most often run in ("parsed, never run"), so the
// side effect is the common case rather than the corner one, and it is the same one `status` has always
// had. It also needs the project directory to be writable, unlike status/report/export.
//
// It exists because the manifest is needed BEFORE any run: a book that has been accepted and cut but
// never translated still has a chapter tree, and every other producer of that structure is a paid path.
// A translate rewrites the manifest itself (bookrun.go), so this command is for the not-yet-run case and
// for refreshing the artifact by hand after a source edit.
func manifestCmd(cfgPath string, asJSON bool) error {
	r, err := pipeline.NewReadOnlyRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()

	m, err := r.BuildAndPersistManifest()
	if err != nil {
		return err
	}
	return renderManifest(os.Stdout, m, r.ManifestPath(), asJSON)
}

// redrive re-attacks the FLAGGED chunks matching the selector (D15.3): it resets their terminal
// flag (chunk_status + checkpoints of the flagged/skipped stages) and re-runs the durable loop
// with a FRESH retry/escalation budget, never touching DispOK work. On --dry-run it only reports
// the plan. Redrive-calls bill normally; money already spent on the discarded attempts stays
// committed (honest). By default it requires the current config to render the SAME snapshot the
// flagged rows carry (else it fails loud); passing --resnapshot wires r.Resnapshot so Redrive skips
// that drift guard and accepts the re-pin/re-pay explicitly (D20.4: the flag used to be parsed but
// silently ignored — Redrive already honoured r.Resnapshot, only the CLI never set it).
// --accept-rebill[=usd] is the separate consent to the AMOUNT such a re-pin re-pays (D20.2-Q2): over
// the threshold Redrive refuses BEFORE its destructive reset, so the flag telemetry survives a refusal.
// --ceiling-usd applies here for the same reason it applies to translate: a redrive re-attacks flagged
// chunks with real provider calls, so leaving it on the book's ceiling alone would be a hole in exactly
// the surface row 145 exists to close.
func redrive(ctx context.Context, cfgPath string, resnapshot bool, acceptRebill pipeline.RebillConsent, sel pipeline.RedriveSelector, verifyBank bool, ceilingUSD float64) error {
	r, err := pipeline.NewRunner(cfgPath, obs.NewLogger())
	if err != nil {
		return err
	}
	defer r.Close()
	r.Resnapshot = resnapshot
	r.AcceptRebill = acceptRebill
	r.VerifyBank = verifyBank
	r.CeilingUSD = ceilingUSD

	summary, res, err := r.Redrive(ctx, sel)
	if err != nil {
		// A redrive can hit the bank-mining stop too (it re-runs the durable loop), and its reset is
		// DESTRUCTIVE and already done by then — so a bare error text left the operator with reset rows,
		// exit 3 and no idea why (S17). Print the same banner translate does.
		var sigStop *pipeline.WaveSignatureStop
		if errors.As(err, &sigStop) {
			renderSignatureStop(os.Stdout, sigStop)
		}
		return err
	}
	return renderRedrive(os.Stdout, r.Book.BookID, summary, res, func() (float64, float64, error) {
		return r.Store.SpentUSD(r.Book.BookID)
	})
}