package cli

import (
	"path/filepath"
	"testing"
)

func TestParseArgs(t *testing.T) {
	tests := []struct {
		name    string
		args    []string
		action  Action
		wantVal map[string]string
		uris    []string
	}{
		{"short attached", []string{"-x16", "https://e.com"}, Run, map[string]string{"max-connection-per-server": "16"}, []string{"https://e.com"}},
		{"long equals + bool", []string{"--split=8", "-c", "u"}, Run, map[string]string{"split": "8", "continue": "true"}, []string{"u"}},
		{"long separate value", []string{"--out", "f.bin", "u"}, Run, map[string]string{"out": "f.bin"}, []string{"u"}},
		{"bool bundle", []string{"-cq", "u"}, Run, map[string]string{"continue": "true", "quiet": "true"}, []string{"u"}},
		{"repeatable header", []string{"--header", "A: 1", "--header", "B: 2", "u"}, Run, map[string]string{"header": "A: 1\nB: 2"}, []string{"u"}},
		{"two uris", []string{"a", "b"}, Run, map[string]string{}, []string{"a", "b"}},
		{"permute flag after uri", []string{"u", "--split=8"}, Run, map[string]string{"split": "8"}, []string{"u"}},
		{"permute interleaved", []string{"a", "-c", "b", "--quiet"}, Run, map[string]string{"continue": "true", "quiet": "true"}, []string{"a", "b"}},
		{"dash dash terminator", []string{"--split=8", "--", "--not-a-flag", "u"}, Run, map[string]string{"split": "8"}, []string{"--not-a-flag", "u"}},
		{"long int + magnet uri", []string{"--bt-stop-timeout=120", "magnet:x"}, Run, map[string]string{"bt-stop-timeout": "120"}, []string{"magnet:x"}},
		{"help", []string{"--help"}, ShowHelp, nil, nil},
		{"help short", []string{"-h"}, ShowHelp, nil, nil},
		{"version", []string{"-v"}, ShowVersion, nil, nil},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			vals, uris, action, _, err := parseArgs(tc.args)
			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}
			if action != tc.action {
				t.Fatalf("action = %v, want %v", action, tc.action)
			}
			if tc.action != Run {
				return
			}
			for k, want := range tc.wantVal {
				if vals[k] != want {
					t.Errorf("vals[%q] = %q, want %q", k, vals[k], want)
				}
			}
			if len(uris) != len(tc.uris) {
				t.Fatalf("uris = %v, want %v", uris, tc.uris)
			}
			for i := range uris {
				if uris[i] != tc.uris[i] {
					t.Errorf("uris[%d] = %q, want %q", i, uris[i], tc.uris[i])
				}
			}
		})
	}
}

func TestParseArgsErrors(t *testing.T) {
	for _, args := range [][]string{
		{"--unknown-flag"},
		{"-Q"},    // -Q is not a defined short flag
		{"--out"}, // missing value
	} {
		if _, _, _, _, err := parseArgs(args); err == nil {
			t.Errorf("parseArgs(%v) = nil error, want error", args)
		}
	}
}

func TestParseSize(t *testing.T) {
	tests := []struct {
		in   string
		want int64
	}{
		{"", 0},
		{"100", 100},
		{"512K", 512 << 10},
		{"20M", 20 << 20},
		{"1024M", 1 << 30}, // there is no G unit; the 1G bound is typed as 1024M
		{"1Mi", 1 << 20},   // the first K/M is taken and the rest discarded
		{"10MB", 10 << 20},
		{"2k", 2 << 10},
	}
	for _, tc := range tests {
		got, err := parseSize(tc.in)
		if err != nil {
			t.Errorf("parseSize(%q) error: %v", tc.in, err)
			continue
		}
		if got != tc.want {
			t.Errorf("parseSize(%q) = %d, want %d", tc.in, got, tc.want)
		}
	}
}

func TestValidateRange(t *testing.T) {
	x := byLong["max-connection-per-server"]
	if err := validate(x, "16"); err != nil {
		t.Errorf("validate 16: %v", err)
	}
	if err := validate(x, "99"); err == nil {
		t.Errorf("validate 99: want out-of-range error")
	}
	a := byLong["file-allocation"]
	if err := validate(a, "bogus"); err == nil {
		t.Errorf("validate enum bogus: want error")
	}
}

func TestValidateIntFloor(t *testing.T) {
	// Min:0 now enforces a floor of 0: negatives are rejected.
	m := byLong["max-tries"] // Min 0, "0 = unlimited" runtime meaning preserved
	if err := validate(m, "0"); err != nil {
		t.Errorf("validate max-tries 0: %v, want nil (0 stays a valid input)", err)
	}
	if err := validate(m, "-1"); err == nil {
		t.Errorf("validate max-tries -1: want below-minimum error")
	}
}

func TestValidateFloatNonNegative(t *testing.T) {
	// Float options (seed-time, seed-ratio) reject negatives: a negative
	// SeedTime would fire the seed timer immediately and a negative SeedRatio
	// is silently ignored, so neither is a meaningful input.
	for _, name := range []string{"seed-ratio", "seed-time"} {
		o := byLong[name]
		if err := validate(o, "-1"); err == nil {
			t.Errorf("validate %s -1: want below-minimum error", name)
		}
		if err := validate(o, "0"); err != nil {
			t.Errorf("validate %s 0: %v, want nil", name, err)
		}
		if err := validate(o, "1.5"); err != nil {
			t.Errorf("validate %s 1.5: %v, want nil", name, err)
		}
	}
}

func TestValidateBool(t *testing.T) {
	b := byLong["enable-dht"]
	// Only literal true/false are accepted (case-sensitive), with surrounding
	// whitespace trimmed.
	for _, ok := range []string{"true", "false", " true ", "false\t"} {
		if err := validate(b, ok); err != nil {
			t.Errorf("validate bool %q: %v", ok, err)
		}
	}
	// The invented spellings and any case variant must now fail.
	for _, bad := range []string{"yes", "no", "1", "0", "on", "off", "flase",
		"True", "TRUE", "tRuE", "False", "FALSE"} {
		if err := validate(b, bad); err == nil {
			t.Errorf("validate bool %q: want error (only true/false accepted)", bad)
		}
	}
}

func TestValidateSizeBounds(t *testing.T) {
	k := byLong["min-split-size"] // 1M..1024M (no G unit)
	if err := validate(k, "20M"); err != nil {
		t.Errorf("validate min-split-size 20M: %v", err)
	}
	if err := validate(k, "512K"); err == nil {
		t.Errorf("validate min-split-size 512K: want below-minimum error")
	}
	// 1025M exceeds the 1<<30 cap and still parses, so it tests the bounds path
	// (where "2G" would have failed earlier as an unknown unit).
	if err := validate(k, "1025M"); err == nil {
		t.Errorf("validate min-split-size 1025M: want above-maximum error")
	}
}

func TestParseSizeNegative(t *testing.T) {
	if _, err := parseSize("-1"); err == nil {
		t.Errorf("parseSize(-1): want error (size parsing rejects negative values)")
	}
	if _, err := parseSize("-5M"); err == nil {
		t.Errorf("parseSize(-5M): want error")
	}
}

// size parsing knows only K and M; a "G" suffix is not a unit and must be
// rejected rather than silently treated as 2^30.
func TestParseSizeNoGigaUnit(t *testing.T) {
	for _, in := range []string{"1G", "1g", "1Gi", "5GB"} {
		if _, err := parseSize(in); err == nil {
			t.Errorf("parseSize(%q): want error (no G unit)", in)
		}
	}
}

func TestExplicitConfMissingFatal(t *testing.T) {
	missing := filepath.Join(t.TempDir(), "no-such-file.conf")
	// Default (non-explicit) missing path is silently ignored.
	if err := applyConfig(newOptions(), missing, false); err != nil {
		t.Errorf("applyConfig default missing: %v, want nil", err)
	}
	// Explicit missing path is fatal.
	if err := applyConfig(newOptions(), missing, true); err == nil {
		t.Errorf("applyConfig explicit missing: want error")
	}
}

func TestOptionsGetters(t *testing.T) {
	o := newOptions()
	o.vals["split"] = "8"
	o.vals["min-split-size"] = "20M"
	o.vals["continue"] = "true"
	o.vals["seed-ratio"] = "1.5"
	if o.Int("split") != 8 {
		t.Errorf("Int split = %d", o.Int("split"))
	}
	if o.Size("min-split-size") != 20<<20 {
		t.Errorf("Size min-split-size = %d", o.Size("min-split-size"))
	}
	if !o.Bool("continue") {
		t.Errorf("Bool continue = false")
	}
	if o.Float("seed-ratio") != 1.5 {
		t.Errorf("Float seed-ratio = %v", o.Float("seed-ratio"))
	}
}