package keymap

import (
	"testing"

	uv "github.com/charmbracelet/ultraviolet"
)

func TestParseEvents(t *testing.T) {
	cases := []struct {
		name string
		want uv.KeyPressEvent
	}{
		{"Enter", uv.KeyPressEvent{Code: uv.KeyEnter}},
		{"enter", uv.KeyPressEvent{Code: uv.KeyEnter}},
		{"Escape", uv.KeyPressEvent{Code: uv.KeyEscape}},
		{"Esc", uv.KeyPressEvent{Code: uv.KeyEscape}},
		{"Tab", uv.KeyPressEvent{Code: uv.KeyTab}},
		{"BTab", uv.KeyPressEvent{Code: uv.KeyTab, Mod: uv.ModShift}},
		{"S-Tab", uv.KeyPressEvent{Code: uv.KeyTab, Mod: uv.ModShift}},
		{"Backspace", uv.KeyPressEvent{Code: uv.KeyBackspace}},
		{"Space", uv.KeyPressEvent{Code: ' '}},
		{"Up", uv.KeyPressEvent{Code: uv.KeyUp}},
		{"Down", uv.KeyPressEvent{Code: uv.KeyDown}},
		{"Left", uv.KeyPressEvent{Code: uv.KeyLeft}},
		{"Right", uv.KeyPressEvent{Code: uv.KeyRight}},
		{"Home", uv.KeyPressEvent{Code: uv.KeyHome}},
		{"End", uv.KeyPressEvent{Code: uv.KeyEnd}},
		{"PgUp", uv.KeyPressEvent{Code: uv.KeyPgUp}},
		{"PageDown", uv.KeyPressEvent{Code: uv.KeyPgDown}},
		{"Insert", uv.KeyPressEvent{Code: uv.KeyInsert}},
		{"Delete", uv.KeyPressEvent{Code: uv.KeyDelete}},
		{"F1", uv.KeyPressEvent{Code: uv.KeyF1}},
		{"F12", uv.KeyPressEvent{Code: uv.KeyF12}},
		{"a", uv.KeyPressEvent{Code: 'a'}},
		{"Z", uv.KeyPressEvent{Code: 'Z'}},
		{"%", uv.KeyPressEvent{Code: '%'}},
		{"C-c", uv.KeyPressEvent{Code: 'c', Mod: uv.ModCtrl}},
		{"C-C", uv.KeyPressEvent{Code: 'c', Mod: uv.ModCtrl}}, // normalized to lowercase
		{"C-Space", uv.KeyPressEvent{Code: ' ', Mod: uv.ModCtrl}},
		{"C-[", uv.KeyPressEvent{Code: '[', Mod: uv.ModCtrl}},
		{"C-]", uv.KeyPressEvent{Code: ']', Mod: uv.ModCtrl}},
		{"C-_", uv.KeyPressEvent{Code: '_', Mod: uv.ModCtrl}},
		{"M-x", uv.KeyPressEvent{Code: 'x', Mod: uv.ModAlt}},
		{"M-Enter", uv.KeyPressEvent{Code: uv.KeyEnter, Mod: uv.ModAlt}},
		{"M-Escape", uv.KeyPressEvent{Code: uv.KeyEscape, Mod: uv.ModAlt}},
		{"C-M-x", uv.KeyPressEvent{Code: 'x', Mod: uv.ModCtrl | uv.ModAlt}},
		{"M-C-x", uv.KeyPressEvent{Code: 'x', Mod: uv.ModCtrl | uv.ModAlt}},
		{"S-a", uv.KeyPressEvent{Code: 'A'}},
		{"C-S-a", uv.KeyPressEvent{Code: 'a', Mod: uv.ModCtrl}}, // shift folds into the letter, ctrl re-lowers
		{"-", uv.KeyPressEvent{Code: '-'}},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			k, err := Parse(tc.name)
			if err != nil {
				t.Fatalf("Parse(%q): %v", tc.name, err)
			}
			ev, ok := k.Event()
			if !ok {
				raw, _ := k.Raw()
				t.Fatalf("Parse(%q) produced raw bytes %q, want event", tc.name, raw)
			}
			if ev != tc.want {
				t.Errorf("Parse(%q) = %+v, want %+v", tc.name, ev, tc.want)
			}
		})
	}
}

// Modified special keys have no vt-encoder support and must come out as
// pre-encoded xterm sequences: CSI 1;m<ch> and CSI n;m~ with
// m = 1 + Shift(1) + Alt(2) + Ctrl(4).
func TestParseModifiedSpecials(t *testing.T) {
	cases := []struct {
		name string
		want string
	}{
		{"C-Up", "\x1b[1;5A"},
		{"S-Up", "\x1b[1;2A"},
		{"M-Up", "\x1b[1;3A"},
		{"C-S-Up", "\x1b[1;6A"},
		{"C-M-Up", "\x1b[1;7A"},
		{"C-M-S-Up", "\x1b[1;8A"},
		{"C-Down", "\x1b[1;5B"},
		{"C-Right", "\x1b[1;5C"},
		{"C-Left", "\x1b[1;5D"},
		{"C-Home", "\x1b[1;5H"},
		{"S-End", "\x1b[1;2F"},
		{"C-F1", "\x1b[1;5P"},
		{"S-F4", "\x1b[1;2S"},
		{"C-Delete", "\x1b[3;5~"},
		{"S-Insert", "\x1b[2;2~"},
		{"M-PgUp", "\x1b[5;3~"},
		{"C-PgDn", "\x1b[6;5~"},
		{"C-F5", "\x1b[15;5~"},
		{"S-F12", "\x1b[24;2~"},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			k, err := Parse(tc.name)
			if err != nil {
				t.Fatalf("Parse(%q): %v", tc.name, err)
			}
			raw, ok := k.Raw()
			if !ok {
				ev, _ := k.Event()
				t.Fatalf("Parse(%q) produced event %+v, want raw bytes", tc.name, ev)
			}
			if string(raw) != tc.want {
				t.Errorf("Parse(%q) = %q, want %q", tc.name, raw, tc.want)
			}
		})
	}
}

func TestParseErrors(t *testing.T) {
	for _, name := range []string{
		"",        // empty
		"NoSuch",  // unknown named key
		"C-",      // dangling modifier
		"X-a",     // bad modifier letter
		"C-1",     // no control character for digits
		"C--",     // no control character for dash
		"S-5",     // shift is only meaningful on letters
		"C-Enter", // no escape sequence exists
		"ab",      // multi-rune non-name
	} {
		t.Run("bad:"+name, func(t *testing.T) {
			if k, err := Parse(name); err == nil {
				t.Errorf("Parse(%q) succeeded (%+v), want error", name, k)
			}
		})
	}
}