// Copyright 2015 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.

package mysql

import "unicode"

// CharsetNameToID maps charset name to its default collation ID.
func CharsetNameToID(charset string) uint8 {
	// Use quick path for TiDB to avoid access CharsetIDs map
	// "SHOW CHARACTER SET;" to see all the supported character sets.
	if charset == "utf8mb4" {
		return UTF8MB4DefaultCollationID
	} else if charset == "binary" {
		return BinaryDefaultCollationID
	} else if charset == "utf8" {
		return UTF8DefaultCollationID
	} else if charset == "ascii" {
		return ASCIIDefaultCollationID
	} else if charset == "latin1" {
		return Latin1DefaultCollationID
	} else {
		return CharsetIDs[charset]
	}
}

// CharsetIDs maps charset name to its default collation ID.
var CharsetIDs = map[string]uint8{
	"big5":     1,
	"dec8":     3,
	"cp850":    4,
	"hp8":      6,
	"koi8r":    7,
	"latin1":   Latin1DefaultCollationID,
	"latin2":   9,
	"swe7":     10,
	"ascii":    ASCIIDefaultCollationID,
	"ujis":     12,
	"sjis":     13,
	"hebrew":   16,
	"tis620":   18,
	"euckr":    19,
	"koi8u":    22,
	"gb2312":   24,
	"greek":    25,
	"cp1250":   26,
	"gbk":      28,
	"latin5":   30,
	"armscii8": 32,
	"utf8":     UTF8DefaultCollationID,
	"ucs2":     35,
	"cp866":    36,
	"keybcs2":  37,
	"macce":    38,
	"macroman": 39,
	"cp852":    40,
	"latin7":   41,
	"utf8mb4":  UTF8MB4DefaultCollationID,
	"cp1251":   51,
	"utf16":    54,
	"utf16le":  56,
	"cp1256":   57,
	"cp1257":   59,
	"utf32":    60,
	"binary":   BinaryDefaultCollationID,
	"geostd8":  92,
	"cp932":    95,
	"eucjpms":  97,
}

// Charsets maps charset name to its default collation name.
var Charsets = map[string]string{
	"big5":     "big5_chinese_ci",
	"dec8":     "dec8_swedish_ci",
	"cp850":    "cp850_general_ci",
	"hp8":      "hp8_english_ci",
	"koi8r":    "koi8r_general_ci",
	"latin1":   "latin1_bin",
	"latin2":   "latin2_general_ci",
	"swe7":     "swe7_swedish_ci",
	"ascii":    "ascii_bin",
	"ujis":     "ujis_japanese_ci",
	"sjis":     "sjis_japanese_ci",
	"hebrew":   "hebrew_general_ci",
	"tis620":   "tis620_thai_ci",
	"euckr":    "euckr_korean_ci",
	"koi8u":    "koi8u_general_ci",
	"gb2312":   "gb2312_chinese_ci",
	"greek":    "greek_general_ci",
	"cp1250":   "cp1250_general_ci",
	"gbk":      "gbk_chinese_ci",
	"latin5":   "latin5_turkish_ci",
	"armscii8": "armscii8_general_ci",
	"utf8":     "utf8_bin",
	"ucs2":     "ucs2_general_ci",
	"cp866":    "cp866_general_ci",
	"keybcs2":  "keybcs2_general_ci",
	"macce":    "macce_general_ci",
	"macroman": "macroman_general_ci",
	"cp852":    "cp852_general_ci",
	"latin7":   "latin7_general_ci",
	"utf8mb4":  "utf8mb4_bin",
	"cp1251":   "cp1251_general_ci",
	"utf16":    "utf16_general_ci",
	"utf16le":  "utf16le_general_ci",
	"cp1256":   "cp1256_general_ci",
	"cp1257":   "cp1257_general_ci",
	"utf32":    "utf32_general_ci",
	"binary":   "binary",
	"geostd8":  "geostd8_general_ci",
	"cp932":    "cp932_japanese_ci",
	"eucjpms":  "eucjpms_japanese_ci",
}

// Collations maps MySQL collation ID to its name.
var Collations = map[uint8]string{
	1:   "big5_chinese_ci",
	2:   "latin2_czech_cs",
	3:   "dec8_swedish_ci",
	4:   "cp850_general_ci",
	5:   "latin1_german1_ci",
	6:   "hp8_english_ci",
	7:   "koi8r_general_ci",
	8:   "latin1_swedish_ci",
	9:   "latin2_general_ci",
	10:  "swe7_swedish_ci",
	11:  "ascii_general_ci",
	12:  "ujis_japanese_ci",
	13:  "sjis_japanese_ci",
	14:  "cp1251_bulgarian_ci",
	15:  "latin1_danish_ci",
	16:  "hebrew_general_ci",
	18:  "tis620_thai_ci",
	19:  "euckr_korean_ci",
	20:  "latin7_estonian_cs",
	21:  "latin2_hungarian_ci",
	22:  "koi8u_general_ci",
	23:  "cp1251_ukrainian_ci",
	24:  "gb2312_chinese_ci",
	25:  "greek_general_ci",
	26:  "cp1250_general_ci",
	27:  "latin2_croatian_ci",
	28:  "gbk_chinese_ci",
	29:  "cp1257_lithuanian_ci",
	30:  "latin5_turkish_ci",
	31:  "latin1_german2_ci",
	32:  "armscii8_general_ci",
	33:  "utf8_general_ci",
	34:  "cp1250_czech_cs",
	35:  "ucs2_general_ci",
	36:  "cp866_general_ci",
	37:  "keybcs2_general_ci",
	38:  "macce_general_ci",
	39:  "macroman_general_ci",
	40:  "cp852_general_ci",
	41:  "latin7_general_ci",
	42:  "latin7_general_cs",
	43:  "macce_bin",
	44:  "cp1250_croatian_ci",
	45:  "utf8mb4_general_ci",
	46:  "utf8mb4_bin",
	47:  "latin1_bin",
	48:  "latin1_general_ci",
	49:  "latin1_general_cs",
	50:  "cp1251_bin",
	51:  "cp1251_general_ci",
	52:  "cp1251_general_cs",
	53:  "macroman_bin",
	54:  "utf16_general_ci",
	55:  "utf16_bin",
	56:  "utf16le_general_ci",
	57:  "cp1256_general_ci",
	58:  "cp1257_bin",
	59:  "cp1257_general_ci",
	60:  "utf32_general_ci",
	61:  "utf32_bin",
	62:  "utf16le_bin",
	63:  "binary",
	64:  "armscii8_bin",
	65:  "ascii_bin",
	66:  "cp1250_bin",
	67:  "cp1256_bin",
	68:  "cp866_bin",
	69:  "dec8_bin",
	70:  "greek_bin",
	71:  "hebrew_bin",
	72:  "hp8_bin",
	73:  "keybcs2_bin",
	74:  "koi8r_bin",
	75:  "koi8u_bin",
	77:  "latin2_bin",
	78:  "latin5_bin",
	79:  "latin7_bin",
	80:  "cp850_bin",
	81:  "cp852_bin",
	82:  "swe7_bin",
	83:  "utf8_bin",
	84:  "big5_bin",
	85:  "euckr_bin",
	86:  "gb2312_bin",
	87:  "gbk_bin",
	88:  "sjis_bin",
	89:  "tis620_bin",
	90:  "ucs2_bin",
	91:  "ujis_bin",
	92:  "geostd8_general_ci",
	93:  "geostd8_bin",
	94:  "latin1_spanish_ci",
	95:  "cp932_japanese_ci",
	96:  "cp932_bin",
	97:  "eucjpms_japanese_ci",
	98:  "eucjpms_bin",
	99:  "cp1250_polish_ci",
	101: "utf16_unicode_ci",
	102: "utf16_icelandic_ci",
	103: "utf16_latvian_ci",
	104: "utf16_romanian_ci",
	105: "utf16_slovenian_ci",
	106: "utf16_polish_ci",
	107: "utf16_estonian_ci",
	108: "utf16_spanish_ci",
	109: "utf16_swedish_ci",
	110: "utf16_turkish_ci",
	111: "utf16_czech_ci",
	112: "utf16_danish_ci",
	113: "utf16_lithuanian_ci",
	114: "utf16_slovak_ci",
	115: "utf16_spanish2_ci",
	116: "utf16_roman_ci",
	117: "utf16_persian_ci",
	118: "utf16_esperanto_ci",
	119: "utf16_hungarian_ci",
	120: "utf16_sinhala_ci",
	121: "utf16_german2_ci",
	122: "utf16_croatian_ci",
	123: "utf16_unicode_520_ci",
	124: "utf16_vietnamese_ci",
	128: "ucs2_unicode_ci",
	129: "ucs2_icelandic_ci",
	130: "ucs2_latvian_ci",
	131: "ucs2_romanian_ci",
	132: "ucs2_slovenian_ci",
	133: "ucs2_polish_ci",
	134: "ucs2_estonian_ci",
	135: "ucs2_spanish_ci",
	136: "ucs2_swedish_ci",
	137: "ucs2_turkish_ci",
	138: "ucs2_czech_ci",
	139: "ucs2_danish_ci",
	140: "ucs2_lithuanian_ci",
	141: "ucs2_slovak_ci",
	142: "ucs2_spanish2_ci",
	143: "ucs2_roman_ci",
	144: "ucs2_persian_ci",
	145: "ucs2_esperanto_ci",
	146: "ucs2_hungarian_ci",
	147: "ucs2_sinhala_ci",
	148: "ucs2_german2_ci",
	149: "ucs2_croatian_ci",
	150: "ucs2_unicode_520_ci",
	151: "ucs2_vietnamese_ci",
	159: "ucs2_general_mysql500_ci",
	160: "utf32_unicode_ci",
	161: "utf32_icelandic_ci",
	162: "utf32_latvian_ci",
	163: "utf32_romanian_ci",
	164: "utf32_slovenian_ci",
	165: "utf32_polish_ci",
	166: "utf32_estonian_ci",
	167: "utf32_spanish_ci",
	168: "utf32_swedish_ci",
	169: "utf32_turkish_ci",
	170: "utf32_czech_ci",
	171: "utf32_danish_ci",
	172: "utf32_lithuanian_ci",
	173: "utf32_slovak_ci",
	174: "utf32_spanish2_ci",
	175: "utf32_roman_ci",
	176: "utf32_persian_ci",
	177: "utf32_esperanto_ci",
	178: "utf32_hungarian_ci",
	179: "utf32_sinhala_ci",
	180: "utf32_german2_ci",
	181: "utf32_croatian_ci",
	182: "utf32_unicode_520_ci",
	183: "utf32_vietnamese_ci",
	192: "utf8_unicode_ci",
	193: "utf8_icelandic_ci",
	194: "utf8_latvian_ci",
	195: "utf8_romanian_ci",
	196: "utf8_slovenian_ci",
	197: "utf8_polish_ci",
	198: "utf8_estonian_ci",
	199: "utf8_spanish_ci",
	200: "utf8_swedish_ci",
	201: "utf8_turkish_ci",
	202: "utf8_czech_ci",
	203: "utf8_danish_ci",
	204: "utf8_lithuanian_ci",
	205: "utf8_slovak_ci",
	206: "utf8_spanish2_ci",
	207: "utf8_roman_ci",
	208: "utf8_persian_ci",
	209: "utf8_esperanto_ci",
	210: "utf8_hungarian_ci",
	211: "utf8_sinhala_ci",
	212: "utf8_german2_ci",
	213: "utf8_croatian_ci",
	214: "utf8_unicode_520_ci",
	215: "utf8_vietnamese_ci",
	223: "utf8_general_mysql500_ci",
	224: "utf8mb4_unicode_ci",
	225: "utf8mb4_icelandic_ci",
	226: "utf8mb4_latvian_ci",
	227: "utf8mb4_romanian_ci",
	228: "utf8mb4_slovenian_ci",
	229: "utf8mb4_polish_ci",
	230: "utf8mb4_estonian_ci",
	231: "utf8mb4_spanish_ci",
	232: "utf8mb4_swedish_ci",
	233: "utf8mb4_turkish_ci",
	234: "utf8mb4_czech_ci",
	235: "utf8mb4_danish_ci",
	236: "utf8mb4_lithuanian_ci",
	237: "utf8mb4_slovak_ci",
	238: "utf8mb4_spanish2_ci",
	239: "utf8mb4_roman_ci",
	240: "utf8mb4_persian_ci",
	241: "utf8mb4_esperanto_ci",
	242: "utf8mb4_hungarian_ci",
	243: "utf8mb4_sinhala_ci",
	244: "utf8mb4_german2_ci",
	245: "utf8mb4_croatian_ci",
	246: "utf8mb4_unicode_520_ci",
	247: "utf8mb4_vietnamese_ci",
	255: "utf8mb4_0900_ai_ci",
}

// CollationNames maps MySQL collation name to its ID
var CollationNames = map[string]uint8{
	"big5_chinese_ci":          1,
	"latin2_czech_cs":          2,
	"dec8_swedish_ci":          3,
	"cp850_general_ci":         4,
	"latin1_german1_ci":        5,
	"hp8_english_ci":           6,
	"koi8r_general_ci":         7,
	"latin1_swedish_ci":        8,
	"latin2_general_ci":        9,
	"swe7_swedish_ci":          10,
	"ascii_general_ci":         11,
	"ujis_japanese_ci":         12,
	"sjis_japanese_ci":         13,
	"cp1251_bulgarian_ci":      14,
	"latin1_danish_ci":         15,
	"hebrew_general_ci":        16,
	"tis620_thai_ci":           18,
	"euckr_korean_ci":          19,
	"latin7_estonian_cs":       20,
	"latin2_hungarian_ci":      21,
	"koi8u_general_ci":         22,
	"cp1251_ukrainian_ci":      23,
	"gb2312_chinese_ci":        24,
	"greek_general_ci":         25,
	"cp1250_general_ci":        26,
	"latin2_croatian_ci":       27,
	"gbk_chinese_ci":           28,
	"cp1257_lithuanian_ci":     29,
	"latin5_turkish_ci":        30,
	"latin1_german2_ci":        31,
	"armscii8_general_ci":      32,
	"utf8_general_ci":          33,
	"cp1250_czech_cs":          34,
	"ucs2_general_ci":          35,
	"cp866_general_ci":         36,
	"keybcs2_general_ci":       37,
	"macce_general_ci":         38,
	"macroman_general_ci":      39,
	"cp852_general_ci":         40,
	"latin7_general_ci":        41,
	"latin7_general_cs":        42,
	"macce_bin":                43,
	"cp1250_croatian_ci":       44,
	"utf8mb4_general_ci":       45,
	"utf8mb4_bin":              46,
	"latin1_bin":               47,
	"latin1_general_ci":        48,
	"latin1_general_cs":        49,
	"cp1251_bin":               50,
	"cp1251_general_ci":        51,
	"cp1251_general_cs":        52,
	"macroman_bin":             53,
	"utf16_general_ci":         54,
	"utf16_bin":                55,
	"utf16le_general_ci":       56,
	"cp1256_general_ci":        57,
	"cp1257_bin":               58,
	"cp1257_general_ci":        59,
	"utf32_general_ci":         60,
	"utf32_bin":                61,
	"utf16le_bin":              62,
	"binary":                   63,
	"armscii8_bin":             64,
	"ascii_bin":                65,
	"cp1250_bin":               66,
	"cp1256_bin":               67,
	"cp866_bin":                68,
	"dec8_bin":                 69,
	"greek_bin":                70,
	"hebrew_bin":               71,
	"hp8_bin":                  72,
	"keybcs2_bin":              73,
	"koi8r_bin":                74,
	"koi8u_bin":                75,
	"latin2_bin":               77,
	"latin5_bin":               78,
	"latin7_bin":               79,
	"cp850_bin":                80,
	"cp852_bin":                81,
	"swe7_bin":                 82,
	"utf8_bin":                 83,
	"big5_bin":                 84,
	"euckr_bin":                85,
	"gb2312_bin":               86,
	"gbk_bin":                  87,
	"sjis_bin":                 88,
	"tis620_bin":               89,
	"ucs2_bin":                 90,
	"ujis_bin":                 91,
	"geostd8_general_ci":       92,
	"geostd8_bin":              93,
	"latin1_spanish_ci":        94,
	"cp932_japanese_ci":        95,
	"cp932_bin":                96,
	"eucjpms_japanese_ci":      97,
	"eucjpms_bin":              98,
	"cp1250_polish_ci":         99,
	"utf16_unicode_ci":         101,
	"utf16_icelandic_ci":       102,
	"utf16_latvian_ci":         103,
	"utf16_romanian_ci":        104,
	"utf16_slovenian_ci":       105,
	"utf16_polish_ci":          106,
	"utf16_estonian_ci":        107,
	"utf16_spanish_ci":         108,
	"utf16_swedish_ci":         109,
	"utf16_turkish_ci":         110,
	"utf16_czech_ci":           111,
	"utf16_danish_ci":          112,
	"utf16_lithuanian_ci":      113,
	"utf16_slovak_ci":          114,
	"utf16_spanish2_ci":        115,
	"utf16_roman_ci":           116,
	"utf16_persian_ci":         117,
	"utf16_esperanto_ci":       118,
	"utf16_hungarian_ci":       119,
	"utf16_sinhala_ci":         120,
	"utf16_german2_ci":         121,
	"utf16_croatian_ci":        122,
	"utf16_unicode_520_ci":     123,
	"utf16_vietnamese_ci":      124,
	"ucs2_unicode_ci":          128,
	"ucs2_icelandic_ci":        129,
	"ucs2_latvian_ci":          130,
	"ucs2_romanian_ci":         131,
	"ucs2_slovenian_ci":        132,
	"ucs2_polish_ci":           133,
	"ucs2_estonian_ci":         134,
	"ucs2_spanish_ci":          135,
	"ucs2_swedish_ci":          136,
	"ucs2_turkish_ci":          137,
	"ucs2_czech_ci":            138,
	"ucs2_danish_ci":           139,
	"ucs2_lithuanian_ci":       140,
	"ucs2_slovak_ci":           141,
	"ucs2_spanish2_ci":         142,
	"ucs2_roman_ci":            143,
	"ucs2_persian_ci":          144,
	"ucs2_esperanto_ci":        145,
	"ucs2_hungarian_ci":        146,
	"ucs2_sinhala_ci":          147,
	"ucs2_german2_ci":          148,
	"ucs2_croatian_ci":         149,
	"ucs2_unicode_520_ci":      150,
	"ucs2_vietnamese_ci":       151,
	"ucs2_general_mysql500_ci": 159,
	"utf32_unicode_ci":         160,
	"utf32_icelandic_ci":       161,
	"utf32_latvian_ci":         162,
	"utf32_romanian_ci":        163,
	"utf32_slovenian_ci":       164,
	"utf32_polish_ci":          165,
	"utf32_estonian_ci":        166,
	"utf32_spanish_ci":         167,
	"utf32_swedish_ci":         168,
	"utf32_turkish_ci":         169,
	"utf32_czech_ci":           170,
	"utf32_danish_ci":          171,
	"utf32_lithuanian_ci":      172,
	"utf32_slovak_ci":          173,
	"utf32_spanish2_ci":        174,
	"utf32_roman_ci":           175,
	"utf32_persian_ci":         176,
	"utf32_esperanto_ci":       177,
	"utf32_hungarian_ci":       178,
	"utf32_sinhala_ci":         179,
	"utf32_german2_ci":         180,
	"utf32_croatian_ci":        181,
	"utf32_unicode_520_ci":     182,
	"utf32_vietnamese_ci":      183,
	"utf8_unicode_ci":          192,
	"utf8_icelandic_ci":        193,
	"utf8_latvian_ci":          194,
	"utf8_romanian_ci":         195,
	"utf8_slovenian_ci":        196,
	"utf8_polish_ci":           197,
	"utf8_estonian_ci":         198,
	"utf8_spanish_ci":          199,
	"utf8_swedish_ci":          200,
	"utf8_turkish_ci":          201,
	"utf8_czech_ci":            202,
	"utf8_danish_ci":           203,
	"utf8_lithuanian_ci":       204,
	"utf8_slovak_ci":           205,
	"utf8_spanish2_ci":         206,
	"utf8_roman_ci":            207,
	"utf8_persian_ci":          208,
	"utf8_esperanto_ci":        209,
	"utf8_hungarian_ci":        210,
	"utf8_sinhala_ci":          211,
	"utf8_german2_ci":          212,
	"utf8_croatian_ci":         213,
	"utf8_unicode_520_ci":      214,
	"utf8_vietnamese_ci":       215,
	"utf8_general_mysql500_ci": 223,
	"utf8mb4_unicode_ci":       224,
	"utf8mb4_icelandic_ci":     225,
	"utf8mb4_latvian_ci":       226,
	"utf8mb4_romanian_ci":      227,
	"utf8mb4_slovenian_ci":     228,
	"utf8mb4_polish_ci":        229,
	"utf8mb4_estonian_ci":      230,
	"utf8mb4_spanish_ci":       231,
	"utf8mb4_swedish_ci":       232,
	"utf8mb4_turkish_ci":       233,
	"utf8mb4_czech_ci":         234,
	"utf8mb4_danish_ci":        235,
	"utf8mb4_lithuanian_ci":    236,
	"utf8mb4_slovak_ci":        237,
	"utf8mb4_spanish2_ci":      238,
	"utf8mb4_roman_ci":         239,
	"utf8mb4_persian_ci":       240,
	"utf8mb4_esperanto_ci":     241,
	"utf8mb4_hungarian_ci":     242,
	"utf8mb4_sinhala_ci":       243,
	"utf8mb4_german2_ci":       244,
	"utf8mb4_croatian_ci":      245,
	"utf8mb4_unicode_520_ci":   246,
	"utf8mb4_vietnamese_ci":    247,
	"utf8mb4_0900_ai_ci":       255,
}

// MySQL collation information.
const (
	UTF8Charset    = "utf8"
	UTF8MB4Charset = "utf8mb4"
	DefaultCharset = UTF8MB4Charset
	// DefaultCollationID is utf8mb4_bin(46)
	DefaultCollationID        = 46
	Latin1DefaultCollationID  = 47
	ASCIIDefaultCollationID   = 65
	UTF8DefaultCollationID    = 83
	UTF8MB4DefaultCollationID = 46
	BinaryDefaultCollationID  = 63
	UTF8DefaultCollation      = "utf8_bin"
	UTF8MB4DefaultCollation   = "utf8mb4_bin"
	DefaultCollationName      = UTF8MB4DefaultCollation

	// MaxBytesOfCharacter, is the max bytes length of a character,
	// refer to RFC3629, in UTF-8, characters from the U+0000..U+10FFFF range
	// (the UTF-16 accessible range) are encoded using sequences of 1 to 4 octets.
	MaxBytesOfCharacter = 4
)

// IsUTF8Charset checks if charset is utf8 or utf8mb4
func IsUTF8Charset(charset string) bool {
	return charset == UTF8Charset || charset == UTF8MB4Charset
}

// RangeGraph defines valid unicode characters to use in column names. It strictly follows MySQL's definition.
// See #3994.
var RangeGraph = []*unicode.RangeTable{
	// _MY_PNT
	unicode.No,
	unicode.Mn,
	unicode.Me,
	unicode.Pc,
	unicode.Pd,
	unicode.Pd,
	unicode.Ps,
	unicode.Pe,
	unicode.Pi,
	unicode.Pf,
	unicode.Po,
	unicode.Sm,
	unicode.Sc,
	unicode.Sk,
	unicode.So,
	// _MY_U
	unicode.Lu,
	unicode.Lt,
	unicode.Nl,
	// _MY_L
	unicode.Ll,
	unicode.Lm,
	unicode.Lo,
	unicode.Nl,
	unicode.Mn,
	unicode.Mc,
	unicode.Me,
	// _MY_NMR
	unicode.Nd,
	unicode.Nl,
	unicode.No,
}