package pwgenerator

import (
	"encoding/xml"
	"time"
)

// pwHash is an explicit hash algorithm.
type pwHash uint8

// cryptoShuffler is used to shuffle a slice in a cryptographically sane way.
type cryptoShuffler struct{}

// Char is implemented as a rune.
type Char rune

// CharSet is a collection of characters (Char) but with additional methods (e.g. sort.Sort interface conformance).
type CharSet []Char

// GenOpts controls what kind of (and how many) password(s) should be generated.
type GenOpts struct {
	/*
		Some references below contain a reference to the character's hex ASCII.
		If you need the decimal/octal/etc. reference instead, you can cross-reference
		it via https://square-r00t.net/ascii.html.
	*/
	/*
		HumanOnly avoids visually-ambiguous characters if enabled, ensuring a more readable, visually-distinguishable,
		and accessible but MUCH smaller password character space (from about 220 characters to ), thus much less secure.

		TODO: Get feedback on this. I feel like I'm trimming out WAY too many chars.
	*/
	// HumanOnly        bool   `json:"do_human_readable" toml:"do_human_readable" yaml:"Human-Readable Only" xml:"doHumanReadable,attr"`
	// Alpha is true if letters (0x41 to 0x5a, 0x61 to 0x7a) should be included.
	Alpha bool `json:"do_alpha" toml:"Letters" yaml:"Letters" xml:"doAlpha,attr"`
	// Numeric is true if numbers (0x30 to 0x39) should be included.
	Numeric bool `json:"do_numeric" toml:"Numbers" yaml:"Numbers" xml:"doNumeric,attr"`
	// Symbols is true if non-alphanumeric characters (between 0x21 and 0x7e) should be included.
	Symbols bool `json:"do_symbols" toml:"Symbols" yaml:"Symbols" xml:"doSymbols,attr"`
	// ExtendedSymbols is true if non-alphanumeric characters in the "extended ASCII" set (0x80 to 0xff) should be included.
	ExtendedSymbols bool `json:"do_extended" toml:"ExtendedSymbols" yaml:"Extended Symbols" xml:"doExtendedSymbols,attr"`
	// CountUpper specifies how many uppercase letters (0x41 to 0x5a) should be specified at a minimum.
	CountUpper uint `json:"uppers" toml:"CountUpper" yaml:"Number of Uppercase Letters" xml:"numUppers,attr"`
	// CountLower specifies how many lowercase letters (0x61 to 0x7a) should be specified at a minimum.
	CountLower uint `json:"lowers" toml:"CountLower" yaml:"Number of Lowercase Letters" xml:"numLowers,attr"`
	// CountNumbers specifies how many numbers (0x30 to 0x39) should be specified at a minimum.
	CountNumbers uint `json:"numbers" toml:"CountNumber" yaml:"Number of Numeric Characters" xml:"numNumeric,attr"`
	// CountSymbols specifies how many symbols (0x21 to 0x7e) should be specified at a minimum.
	CountSymbols uint `json:"symbols" toml:"CountSymbol" yaml:"Number of Symbols" xml:"numSymbols,attr"`
	// CountExtended specifies how many extended symbols (0x80 to 0xff) should be specified at a minimum.
	CountExtended uint `json:"extended" toml:"CountExtended" yaml:"Number of Extended Symbols" xml:"numXSymbols,attr"`
	// DisabledChars includes characters that should NOT be included from the above selection options.
	DisabledChars CharSet `json:"disabled_chars,omitempty" toml:"DisabledCharSet,omitempty" yaml:"Disabled CharSet,omitempty" xml:"disabledChars,attr,omitempty"`
	// LengthMin specifies how long (in characters/bytes) each password should be at minimum. Use 0 for no minimum.
	LengthMin uint `json:"length_min" toml:"MinLength" yaml:"Minimum Length" xml:"minLen,attr"`
	/*
		LengthMax specifies the maximum length for each password. Set to 0 for no limit
		(the language has a hard limit of 18446744073709551615; this is limited to 256 for performance reasons).
	*/
	LengthMax uint `json:"length_max" toml:"MaxLength" yaml:"Maximum Length" xml:"maxLen,attr"`
	// Count specifies how many passwords to generate. If 0, the default is 1.
	Count uint `json:"count" toml:"Count" yaml:"Number of Passwords" xml:"genCount,attr"`
	// explicitCharset is the collection of acceptable characters as explicitly defined by the caller, if any.
	explicitCharset CharSet
}

// PwCollection contains the full series of generated passwords.
type PwCollection struct {
	XMLName   xml.Name `json:"-" yaml:"-"`
	Passwords []*PwDef `json:"password_defs" yaml:"Password Definitions" xml:"passwordDefs"`
}

// PwDef contains a generated password and related metadata.
type PwDef struct {
	XMLName   xml.Name    `json:"-" yaml:"-"`
	Password  string      `json:"password" yaml:"Password" xml:"password,attr"`
	Generated time.Time   `json:"generated" yaml:"Generated" xml:"generated,attr"`
	Hashes    []PwHashDef `json:"hashes,omitempty" yaml:"Hashes,omitempty" xml:"hashes,omitempty"`
	// Hashes []PwHashDef `json:"hashes" yaml:"Hashes" xml:"hashes"`
}

// PwHashDef defines a hash for a PwDef (once we implement it). Might want to move it to the pwhash subpackage.
type PwHashDef struct {
	XMLName    xml.Name `json:"-" yaml:"-"`
	HashType   string   `json:"hash_algo" yaml:"Hash Algorithm" xml:"hashAlgo,attr"`
	HashString string   `json:"hash" yaml:"Hash" xml:",chardata"`
}

// selectFilter is used to include specified number of characters.
type selectFilter struct {
	upperCounter    uint
	lowerCounter    uint
	numberCounter   uint
	symbolCounter   uint
	extendedCounter uint
}