package main

import (
	"fmt"
	"os"
	"path/filepath"
	"sort"
	"strings"
	"text/template"

	"github.com/vattle/sqlboiler/bdb"
	"github.com/vattle/sqlboiler/strmangle"
)

// templateData for sqlboiler templates
type templateData struct {
	Tables          []bdb.Table
	Table           bdb.Table
	DriverName      string
	UseLastInsertID bool
	PkgName         string

	StringFuncs map[string]func(string) string
}

type templateList struct {
	*template.Template
}

type templateNameList []string

func (t templateNameList) Len() int {
	return len(t)
}

func (t templateNameList) Swap(k, j int) {
	t[k], t[j] = t[j], t[k]
}

func (t templateNameList) Less(k, j int) bool {
	// Make sure "struct" goes to the front
	if t[k] == "struct.tpl" {
		return true
	}

	res := strings.Compare(t[k], t[j])
	if res <= 0 {
		return true
	}

	return false
}

// Templates returns the name of all the templates defined in the template list
func (t templateList) Templates() []string {
	tplList := t.Template.Templates()

	if len(tplList) == 0 {
		return nil
	}

	ret := make([]string, 0, len(tplList))
	for _, tpl := range tplList {
		if name := tpl.Name(); strings.HasSuffix(name, ".tpl") {
			ret = append(ret, name)
		}
	}

	sort.Sort(templateNameList(ret))

	return ret
}

// loadTemplates loads all of the template files in the specified directory.
func loadTemplates(dir string) (*templateList, error) {
	wd, err := os.Getwd()
	if err != nil {
		return nil, err
	}

	pattern := filepath.Join(wd, dir, "*.tpl")
	tpl, err := template.New("").Funcs(templateFunctions).ParseGlob(pattern)

	if err != nil {
		return nil, err
	}

	return &templateList{Template: tpl}, err
}

// loadTemplate loads a single template file.
func loadTemplate(dir string, filename string) (*template.Template, error) {
	wd, err := os.Getwd()
	if err != nil {
		return nil, err
	}

	pattern := filepath.Join(wd, dir, filename)
	tpl, err := template.New("").Funcs(templateFunctions).ParseFiles(pattern)

	if err != nil {
		return nil, err
	}

	return tpl.Lookup(filename), err
}

// templateStringMappers are placed into the data to make it easy to use the
// stringMap function.
var templateStringMappers = map[string]func(string) string{
	// String ops
	"quoteWrap": func(a string) string { return fmt.Sprintf(`"%s"`, a) },

	// Casing
	"titleCase": strmangle.TitleCase,
	"camelCase": strmangle.CamelCase,
}

// templateFunctions is a map of all the functions that get passed into the
// templates. If you wish to pass a new function into your own template,
// add a function pointer here.
var templateFunctions = template.FuncMap{
	// String ops
	"quoteWrap": func(a string) string { return fmt.Sprintf(`"%s"`, a) },
	"id":        strmangle.Identifier,

	// Pluralization
	"singular": strmangle.Singular,
	"plural":   strmangle.Plural,

	// Casing
	"titleCase": strmangle.TitleCase,
	"camelCase": strmangle.CamelCase,

	// String Slice ops
	"join":              func(sep string, slice []string) string { return strings.Join(slice, sep) },
	"joinSlices":        strmangle.JoinSlices,
	"stringMap":         strmangle.StringMap,
	"prefixStringSlice": strmangle.PrefixStringSlice,

	// String Map ops
	"makeStringMap": strmangle.MakeStringMap,

	// Set operations
	"setInclude": strmangle.SetInclude,

	// Database related mangling
	"whereClause": strmangle.WhereClause,

	// Text helpers
	"textsFromForeignKey":           textsFromForeignKey,
	"textsFromOneToOneRelationship": textsFromOneToOneRelationship,
	"textsFromRelationship":         textsFromRelationship,

	// dbdrivers ops
	"filterColumnsByDefault": bdb.FilterColumnsByDefault,
	"sqlColDefinitions":      bdb.SQLColDefinitions,
	"columnNames":            bdb.ColumnNames,
	"columnDBTypes":          bdb.ColumnDBTypes,
	"getTable":               bdb.GetTable,
}